Class Cv2

OpenCV Functions of C++ I/F (cv::xxx)

Inheritance

System.Object

Cv2

Inherited Members

System.Object.Equals(System.Object)

System.Object.Equals(System.Object, System.Object)

System.Object.GetHashCode()

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ReferenceEquals(System.Object, System.Object)

System.Object.ToString()

Namespace: OpenCvSharp

Assembly: OpenCvSharp.dll

Syntax

public static class Cv2

Fields

FILLED

Declaration

public const int FILLED = -1

Field Value

Type	Description
System.Int32

LOG2

Declaration

public const double LOG2 = 0.69314718055994529

Field Value

Type	Description
System.Double

PI

The ratio of a circle's circumference to its diameter

Declaration

public const double PI = 3.1415926535897931

Field Value

Type	Description
System.Double

Methods

Abs(Mat)

Computes absolute value of each matrix element

Declaration

public static MatExpr Abs(Mat src)

Parameters

Type	Name	Description
Mat	src	matrix

Returns

Type	Description
MatExpr

Abs(MatExpr)

Computes absolute value of each matrix element

Declaration

public static MatExpr Abs(MatExpr src)

Parameters

Type	Name	Description
MatExpr	src	matrix expression

Returns

Type	Description
MatExpr

Absdiff(InputArray, InputArray, OutputArray)

Calculates the per-element absolute difference between two arrays or between an array and a scalar.

Declaration

public static void Absdiff(InputArray src1, InputArray src2, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src1	first input array or a scalar.
InputArray	src2	second input array or a scalar.
OutputArray	dst	output array that has the same size and type as input arrays.

Accumulate(InputArray, InputOutputArray, InputArray)

Adds an image to the accumulator.

Declaration

public static void Accumulate(InputArray src, InputOutputArray dst, InputArray mask)

Parameters

Type	Name	Description
InputArray	src	Input image as 1- or 3-channel, 8-bit or 32-bit floating point.
InputOutputArray	dst	Accumulator image with the same number of channels as input image, 32-bit or 64-bit floating-point.
InputArray	mask	Optional operation mask.

AccumulateProduct(InputArray, InputArray, InputOutputArray, InputArray)

Adds the per-element product of two input images to the accumulator.

Declaration

public static void AccumulateProduct(InputArray src1, InputArray src2, InputOutputArray dst, InputArray mask)

Parameters

Type	Name	Description
InputArray	src1	First input image, 1- or 3-channel, 8-bit or 32-bit floating point.
InputArray	src2	Second input image of the same type and the same size as src1
InputOutputArray	dst	Accumulator with the same number of channels as input images, 32-bit or 64-bit floating-point.
InputArray	mask	Optional operation mask.

AccumulateSquare(InputArray, InputOutputArray, InputArray)

Adds the square of a source image to the accumulator.

Declaration

public static void AccumulateSquare(InputArray src, InputOutputArray dst, InputArray mask)

Parameters

Type	Name	Description
InputArray	src	Input image as 1- or 3-channel, 8-bit or 32-bit floating point.
InputOutputArray	dst	Accumulator image with the same number of channels as input image, 32-bit or 64-bit floating-point.
InputArray	mask	Optional operation mask.

AccumulateWeighted(InputArray, InputOutputArray, Double, InputArray)

Updates a running average.

Declaration

public static void AccumulateWeighted(InputArray src, InputOutputArray dst, double alpha, InputArray mask)

Parameters

Type	Name	Description
InputArray	src	Input image as 1- or 3-channel, 8-bit or 32-bit floating point.
InputOutputArray	dst	Accumulator image with the same number of channels as input image, 32-bit or 64-bit floating-point.
System.Double	alpha	Weight of the input image.
InputArray	mask	Optional operation mask.

AdaptiveThreshold(InputArray, OutputArray, Double, AdaptiveThresholdTypes, ThresholdTypes, Int32, Double)

Applies an adaptive threshold to an array.

Declaration

public static void AdaptiveThreshold(InputArray src, OutputArray dst, double maxValue, AdaptiveThresholdTypes adaptiveMethod, ThresholdTypes thresholdType, int blockSize, double c)

Parameters

Type	Name	Description
InputArray	src	Source 8-bit single-channel image.
OutputArray	dst	Destination image of the same size and the same type as src .
System.Double	maxValue	Non-zero value assigned to the pixels for which the condition is satisfied. See the details below.
AdaptiveThresholdTypes	adaptiveMethod	Adaptive thresholding algorithm to use, ADAPTIVE_THRESH_MEAN_C or ADAPTIVE_THRESH_GAUSSIAN_C .
ThresholdTypes	thresholdType	Thresholding type that must be either THRESH_BINARY or THRESH_BINARY_INV .
System.Int32	blockSize	Size of a pixel neighborhood that is used to calculate a threshold value for the pixel: 3, 5, 7, and so on.
System.Double	c	Constant subtracted from the mean or weighted mean (see the details below). Normally, it is positive but may be zero or negative as well.

Add(InputArray, InputArray, OutputArray, InputArray, Int32)

Computes the per-element sum of two arrays or an array and a scalar.

Declaration

public static void Add(InputArray src1, InputArray src2, OutputArray dst, InputArray mask = null, int dtype = -1)

Parameters

Type	Name	Description
InputArray	src1	The first source array
InputArray	src2	The second source array. It must have the same size and same type as src1
OutputArray	dst	The destination array; it will have the same size and same type as src1
InputArray	mask	The optional operation mask, 8-bit single channel array; specifies elements of the destination array to be changed. [By default this is null]
System.Int32	dtype

AddWeighted(InputArray, Double, InputArray, Double, Double, OutputArray, Int32)

computes weighted sum of two arrays (dst = alphasrc1 + betasrc2 + gamma)

Declaration

public static void AddWeighted(InputArray src1, double alpha, InputArray src2, double beta, double gamma, OutputArray dst, int dtype = -1)

Parameters

Type	Name	Description
InputArray	src1
System.Double	alpha
InputArray	src2
System.Double	beta
System.Double	gamma
OutputArray	dst
System.Int32	dtype

AGAST(InputArray, Int32, Boolean, AgastFeatureDetector.DetectorType)

Detects corners using the AGAST algorithm

Declaration

public static KeyPoint[] AGAST(InputArray image, int threshold, bool nonmaxSuppression, AgastFeatureDetector.DetectorType type)

Parameters

Type	Name	Description
InputArray	image	grayscale image where keypoints (corners) are detected.
System.Int32	threshold	threshold on difference between intensity of the central pixel and pixels of a circle around this pixel.
System.Boolean	nonmaxSuppression	if true, non-maximum suppression is applied to detected corners (keypoints).
OpenCvSharp.AgastFeatureDetector.DetectorType	type	one of the four neighborhoods as defined in the paper

Returns

Type	Description
OpenCvSharp.KeyPoint[]	keypoints detected on the image.

AlignSize(Int32, Int32)

Aligns buffer size by the certain number of bytes This small inline function aligns a buffer size by the certian number of bytes by enlarging it.

Declaration

public static int AlignSize(int sz, int n)

Parameters

Type	Name	Description
System.Int32	sz
System.Int32	n

Returns

Type	Description
System.Int32

ApplyColorMap(InputArray, OutputArray, ColormapTypes)

Applies a GNU Octave/MATLAB equivalent colormap on a given image.

Declaration

public static void ApplyColorMap(InputArray src, OutputArray dst, ColormapTypes colormap)

Parameters

Type	Name	Description
InputArray	src	The source image, grayscale or colored of type CV_8UC1 or CV_8UC3.
OutputArray	dst	The result is the colormapped source image. Note: Mat::create is called on dst.
ColormapTypes	colormap	colormap The colormap to apply

ApplyColorMap(InputArray, OutputArray, InputArray)

Applies a user colormap on a given image.

Declaration

public static void ApplyColorMap(InputArray src, OutputArray dst, InputArray userColor)

Parameters

Type	Name	Description
InputArray	src	The source image, grayscale or colored of type CV_8UC1 or CV_8UC3.
OutputArray	dst	The result is the colormapped source image. Note: Mat::create is called on dst.
InputArray	userColor	The colormap to apply of type CV_8UC1 or CV_8UC3 and size 256

ApproxPolyDP(IEnumerable<Point>, Double, Boolean)

Approximates contour or a curve using Douglas-Peucker algorithm

Declaration

public static Point[] ApproxPolyDP(IEnumerable<Point> curve, double epsilon, bool closed)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	curve	The polygon or curve to approximate.
System.Double	epsilon	Specifies the approximation accuracy. This is the maximum distance between the original curve and its approximation.
System.Boolean	closed	The result of the approximation; The type should match the type of the input curve

Returns

Type	Description
OpenCvSharp.Point[]	The result of the approximation; The type should match the type of the input curve

ApproxPolyDP(IEnumerable<Point2f>, Double, Boolean)

Approximates contour or a curve using Douglas-Peucker algorithm

Declaration

public static Point2f[] ApproxPolyDP(IEnumerable<Point2f> curve, double epsilon, bool closed)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	curve	The polygon or curve to approximate.
System.Double	epsilon	Specifies the approximation accuracy. This is the maximum distance between the original curve and its approximation.
System.Boolean	closed	If true, the approximated curve is closed (i.e. its first and last vertices are connected), otherwise it’s not

Returns

Type	Description
OpenCvSharp.Point2f[]	The result of the approximation; The type should match the type of the input curve

ApproxPolyDP(InputArray, OutputArray, Double, Boolean)

Approximates contour or a curve using Douglas-Peucker algorithm

Declaration

public static void ApproxPolyDP(InputArray curve, OutputArray approxCurve, double epsilon, bool closed)

Parameters

Type	Name	Description
InputArray	curve	The polygon or curve to approximate. Must be 1 x N or N x 1 matrix of type CV_32SC2 or CV_32FC2.
OutputArray	approxCurve	The result of the approximation; The type should match the type of the input curve
System.Double	epsilon	Specifies the approximation accuracy. This is the maximum distance between the original curve and its approximation.
System.Boolean	closed	The result of the approximation; The type should match the type of the input curve

ArcLength(IEnumerable<Point>, Boolean)

Calculates a contour perimeter or a curve length.

Declaration

public static double ArcLength(IEnumerable<Point> curve, bool closed)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	curve	The input vector of 2D points.
System.Boolean	closed	Indicates, whether the curve is closed or not.

Returns

Type	Description
System.Double

ArcLength(IEnumerable<Point2f>, Boolean)

Calculates a contour perimeter or a curve length.

Declaration

public static double ArcLength(IEnumerable<Point2f> curve, bool closed)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	curve	The input vector of 2D points.
System.Boolean	closed	Indicates, whether the curve is closed or not.

Returns

Type	Description
System.Double

ArcLength(InputArray, Boolean)

Calculates a contour perimeter or a curve length.

Declaration

public static double ArcLength(InputArray curve, bool closed)

Parameters

Type	Name	Description
InputArray	curve	The input vector of 2D points, represented by CV_32SC2 or CV_32FC2 matrix.
System.Boolean	closed	Indicates, whether the curve is closed or not.

Returns

Type	Description
System.Double

ArrowedLine(InputOutputArray, Point, Point, Scalar, Int32, LineTypes, Int32, Double)

Draws a arrow segment pointing from the first point to the second one. The function arrowedLine draws an arrow between pt1 and pt2 points in the image. See also cv::line.

Declaration

public static void ArrowedLine(InputOutputArray img, Point pt1, Point pt2, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0, double tipLength = 0.1)

Parameters

Type	Name	Description
InputOutputArray	img	Image.
OpenCvSharp.Point	pt1	The point the arrow starts from.
OpenCvSharp.Point	pt2	The point the arrow points to.
OpenCvSharp.Scalar	color	Line color.
System.Int32	thickness	Line thickness.
LineTypes	lineType	Type of the line, see cv::LineTypes
System.Int32	shift	Number of fractional bits in the point coordinates.
System.Double	tipLength	The length of the arrow tip in relation to the arrow length

BatchDistance(InputArray, InputArray, OutputArray, Int32, OutputArray, NormTypes, Int32, InputArray, Int32, Boolean)

naive nearest neighbor finder

Declaration

public static void BatchDistance(InputArray src1, InputArray src2, OutputArray dist, int dtype, OutputArray nidx, NormTypes normType = NormTypes.L2, int k = 0, InputArray mask = null, int update = 0, bool crosscheck = false)

Parameters

Type	Name	Description
InputArray	src1
InputArray	src2
OutputArray	dist
System.Int32	dtype
OutputArray	nidx
NormTypes	normType
System.Int32	k
InputArray	mask
System.Int32	update
System.Boolean	crosscheck

BilateralFilter(InputArray, OutputArray, Int32, Double, Double, BorderTypes)

Applies bilateral filter to the image

Declaration

public static void BilateralFilter(InputArray src, OutputArray dst, int d, double sigmaColor, double sigmaSpace, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	The source 8-bit or floating-point, 1-channel or 3-channel image
OutputArray	dst	The destination image; will have the same size and the same type as src
System.Int32	d	The diameter of each pixel neighborhood, that is used during filtering. If it is non-positive, it's computed from sigmaSpace
System.Double	sigmaColor	Filter sigma in the color space. Larger value of the parameter means that farther colors within the pixel neighborhood will be mixed together, resulting in larger areas of semi-equal color
System.Double	sigmaSpace	Filter sigma in the coordinate space. Larger value of the parameter means that farther pixels will influence each other (as long as their colors are close enough; see sigmaColor). Then d>0 , it specifies the neighborhood size regardless of sigmaSpace, otherwise d is proportional to sigmaSpace
BorderTypes	borderType

BitwiseAnd(InputArray, InputArray, OutputArray, InputArray)

computes bitwise conjunction of the two arrays (dst = src1 & src2)

Declaration

public static void BitwiseAnd(InputArray src1, InputArray src2, OutputArray dst, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src1	first input array or a scalar.
InputArray	src2	second input array or a scalar.
OutputArray	dst	output array that has the same size and type as the input
InputArray	mask	optional operation mask, 8-bit single channel array, that specifies elements of the output array to be changed.

BitwiseNot(InputArray, OutputArray, InputArray)

inverts each bit of array (dst = ~src)

Declaration

public static void BitwiseNot(InputArray src, OutputArray dst, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	input array.
OutputArray	dst	output array that has the same size and type as the input
InputArray	mask	optional operation mask, 8-bit single channel array, that specifies elements of the output array to be changed.

BitwiseOr(InputArray, InputArray, OutputArray, InputArray)

computes bitwise disjunction of the two arrays (dst = src1 | src2)

Declaration

public static void BitwiseOr(InputArray src1, InputArray src2, OutputArray dst, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src1	first input array or a scalar.
InputArray	src2	second input array or a scalar.
OutputArray	dst	output array that has the same size and type as the input
InputArray	mask	optional operation mask, 8-bit single channel array, that specifies elements of the output array to be changed.

BitwiseXor(InputArray, InputArray, OutputArray, InputArray)

computes bitwise exclusive-or of the two arrays (dst = src1 ^ src2)

Declaration

public static void BitwiseXor(InputArray src1, InputArray src2, OutputArray dst, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src1	first input array or a scalar.
InputArray	src2	second input array or a scalar.
OutputArray	dst	output array that has the same size and type as the input
InputArray	mask	optional operation mask, 8-bit single channel array, that specifies elements of the output array to be changed.

BlendLinear(InputArray, InputArray, InputArray, InputArray, OutputArray)

Performs linear blending of two images: dst(i,j) = weights1(i,j)*src1(i,j) + weights2(i,j)*src2(i,j)

Declaration

public static void BlendLinear(InputArray src1, InputArray src2, InputArray weights1, InputArray weights2, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src1	It has a type of CV_8UC(n) or CV_32FC(n), where n is a positive integer.
InputArray	src2	It has the same type and size as src1.
InputArray	weights1	It has a type of CV_32FC1 and the same size with src1.
InputArray	weights2	It has a type of CV_32FC1 and the same size with src1.
OutputArray	dst	It is created if it does not have the same size and type with src1.

Blur(InputArray, OutputArray, Size, Nullable<Point>, BorderTypes)

Smoothes image using normalized box filter

Declaration

public static void Blur(InputArray src, OutputArray dst, Size ksize, Point? anchor = null, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image; will have the same size and the same type as src
OpenCvSharp.Size	ksize	The smoothing kernel size
System.Nullable<OpenCvSharp.Point>	anchor	The anchor point. The default value Point(-1,-1) means that the anchor is at the kernel center
BorderTypes	borderType	The border mode used to extrapolate pixels outside of the image

BorderInterpolate(Int32, Int32, BorderTypes)

Computes the source location of an extrapolated pixel.

Declaration

public static int BorderInterpolate(int p, int len, BorderTypes borderType)

Parameters

Type	Name	Description
System.Int32	p	0-based coordinate of the extrapolated pixel along one of the axes, likely <0 or >= len
System.Int32	len	Length of the array along the corresponding axis.
BorderTypes	borderType	Border type, one of the #BorderTypes, except for #BORDER_TRANSPARENT and BORDER_ISOLATED. When borderType==BORDER_CONSTANT, the function always returns -1, regardless

Returns

Type	Description
System.Int32

BoundingRect(IEnumerable<Point>)

Calculates the up-right bounding rectangle of a point set.

Declaration

public static Rect BoundingRect(IEnumerable<Point> curve)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	curve	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.

Returns

Type	Description
OpenCvSharp.Rect	Minimal up-right bounding rectangle for the specified point set.

BoundingRect(IEnumerable<Point2f>)

Calculates the up-right bounding rectangle of a point set.

Declaration

public static Rect BoundingRect(IEnumerable<Point2f> curve)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	curve	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.

Returns

Type	Description
OpenCvSharp.Rect	Minimal up-right bounding rectangle for the specified point set.

BoundingRect(InputArray)

Calculates the up-right bounding rectangle of a point set.

Declaration

public static Rect BoundingRect(InputArray curve)

Parameters

Type	Name	Description
InputArray	curve	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.

Returns

Type	Description
OpenCvSharp.Rect	Minimal up-right bounding rectangle for the specified point set.

BoxFilter(InputArray, OutputArray, MatType, Size, Nullable<Point>, Boolean, BorderTypes)

Smoothes image using box filter

Declaration

public static void BoxFilter(InputArray src, OutputArray dst, MatType ddepth, Size ksize, Point? anchor = null, bool normalize = true, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image; will have the same size and the same type as src
OpenCvSharp.MatType	ddepth
OpenCvSharp.Size	ksize	The smoothing kernel size
System.Nullable<OpenCvSharp.Point>	anchor	The anchor point. The default value Point(-1,-1) means that the anchor is at the kernel center
System.Boolean	normalize	Indicates, whether the kernel is normalized by its area or not
BorderTypes	borderType	The border mode used to extrapolate pixels outside of the image

BoxPoints(RotatedRect)

Finds the four vertices of a rotated rect. Useful to draw the rotated rectangle.

The function finds the four vertices of a rotated rectangle.This function is useful to draw the rectangle.In C++, instead of using this function, you can directly use RotatedRect::points method. Please visit the @ref tutorial_bounding_rotated_ellipses "tutorial on Creating Bounding rotated boxes and ellipses for contours" for more information.

Declaration

public static Point2f[] BoxPoints(RotatedRect box)

Parameters

Type	Name	Description
OpenCvSharp.RotatedRect	box	The input rotated rectangle. It may be the output of

Returns

Type	Description
OpenCvSharp.Point2f[]	The output array of four vertices of rectangles.

BoxPoints(RotatedRect, OutputArray)

Finds the four vertices of a rotated rect. Useful to draw the rotated rectangle.

The function finds the four vertices of a rotated rectangle.This function is useful to draw the rectangle.In C++, instead of using this function, you can directly use RotatedRect::points method. Please visit the @ref tutorial_bounding_rotated_ellipses "tutorial on Creating Bounding rotated boxes and ellipses for contours" for more information.

Declaration

public static void BoxPoints(RotatedRect box, OutputArray points)

Parameters

Type	Name	Description
OpenCvSharp.RotatedRect	box	The input rotated rectangle. It may be the output of
OutputArray	points	The output array of four vertices of rectangles.

BuildOpticalFlowPyramid(InputArray, out Mat[], Size, Int32, Boolean, BorderTypes, BorderTypes, Boolean)

Constructs a pyramid which can be used as input for calcOpticalFlowPyrLK

Declaration

public static int BuildOpticalFlowPyramid(InputArray img, out Mat[] pyramid, Size winSize, int maxLevel, bool withDerivatives = true, BorderTypes pyrBorder = BorderTypes.Reflect101, BorderTypes derivBorder = BorderTypes.Constant, bool tryReuseInputImage = true)

Parameters

Type	Name	Description
InputArray	img	8-bit input image.
Mat[]	pyramid	output pyramid.
OpenCvSharp.Size	winSize	window size of optical flow algorithm. Must be not less than winSize argument of calcOpticalFlowPyrLK(). It is needed to calculate required padding for pyramid levels.
System.Int32	maxLevel	0-based maximal pyramid level number.
System.Boolean	withDerivatives	set to precompute gradients for the every pyramid level. If pyramid is constructed without the gradients then calcOpticalFlowPyrLK() will calculate them internally.
BorderTypes	pyrBorder	the border mode for pyramid layers.
BorderTypes	derivBorder	the border mode for gradients.
System.Boolean	tryReuseInputImage	put ROI of input image into the pyramid if possible. You can pass false to force data copying.

Returns

Type	Description
System.Int32	number of levels in constructed pyramid. Can be less than maxLevel.

BuildOpticalFlowPyramid(InputArray, OutputArray, Size, Int32, Boolean, BorderTypes, BorderTypes, Boolean)

Constructs a pyramid which can be used as input for calcOpticalFlowPyrLK

Declaration

public static int BuildOpticalFlowPyramid(InputArray img, OutputArray pyramid, Size winSize, int maxLevel, bool withDerivatives = true, BorderTypes pyrBorder = BorderTypes.Reflect101, BorderTypes derivBorder = BorderTypes.Constant, bool tryReuseInputImage = true)

Parameters

Type	Name	Description
InputArray	img	8-bit input image.
OutputArray	pyramid	output pyramid.
OpenCvSharp.Size	winSize	window size of optical flow algorithm. Must be not less than winSize argument of calcOpticalFlowPyrLK(). It is needed to calculate required padding for pyramid levels.
System.Int32	maxLevel	0-based maximal pyramid level number.
System.Boolean	withDerivatives	set to precompute gradients for the every pyramid level. If pyramid is constructed without the gradients then calcOpticalFlowPyrLK() will calculate them internally.
BorderTypes	pyrBorder	the border mode for pyramid layers.
BorderTypes	derivBorder	the border mode for gradients.
System.Boolean	tryReuseInputImage	put ROI of input image into the pyramid if possible. You can pass false to force data copying.

Returns

Type	Description
System.Int32	number of levels in constructed pyramid. Can be less than maxLevel.

BuildPyramid(InputArray, VectorOfMat, Int32, BorderTypes)

Declaration

public static void BuildPyramid(InputArray src, VectorOfMat dst, int maxlevel, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src
VectorOfMat	dst
System.Int32	maxlevel
BorderTypes	borderType

CalcBackProject(Mat[], Int32[], InputArray, OutputArray, Rangef[], Boolean)

computes the joint dense histogram for a set of images.

Declaration

public static void CalcBackProject(Mat[] images, int[] channels, InputArray hist, OutputArray backProject, Rangef[] ranges, bool uniform = true)

Parameters

Type	Name	Description
Mat[]	images
System.Int32[]	channels
InputArray	hist
OutputArray	backProject
OpenCvSharp.Rangef[]	ranges
System.Boolean	uniform

CalcCovarMatrix(InputArray, OutputArray, InputOutputArray, CovarFlags, Nullable<MatType>)

computes covariation matrix of a set of samples

Declaration

public static void CalcCovarMatrix(InputArray samples, OutputArray covar, InputOutputArray mean, CovarFlags flags, MatType? ctype = null)

Parameters

Type	Name	Description
InputArray	samples	samples stored as rows/columns of a single matrix.
OutputArray	covar	output covariance matrix of the type ctype and square size.
InputOutputArray	mean	input or output (depending on the flags) array as the average value of the input vectors.
CovarFlags	flags	operation flags as a combination of CovarFlags
System.Nullable<OpenCvSharp.MatType>	ctype	type of the matrixl; it equals 'CV_64F' by default.

CalcCovarMatrix(Mat[], Mat, Mat, CovarFlags, Nullable<MatType>)

computes covariation matrix of a set of samples

Declaration

public static void CalcCovarMatrix(Mat[] samples, Mat covar, Mat mean, CovarFlags flags, MatType? ctype = null)

Parameters

Type	Name	Description
Mat[]	samples	samples stored as separate matrices
Mat	covar	output covariance matrix of the type ctype and square size.
Mat	mean	input or output (depending on the flags) array as the average value of the input vectors.
CovarFlags	flags	operation flags as a combination of CovarFlags
System.Nullable<OpenCvSharp.MatType>	ctype	type of the matrixl; it equals 'CV_64F' by default.

CalcHist(Mat[], Int32[], InputArray, OutputArray, Int32, Int32[], Rangef[], Boolean, Boolean)

computes the joint dense histogram for a set of images.

Declaration

public static void CalcHist(Mat[] images, int[] channels, InputArray mask, OutputArray hist, int dims, int[] histSize, Rangef[] ranges, bool uniform = true, bool accumulate = false)

Parameters

Type	Name	Description
Mat[]	images
System.Int32[]	channels
InputArray	mask
OutputArray	hist
System.Int32	dims
System.Int32[]	histSize
OpenCvSharp.Rangef[]	ranges
System.Boolean	uniform
System.Boolean	accumulate

CalcHist(Mat[], Int32[], InputArray, OutputArray, Int32, Int32[], Single[][], Boolean, Boolean)

computes the joint dense histogram for a set of images.

Declaration

public static void CalcHist(Mat[] images, int[] channels, InputArray mask, OutputArray hist, int dims, int[] histSize, float[][] ranges, bool uniform = true, bool accumulate = false)

Parameters

Type	Name	Description
Mat[]	images
System.Int32[]	channels
InputArray	mask
OutputArray	hist
System.Int32	dims
System.Int32[]	histSize
System.Single[][]	ranges
System.Boolean	uniform
System.Boolean	accumulate

CalcOpticalFlowFarneback(InputArray, InputArray, InputOutputArray, Double, Int32, Int32, Int32, Int32, Double, OpticalFlowFlags)

Computes a dense optical flow using the Gunnar Farneback's algorithm.

Declaration

public static void CalcOpticalFlowFarneback(InputArray prev, InputArray next, InputOutputArray flow, double pyrScale, int levels, int winsize, int iterations, int polyN, double polySigma, OpticalFlowFlags flags)

Parameters

Type	Name	Description
InputArray	prev	first 8-bit single-channel input image.
InputArray	next	second input image of the same size and the same type as prev.
InputOutputArray	flow	computed flow image that has the same size as prev and type CV_32FC2.
System.Double	pyrScale	parameter, specifying the image scale (<1) to build pyramids for each image; pyrScale=0.5 means a classical pyramid, where each next layer is twice smaller than the previous one.
System.Int32	levels	number of pyramid layers including the initial image; levels=1 means that no extra layers are created and only the original images are used.
System.Int32	winsize	averaging window size; larger values increase the algorithm robustness to image noise and give more chances for fast motion detection, but yield more blurred motion field.
System.Int32	iterations	number of iterations the algorithm does at each pyramid level.
System.Int32	polyN	size of the pixel neighborhood used to find polynomial expansion in each pixel; larger values mean that the image will be approximated with smoother surfaces, yielding more robust algorithm and more blurred motion field, typically poly_n =5 or 7.
System.Double	polySigma	standard deviation of the Gaussian that is used to smooth derivatives used as a basis for the polynomial expansion; for polyN=5, you can set polySigma=1.1, for polyN=7, a good value would be polySigma=1.5.
OpticalFlowFlags	flags	operation flags that can be a combination of OPTFLOW_USE_INITIAL_FLOW and/or OPTFLOW_FARNEBACK_GAUSSIAN

CalcOpticalFlowPyrLK(InputArray, InputArray, InputArray, InputOutputArray, OutputArray, OutputArray, Nullable<Size>, Int32, Nullable<TermCriteria>, OpticalFlowFlags, Double)

computes sparse optical flow using multi-scale Lucas-Kanade algorithm

Declaration

public static void CalcOpticalFlowPyrLK(InputArray prevImg, InputArray nextImg, InputArray prevPts, InputOutputArray nextPts, OutputArray status, OutputArray err, Size? winSize = null, int maxLevel = 3, TermCriteria? criteria = null, OpticalFlowFlags flags = OpticalFlowFlags.None, double minEigThreshold = 0.0001)

Parameters

Type	Name	Description
InputArray	prevImg
InputArray	nextImg
InputArray	prevPts
InputOutputArray	nextPts
OutputArray	status
OutputArray	err
System.Nullable<OpenCvSharp.Size>	winSize
System.Int32	maxLevel
System.Nullable<OpenCvSharp.TermCriteria>	criteria
OpticalFlowFlags	flags
System.Double	minEigThreshold

CalcOpticalFlowPyrLK(InputArray, InputArray, Point2f[], ref Point2f[], out Byte[], out Single[], Nullable<Size>, Int32, Nullable<TermCriteria>, OpticalFlowFlags, Double)

computes sparse optical flow using multi-scale Lucas-Kanade algorithm

Declaration

public static void CalcOpticalFlowPyrLK(InputArray prevImg, InputArray nextImg, Point2f[] prevPts, ref Point2f[] nextPts, out byte[] status, out float[] err, Size? winSize = null, int maxLevel = 3, TermCriteria? criteria = null, OpticalFlowFlags flags = OpticalFlowFlags.None, double minEigThreshold = 0.0001)

Parameters

Type	Name	Description
InputArray	prevImg
InputArray	nextImg
OpenCvSharp.Point2f[]	prevPts
OpenCvSharp.Point2f[]	nextPts
System.Byte[]	status
System.Single[]	err
System.Nullable<OpenCvSharp.Size>	winSize
System.Int32	maxLevel
System.Nullable<OpenCvSharp.TermCriteria>	criteria
OpticalFlowFlags	flags
System.Double	minEigThreshold

CalibrateCamera(IEnumerable<IEnumerable<Point3f>>, IEnumerable<IEnumerable<Point2f>>, Size, Double[,], Double[], out Vec3d[], out Vec3d[], CalibrationFlags, Nullable<TermCriteria>)

finds intrinsic and extrinsic camera parameters from several fews of a known calibration pattern.

Declaration

public static double CalibrateCamera(IEnumerable<IEnumerable<Point3f>> objectPoints, IEnumerable<IEnumerable<Point2f>> imagePoints, Size imageSize, double[, ] cameraMatrix, double[] distCoeffs, out Vec3d[] rvecs, out Vec3d[] tvecs, CalibrationFlags flags = CalibrationFlags.None, TermCriteria? criteria = null)

Parameters

Type	Name	Description
IEnumerable<IEnumerable<OpenCvSharp.Point3f>>	objectPoints	In the new interface it is a vector of vectors of calibration pattern points in the calibration pattern coordinate space. The outer vector contains as many elements as the number of the pattern views. If the same calibration pattern is shown in each view and it is fully visible, all the vectors will be the same. Although, it is possible to use partially occluded patterns, or even different patterns in different views. Then, the vectors will be different. The points are 3D, but since they are in a pattern coordinate system, then, if the rig is planar, it may make sense to put the model to a XY coordinate plane so that Z-coordinate of each input object point is 0. In the old interface all the vectors of object points from different views are concatenated together.
IEnumerable<IEnumerable<OpenCvSharp.Point2f>>	imagePoints	In the new interface it is a vector of vectors of the projections of calibration pattern points. imagePoints.Count() and objectPoints.Count() and imagePoints[i].Count() must be equal to objectPoints[i].Count() for each i.
OpenCvSharp.Size	imageSize	Size of the image used only to initialize the intrinsic camera matrix.
System.Double[,]	cameraMatrix	Output 3x3 floating-point camera matrix. If CV_CALIB_USE_INTRINSIC_GUESS and/or CV_CALIB_FIX_ASPECT_RATIO are specified, some or all of fx, fy, cx, cy must be initialized before calling the function.
System.Double[]	distCoeffs	Output vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements.
Vec3d[]	rvecs	Output vector of rotation vectors (see Rodrigues() ) estimated for each pattern view. That is, each k-th rotation vector together with the corresponding k-th translation vector (see the next output parameter description) brings the calibration pattern from the model coordinate space (in which object points are specified) to the world coordinate space, that is, a real position of the calibration pattern in the k-th pattern view (k=0.. M -1)
Vec3d[]	tvecs	Output vector of translation vectors estimated for each pattern view.
CalibrationFlags	flags	Different flags that may be zero or a combination of the CalibrationFlag values
System.Nullable<OpenCvSharp.TermCriteria>	criteria	Termination criteria for the iterative optimization algorithm.

Returns

Type	Description
System.Double

CalibrateCamera(IEnumerable<Mat>, IEnumerable<Mat>, Size, InputOutputArray, InputOutputArray, out Mat[], out Mat[], CalibrationFlags, Nullable<TermCriteria>)

finds intrinsic and extrinsic camera parameters from several fews of a known calibration pattern.

Declaration

public static double CalibrateCamera(IEnumerable<Mat> objectPoints, IEnumerable<Mat> imagePoints, Size imageSize, InputOutputArray cameraMatrix, InputOutputArray distCoeffs, out Mat[] rvecs, out Mat[] tvecs, CalibrationFlags flags = CalibrationFlags.None, TermCriteria? criteria = null)

Parameters

Type	Name	Description
IEnumerable<Mat>	objectPoints	In the new interface it is a vector of vectors of calibration pattern points in the calibration pattern coordinate space. The outer vector contains as many elements as the number of the pattern views. If the same calibration pattern is shown in each view and it is fully visible, all the vectors will be the same. Although, it is possible to use partially occluded patterns, or even different patterns in different views. Then, the vectors will be different. The points are 3D, but since they are in a pattern coordinate system, then, if the rig is planar, it may make sense to put the model to a XY coordinate plane so that Z-coordinate of each input object point is 0. In the old interface all the vectors of object points from different views are concatenated together.
IEnumerable<Mat>	imagePoints	In the new interface it is a vector of vectors of the projections of calibration pattern points. imagePoints.Count() and objectPoints.Count() and imagePoints[i].Count() must be equal to objectPoints[i].Count() for each i.
OpenCvSharp.Size	imageSize	Size of the image used only to initialize the intrinsic camera matrix.
InputOutputArray	cameraMatrix	Output 3x3 floating-point camera matrix. If CV_CALIB_USE_INTRINSIC_GUESS and/or CV_CALIB_FIX_ASPECT_RATIO are specified, some or all of fx, fy, cx, cy must be initialized before calling the function.
InputOutputArray	distCoeffs	Output vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements.
Mat[]	rvecs	Output vector of rotation vectors (see Rodrigues() ) estimated for each pattern view. That is, each k-th rotation vector together with the corresponding k-th translation vector (see the next output parameter description) brings the calibration pattern from the model coordinate space (in which object points are specified) to the world coordinate space, that is, a real position of the calibration pattern in the k-th pattern view (k=0.. M -1)
Mat[]	tvecs	Output vector of translation vectors estimated for each pattern view.
CalibrationFlags	flags	Different flags that may be zero or a combination of the CalibrationFlag values
System.Nullable<OpenCvSharp.TermCriteria>	criteria	Termination criteria for the iterative optimization algorithm.

Returns

Type	Description
System.Double

CalibrateHandEye(IEnumerable<Mat>, IEnumerable<Mat>, IEnumerable<Mat>, IEnumerable<Mat>, OutputArray, OutputArray, HandEyeCalibrationMethod)

Computes Hand-Eye calibration.

The function performs the Hand-Eye calibration using various methods. One approach consists in estimating the rotation then the translation(separable solutions) and the following methods are implemented:

• R.Tsai, R.Lenz A New Technique for Fully Autonomous and Efficient 3D Robotics Hand/EyeCalibration \cite Tsai89
• F.Park, B.Martin Robot Sensor Calibration: Solving AX = XB on the Euclidean Group \cite Park94
• R.Horaud, F.Dornaika Hand-Eye Calibration \cite Horaud95

Another approach consists in estimating simultaneously the rotation and the translation(simultaneous solutions), with the following implemented method:

• N.Andreff, R.Horaud, B.Espiau On-line Hand-Eye Calibration \cite Andreff99
• K.Daniilidis Hand-Eye Calibration Using Dual Quaternions \cite Daniilidis98

Declaration

public static void CalibrateHandEye(IEnumerable<Mat> R_gripper2base, IEnumerable<Mat> t_gripper2base, IEnumerable<Mat> R_target2cam, IEnumerable<Mat> t_target2cam, OutputArray R_cam2gripper, OutputArray t_cam2gripper, HandEyeCalibrationMethod method = HandEyeCalibrationMethod.TSAI)

Parameters

Type	Name	Description
IEnumerable<Mat>	R_gripper2base	Rotation part extracted from the homogeneous matrix that transforms a pointexpressed in the gripper frame to the robot base frame that contains the rotation matrices for all the transformationsfrom gripper frame to robot base frame.
IEnumerable<Mat>	t_gripper2base	Translation part extracted from the homogeneous matrix that transforms a point expressed in the gripper frame to the robot base frame. This is a vector(vector&lt;Mat>) that contains the translation vectors for all the transformations from gripper frame to robot base frame.
IEnumerable<Mat>	R_target2cam	Rotation part extracted from the homogeneous matrix that transforms a point expressed in the target frame to the camera frame. This is a vector(vector&lt;Mat>) that contains the rotation matrices for all the transformations from calibration target frame to camera frame.
IEnumerable<Mat>	t_target2cam	Rotation part extracted from the homogeneous matrix that transforms a point expressed in the target frame to the camera frame. This is a vector(vector&lt;Mat>) that contains the translation vectors for all the transformations from calibration target frame to camera frame.
OutputArray	R_cam2gripper	Estimated rotation part extracted from the homogeneous matrix that transforms a point expressed in the camera frame to the gripper frame.
OutputArray	t_cam2gripper	Estimated translation part extracted from the homogeneous matrix that transforms a point expressed in the camera frame to the gripper frame.
HandEyeCalibrationMethod	method	One of the implemented Hand-Eye calibration method

CalibrateRobotWorldHandEye(IEnumerable<Mat>, IEnumerable<Mat>, IEnumerable<Mat>, IEnumerable<Mat>, OutputArray, OutputArray, OutputArray, OutputArray, RobotWorldHandEyeCalibrationMethod)

Computes Robot-World/Hand-Eye calibration. The function performs the Robot-World/Hand-Eye calibration using various methods. One approach consists in estimating the rotation then the translation(separable solutions):

• M.Shah, Solving the robot-world/hand-eye calibration problem using the kronecker product \cite Shah2013SolvingTR

Declaration

public static void CalibrateRobotWorldHandEye(IEnumerable<Mat> R_world2cam, IEnumerable<Mat> t_world2cam, IEnumerable<Mat> R_base2gripper, IEnumerable<Mat> t_base2gripper, OutputArray R_base2world, OutputArray t_base2world, OutputArray R_gripper2cam, OutputArray t_gripper2cam, RobotWorldHandEyeCalibrationMethod method = RobotWorldHandEyeCalibrationMethod.SHAH)

Parameters

Type	Name	Description
IEnumerable<Mat>	R_world2cam	[in] R_world2cam Rotation part extracted from the homogeneous matrix that transforms a point expressed in the world frame to the camera frame. This is a vector of Mat that contains the rotation, (3x3) rotation matrices or (3x1) rotation vectors,for all the transformations from world frame to the camera frame.
IEnumerable<Mat>	t_world2cam	[in] Translation part extracted from the homogeneous matrix that transforms a point expressed in the world frame to the camera frame. This is a vector (vector&lt;Mat>) that contains the (3x1) translation vectors for all the transformations from world frame to the camera frame.
IEnumerable<Mat>	R_base2gripper	[in] Rotation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the gripper frame. This is a vector (vector&lt;Mat>) that contains the rotation, (3x3) rotation matrices or (3x1) rotation vectors, for all the transformations from robot base frame to the gripper frame.
IEnumerable<Mat>	t_base2gripper	[in] Rotation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the gripper frame. This is a vector (vector&lt;Mat>) that contains the (3x1) translation vectors for all the transformations from robot base frame to the gripper frame.
OutputArray	R_base2world	[out] R_base2world Estimated (3x3) rotation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the world frame.
OutputArray	t_base2world	[out] t_base2world Estimated (3x1) translation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the world frame.
OutputArray	R_gripper2cam	[out] R_gripper2cam Estimated (3x3) rotation part extracted from the homogeneous matrix that transforms a point expressed in the gripper frame to the camera frame.
OutputArray	t_gripper2cam	[out] Estimated (3x1) translation part extracted from the homogeneous matrix that transforms a pointexpressed in the gripper frame to the camera frame.
RobotWorldHandEyeCalibrationMethod	method	One of the implemented Robot-World/Hand-Eye calibration method

CalibrateRobotWorldHandEye(IEnumerable<Mat>, IEnumerable<Mat>, IEnumerable<Mat>, IEnumerable<Mat>, out Double[,], out Double[], out Double[,], out Double[], RobotWorldHandEyeCalibrationMethod)

omputes Robot-World/Hand-Eye calibration. The function performs the Robot-World/Hand-Eye calibration using various methods. One approach consists in estimating the rotation then the translation(separable solutions):

• M.Shah, Solving the robot-world/hand-eye calibration problem using the kronecker product \cite Shah2013SolvingTR

Declaration

public static void CalibrateRobotWorldHandEye(IEnumerable<Mat> R_world2cam, IEnumerable<Mat> t_world2cam, IEnumerable<Mat> R_base2gripper, IEnumerable<Mat> t_base2gripper, out double[, ] R_base2world, out double[] t_base2world, out double[, ] R_gripper2cam, out double[] t_gripper2cam, RobotWorldHandEyeCalibrationMethod method = RobotWorldHandEyeCalibrationMethod.SHAH)

Parameters

Type	Name	Description
IEnumerable<Mat>	R_world2cam	[in] R_world2cam Rotation part extracted from the homogeneous matrix that transforms a point expressed in the world frame to the camera frame. This is a vector of Mat that contains the rotation, (3x3) rotation matrices or (3x1) rotation vectors,for all the transformations from world frame to the camera frame.
IEnumerable<Mat>	t_world2cam	[in] Translation part extracted from the homogeneous matrix that transforms a point expressed in the world frame to the camera frame. This is a vector (vector&lt;Mat>) that contains the (3x1) translation vectors for all the transformations from world frame to the camera frame.
IEnumerable<Mat>	R_base2gripper	[in] Rotation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the gripper frame. This is a vector (vector&lt;Mat>) that contains the rotation, (3x3) rotation matrices or (3x1) rotation vectors, for all the transformations from robot base frame to the gripper frame.
IEnumerable<Mat>	t_base2gripper	[in] Rotation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the gripper frame. This is a vector (vector&lt;Mat>) that contains the (3x1) translation vectors for all the transformations from robot base frame to the gripper frame.
System.Double[,]	R_base2world	[out] R_base2world Estimated (3x3) rotation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the world frame.
System.Double[]	t_base2world	[out] t_base2world Estimated (3x1) translation part extracted from the homogeneous matrix that transforms a point expressed in the robot base frame to the world frame.
System.Double[,]	R_gripper2cam	[out] R_gripper2cam Estimated (3x3) rotation part extracted from the homogeneous matrix that transforms a point expressed in the gripper frame to the camera frame.
System.Double[]	t_gripper2cam	[out] Estimated (3x1) translation part extracted from the homogeneous matrix that transforms a pointexpressed in the gripper frame to the camera frame.
RobotWorldHandEyeCalibrationMethod	method	One of the implemented Robot-World/Hand-Eye calibration method

CalibrationMatrixValues(InputArray, Size, Double, Double, out Double, out Double, out Double, out Point2d, out Double)

computes several useful camera characteristics from the camera matrix, camera frame resolution and the physical sensor size.

Declaration

public static void CalibrationMatrixValues(InputArray cameraMatrix, Size imageSize, double apertureWidth, double apertureHeight, out double fovx, out double fovy, out double focalLength, out Point2d principalPoint, out double aspectRatio)

Parameters

Type	Name	Description
InputArray	cameraMatrix	Input camera matrix that can be estimated by calibrateCamera() or stereoCalibrate() .
OpenCvSharp.Size	imageSize	Input image size in pixels.
System.Double	apertureWidth	Physical width of the sensor.
System.Double	apertureHeight	Physical height of the sensor.
System.Double	fovx	Output field of view in degrees along the horizontal sensor axis.
System.Double	fovy	Output field of view in degrees along the vertical sensor axis.
System.Double	focalLength	Focal length of the lens in mm.
OpenCvSharp.Point2d	principalPoint	Principal point in pixels.
System.Double	aspectRatio	fy / fx

CalibrationMatrixValues(Double[,], Size, Double, Double, out Double, out Double, out Double, out Point2d, out Double)

computes several useful camera characteristics from the camera matrix, camera frame resolution and the physical sensor size.

Declaration

public static void CalibrationMatrixValues(double[, ] cameraMatrix, Size imageSize, double apertureWidth, double apertureHeight, out double fovx, out double fovy, out double focalLength, out Point2d principalPoint, out double aspectRatio)

Parameters

Type	Name	Description
System.Double[,]	cameraMatrix	Input camera matrix that can be estimated by calibrateCamera() or stereoCalibrate() .
OpenCvSharp.Size	imageSize	Input image size in pixels.
System.Double	apertureWidth	Physical width of the sensor.
System.Double	apertureHeight	Physical height of the sensor.
System.Double	fovx	Output field of view in degrees along the horizontal sensor axis.
System.Double	fovy	Output field of view in degrees along the vertical sensor axis.
System.Double	focalLength	Focal length of the lens in mm.
OpenCvSharp.Point2d	principalPoint	Principal point in pixels.
System.Double	aspectRatio	fy / fx

CamShift(InputArray, ref Rect, TermCriteria)

Finds an object center, size, and orientation.

Declaration

public static RotatedRect CamShift(InputArray probImage, ref Rect window, TermCriteria criteria)

Parameters

Type	Name	Description
InputArray	probImage	Back projection of the object histogram.
OpenCvSharp.Rect	window	Initial search window.
OpenCvSharp.TermCriteria	criteria	Stop criteria for the underlying MeanShift() .

Returns

Type	Description
OpenCvSharp.RotatedRect

Canny(InputArray, InputArray, OutputArray, Double, Double, Boolean)

Finds edges in an image using the Canny algorithm with custom image gradient.

Declaration

public static void Canny(InputArray dx, InputArray dy, OutputArray edges, double threshold1, double threshold2, bool L2gradient = false)

Parameters

Type	Name	Description
InputArray	dx	16-bit x derivative of input image (CV_16SC1 or CV_16SC3).
InputArray	dy	16-bit y derivative of input image (same type as dx).
OutputArray	edges	output edge map; single channels 8-bit image, which has the same size as image.
System.Double	threshold1	first threshold for the hysteresis procedure.
System.Double	threshold2	second threshold for the hysteresis procedure.
System.Boolean	L2gradient	Indicates, whether the more accurate L2 norm should be used to compute the image gradient magnitude (true), or a faster default L1 norm is enough (false). [By default this is false]

Canny(InputArray, OutputArray, Double, Double, Int32, Boolean)

Finds edges in an image using Canny algorithm.

Declaration

public static void Canny(InputArray src, OutputArray edges, double threshold1, double threshold2, int apertureSize = 3, bool L2gradient = false)

Parameters

Type	Name	Description
InputArray	src	Single-channel 8-bit input image
OutputArray	edges	The output edge map. It will have the same size and the same type as image
System.Double	threshold1	The first threshold for the hysteresis procedure
System.Double	threshold2	The second threshold for the hysteresis procedure
System.Int32	apertureSize	Aperture size for the Sobel operator [By default this is ApertureSize.Size3]
System.Boolean	L2gradient	Indicates, whether the more accurate L2 norm should be used to compute the image gradient magnitude (true), or a faster default L1 norm is enough (false). [By default this is false]

CartToPolar(InputArray, InputArray, OutputArray, OutputArray, Boolean)

Calculates the magnitude and angle of 2D vectors.

Declaration

public static void CartToPolar(InputArray x, InputArray y, OutputArray magnitude, OutputArray angle, bool angleInDegrees = false)

Parameters

Type	Name	Description
InputArray	x	array of x-coordinates; this must be a single-precision or double-precision floating-point array.
InputArray	y	array of y-coordinates, that must have the same size and same type as x.
OutputArray	magnitude	output array of magnitudes of the same size and type as x.
OutputArray	angle	output array of angles that has the same size and type as x; the angles are measured in radians(from 0 to 2*Pi) or in degrees(0 to 360 degrees).
System.Boolean	angleInDegrees	a flag, indicating whether the angles are measured in radians(which is by default), or in degrees.

CheckChessboard(InputArray, Size)

Checks whether the image contains chessboard of the specific size or not.

Declaration

public static bool CheckChessboard(InputArray img, Size size)

Parameters

Type	Name	Description
InputArray	img
OpenCvSharp.Size	size

Returns

Type	Description
System.Boolean

CheckHardwareSupport(CpuFeatures)

Returns true if the specified feature is supported by the host hardware. The function returns true if the host hardware supports the specified feature.When user calls setUseOptimized(false), the subsequent calls to checkHardwareSupport() will return false until setUseOptimized(true) is called.This way user can dynamically switch on and off the optimized code in OpenCV.

Declaration

public static bool CheckHardwareSupport(CpuFeatures feature)

Parameters

Type	Name	Description
CpuFeatures	feature	The feature of interest, one of cv::CpuFeatures

Returns

Type	Description
System.Boolean

CheckRange(InputArray, Boolean)

checks that each matrix element is within the specified range.

Declaration

public static bool CheckRange(InputArray src, bool quiet = true)

Parameters

Type	Name	Description
InputArray	src	The array to check
System.Boolean	quiet	The flag indicating whether the functions quietly return false when the array elements are out of range, or they throw an exception.

Returns

Type	Description
System.Boolean

CheckRange(InputArray, Boolean, out Point, Double, Double)

checks that each matrix element is within the specified range.

Declaration

public static bool CheckRange(InputArray src, bool quiet, out Point pos, double minVal = -1.7976931348623157E+308, double maxVal = 1.7976931348623157E+308)

Parameters

Type	Name	Description
InputArray	src	The array to check
System.Boolean	quiet	The flag indicating whether the functions quietly return false when the array elements are out of range, or they throw an exception.
OpenCvSharp.Point	pos	The optional output parameter, where the position of the first outlier is stored.
System.Double	minVal	The inclusive lower boundary of valid values range
System.Double	maxVal	The exclusive upper boundary of valid values range

Returns

Type	Description
System.Boolean

Circle(InputOutputArray, Point, Int32, Scalar, Int32, LineTypes, Int32)

Draws a circle

Declaration

public static void Circle(InputOutputArray img, Point center, int radius, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	Image where the circle is drawn.
OpenCvSharp.Point	center	Center of the circle.
System.Int32	radius	Radius of the circle.
OpenCvSharp.Scalar	color	Circle color.
System.Int32	thickness	Thickness of the circle outline if positive, otherwise indicates that a filled circle has to be drawn. [By default this is 1]
LineTypes	lineType	Type of the circle boundary. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the center coordinates and radius value. [By default this is 0]

Circle(InputOutputArray, Int32, Int32, Int32, Scalar, Int32, LineTypes, Int32)

Draws a circle

Declaration

public static void Circle(InputOutputArray img, int centerX, int centerY, int radius, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	Image where the circle is drawn.
System.Int32	centerX	X-coordinate of the center of the circle.
System.Int32	centerY	Y-coordinate of the center of the circle.
System.Int32	radius	Radius of the circle.
OpenCvSharp.Scalar	color	Circle color.
System.Int32	thickness	Thickness of the circle outline if positive, otherwise indicates that a filled circle has to be drawn. [By default this is 1]
LineTypes	lineType	Type of the circle boundary. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the center coordinates and radius value. [By default this is 0]

ClipLine(Rect, ref Point, ref Point)

Clips the line against the image rectangle

Declaration

public static bool ClipLine(Rect imgRect, ref Point pt1, ref Point pt2)

Parameters

Type	Name	Description
OpenCvSharp.Rect	imgRect	sThe image rectangle
OpenCvSharp.Point	pt1	The first line point
OpenCvSharp.Point	pt2	The second line point

Returns

Type	Description
System.Boolean

ClipLine(Size, ref Point, ref Point)

Clips the line against the image rectangle

Declaration

public static bool ClipLine(Size imgSize, ref Point pt1, ref Point pt2)

Parameters

Type	Name	Description
OpenCvSharp.Size	imgSize	The image size
OpenCvSharp.Point	pt1	The first line point
OpenCvSharp.Point	pt2	The second line point

Returns

Type	Description
System.Boolean

ColorChange(InputArray, InputArray, OutputArray, Single, Single, Single)

Given an original color image, two differently colored versions of this image can be mixed seamlessly. Multiplication factor is between 0.5 to 2.5.

Declaration

public static void ColorChange(InputArray src, InputArray mask, OutputArray dst, float redMul = 1F, float greenMul = 1F, float blueMul = 1F)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
InputArray	mask	Input 8-bit 1 or 3-channel image.
OutputArray	dst	Output image with the same size and type as src.
System.Single	redMul	R-channel multiply factor.
System.Single	greenMul	G-channel multiply factor.
System.Single	blueMul	B-channel multiply factor.

Compare(InputArray, InputArray, OutputArray, CmpType)

Performs the per-element comparison of two arrays or an array and scalar value.

Declaration

public static void Compare(InputArray src1, InputArray src2, OutputArray dst, CmpType cmpop)

Parameters

Type	Name	Description
InputArray	src1	first input array or a scalar; when it is an array, it must have a single channel.
InputArray	src2	second input array or a scalar; when it is an array, it must have a single channel.
OutputArray	dst	output array of type ref CV_8U that has the same size and the same number of channels as the input arrays.
CmpType	cmpop	a flag, that specifies correspondence between the arrays (cv::CmpTypes)

CompareHist(InputArray, InputArray, HistCompMethods)

compares two histograms stored in dense arrays

Declaration

public static double CompareHist(InputArray h1, InputArray h2, HistCompMethods method)

Parameters

Type	Name	Description
InputArray	h1	The first compared histogram
InputArray	h2	The second compared histogram of the same size as h1
HistCompMethods	method	The comparison method

Returns

Type	Description
System.Double

CompleteSymm(InputOutputArray, Boolean)

extends the symmetrical matrix from the lower half or from the upper half

Declaration

public static void CompleteSymm(InputOutputArray mtx, bool lowerToUpper = false)

Parameters

Type	Name	Description
InputOutputArray	mtx	Input-output floating-point square matrix
System.Boolean	lowerToUpper	If true, the lower half is copied to the upper half, otherwise the upper half is copied to the lower half

ComposeRT(InputArray, InputArray, InputArray, InputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray)

composes 2 [R|t] transformations together. Also computes the derivatives of the result w.r.t the arguments

Declaration

public static void ComposeRT(InputArray rvec1, InputArray tvec1, InputArray rvec2, InputArray tvec2, OutputArray rvec3, OutputArray tvec3, OutputArray dr3dr1 = null, OutputArray dr3dt1 = null, OutputArray dr3dr2 = null, OutputArray dr3dt2 = null, OutputArray dt3dr1 = null, OutputArray dt3dt1 = null, OutputArray dt3dr2 = null, OutputArray dt3dt2 = null)

Parameters

Type	Name	Description
InputArray	rvec1	First rotation vector.
InputArray	tvec1	First translation vector.
InputArray	rvec2	Second rotation vector.
InputArray	tvec2	Second translation vector.
OutputArray	rvec3	Output rotation vector of the superposition.
OutputArray	tvec3	Output translation vector of the superposition.
OutputArray	dr3dr1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
OutputArray	dr3dt1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
OutputArray	dr3dr2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
OutputArray	dr3dt2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
OutputArray	dt3dr1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
OutputArray	dt3dt1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
OutputArray	dt3dr2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
OutputArray	dt3dt2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.

ComposeRT(Double[], Double[], Double[], Double[], out Double[], out Double[])

composes 2 [R|t] transformations together. Also computes the derivatives of the result w.r.t the arguments

Declaration

public static void ComposeRT(double[] rvec1, double[] tvec1, double[] rvec2, double[] tvec2, out double[] rvec3, out double[] tvec3)

Parameters

Type	Name	Description
System.Double[]	rvec1	First rotation vector.
System.Double[]	tvec1	First translation vector.
System.Double[]	rvec2	Second rotation vector.
System.Double[]	tvec2	Second translation vector.
System.Double[]	rvec3	Output rotation vector of the superposition.
System.Double[]	tvec3	Output translation vector of the superposition.

ComposeRT(Double[], Double[], Double[], Double[], out Double[], out Double[], out Double[,], out Double[,], out Double[,], out Double[,], out Double[,], out Double[,], out Double[,], out Double[,])

composes 2 [R|t] transformations together. Also computes the derivatives of the result w.r.t the arguments

Declaration

public static void ComposeRT(double[] rvec1, double[] tvec1, double[] rvec2, double[] tvec2, out double[] rvec3, out double[] tvec3, out double[, ] dr3dr1, out double[, ] dr3dt1, out double[, ] dr3dr2, out double[, ] dr3dt2, out double[, ] dt3dr1, out double[, ] dt3dt1, out double[, ] dt3dr2, out double[, ] dt3dt2)

Parameters

Type	Name	Description
System.Double[]	rvec1	First rotation vector.
System.Double[]	tvec1	First translation vector.
System.Double[]	rvec2	Second rotation vector.
System.Double[]	tvec2	Second translation vector.
System.Double[]	rvec3	Output rotation vector of the superposition.
System.Double[]	tvec3	Output translation vector of the superposition.
System.Double[,]	dr3dr1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
System.Double[,]	dr3dt1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
System.Double[,]	dr3dr2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
System.Double[,]	dr3dt2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
System.Double[,]	dt3dr1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
System.Double[,]	dt3dt1	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
System.Double[,]	dt3dr2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.
System.Double[,]	dt3dt2	Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and tvec2, respectively.

ComputeCorrespondEpilines(IEnumerable<Point2d>, Int32, Double[,])

For points in an image of a stereo pair, computes the corresponding epilines in the other image.

Declaration

public static Point3f[] ComputeCorrespondEpilines(IEnumerable<Point2d> points, int whichImage, double[, ] F)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2d>	points	Input points. N \times 1 or 1 x N matrix of type CV_32FC2 or CV_64FC2.
System.Int32	whichImage	Index of the image (1 or 2) that contains the points .
System.Double[,]	F	Fundamental matrix that can be estimated using findFundamentalMat() or stereoRectify() .

Returns

Type	Description
OpenCvSharp.Point3f[]	Output vector of the epipolar lines corresponding to the points in the other image. Each line ax + by + c=0 is encoded by 3 numbers (a, b, c) .

ComputeCorrespondEpilines(IEnumerable<Point3d>, Int32, Double[,])

For points in an image of a stereo pair, computes the corresponding epilines in the other image.

Declaration

public static Point3f[] ComputeCorrespondEpilines(IEnumerable<Point3d> points, int whichImage, double[, ] F)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3d>	points	Input points. N \times 1 or 1 x N matrix of type CV_32FC2 or CV_64FC2.
System.Int32	whichImage	Index of the image (1 or 2) that contains the points .
System.Double[,]	F	Fundamental matrix that can be estimated using findFundamentalMat() or stereoRectify() .

Returns

Type	Description
OpenCvSharp.Point3f[]	Output vector of the epipolar lines corresponding to the points in the other image. Each line ax + by + c=0 is encoded by 3 numbers (a, b, c) .

ComputeCorrespondEpilines(InputArray, Int32, InputArray, OutputArray)

For points in an image of a stereo pair, computes the corresponding epilines in the other image.

Declaration

public static void ComputeCorrespondEpilines(InputArray points, int whichImage, InputArray F, OutputArray lines)

Parameters

Type	Name	Description
InputArray	points	Input points. N \times 1 or 1 x N matrix of type CV_32FC2 or CV_64FC2.
System.Int32	whichImage	Index of the image (1 or 2) that contains the points .
InputArray	F	Fundamental matrix that can be estimated using findFundamentalMat() or stereoRectify() .
OutputArray	lines	Output vector of the epipolar lines corresponding to the points in the other image. Each line ax + by + c=0 is encoded by 3 numbers (a, b, c) .

ComputeECC(InputArray, InputArray, InputArray)

Computes the Enhanced Correlation Coefficient value between two images @cite EP08 .

Declaration

public static double ComputeECC(InputArray templateImage, InputArray inputImage, InputArray inputMask = null)

Parameters

Type	Name	Description
InputArray	templateImage	single-channel template image; CV_8U or CV_32F array.
InputArray	inputImage	single-channel input image to be warped to provide an image similar to templateImage, same type as templateImage.
InputArray	inputMask	An optional mask to indicate valid values of inputImage.

Returns

Type	Description
System.Double

ComputeRecallPrecisionCurve(DMatch[][], Byte[][])

Declaration

public static Point2f[] ComputeRecallPrecisionCurve(DMatch[][] matches1to2, byte[][] correctMatches1to2Mask)

Parameters

Type	Name	Description
OpenCvSharp.DMatch[][]	matches1to2
System.Byte[][]	correctMatches1to2Mask

Returns

Type	Description
OpenCvSharp.Point2f[]	recallPrecisionCurve

ConnectedComponents(InputArray, OutputArray, PixelConnectivity)

computes the connected components labeled image of boolean image. image with 4 or 8 way connectivity - returns N, the total number of labels [0, N-1] where 0 represents the background label. ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.

Declaration

public static int ConnectedComponents(InputArray image, OutputArray labels, PixelConnectivity connectivity = PixelConnectivity.Connectivity8)

Parameters

Type	Name	Description
InputArray	image	the image to be labeled
OutputArray	labels	destination labeled image
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively

Returns

Type	Description
System.Int32	The number of labels

ConnectedComponents(InputArray, OutputArray, PixelConnectivity, MatType)

computes the connected components labeled image of boolean image. image with 4 or 8 way connectivity - returns N, the total number of labels [0, N-1] where 0 represents the background label. ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.

Declaration

public static int ConnectedComponents(InputArray image, OutputArray labels, PixelConnectivity connectivity, MatType ltype)

Parameters

Type	Name	Description
InputArray	image	the image to be labeled
OutputArray	labels	destination labeled image
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively
OpenCvSharp.MatType	ltype	output image label type. Currently CV_32S and CV_16U are supported.

Returns

Type	Description
System.Int32	The number of labels

ConnectedComponents(InputArray, out Int32[,], PixelConnectivity)

computes the connected components labeled image of boolean image. image with 4 or 8 way connectivity - returns N, the total number of labels [0, N-1] where 0 represents the background label. ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.

Declaration

public static int ConnectedComponents(InputArray image, out int[, ] labels, PixelConnectivity connectivity)

Parameters

Type	Name	Description
InputArray	image	the image to be labeled
System.Int32[,]	labels	destination labeled rectangular array
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively

Returns

Type	Description
System.Int32	The number of labels

ConnectedComponentsEx(InputArray, PixelConnectivity, ConnectedComponentsAlgorithmsTypes)

computes the connected components labeled image of boolean image. image with 4 or 8 way connectivity - returns N, the total number of labels [0, N-1] where 0 represents the background label. ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.

Declaration

public static ConnectedComponents ConnectedComponentsEx(InputArray image, PixelConnectivity connectivity = PixelConnectivity.Connectivity8, ConnectedComponentsAlgorithmsTypes ccltype = ConnectedComponentsAlgorithmsTypes.Default)

Parameters

Type	Name	Description
InputArray	image	the image to be labeled
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively
ConnectedComponentsAlgorithmsTypes	ccltype

Returns

Type	Description
ConnectedComponents

ConnectedComponentsWithAlgorithm(InputArray, OutputArray, PixelConnectivity, MatType, ConnectedComponentsAlgorithmsTypes)

Computes the connected components labeled image of boolean image.

image with 4 or 8 way connectivity - returns N, the total number of labels[0, N - 1] where 0 represents the background label.ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.ccltype specifies the connected components labeling algorithm to use, currently Grana (BBDT) and Wu's (SAUF) algorithms are supported, see the #ConnectedComponentsAlgorithmsTypes for details.Note that SAUF algorithm forces a row major ordering of labels while BBDT does not. This function uses parallel version of both Grana and Wu's algorithms if at least one allowed parallel framework is enabled and if the rows of the image are at least twice the number returned by #getNumberOfCPUs.

Declaration

public static int ConnectedComponentsWithAlgorithm(InputArray image, OutputArray labels, PixelConnectivity connectivity, MatType ltype, ConnectedComponentsAlgorithmsTypes ccltype)

Parameters

Type	Name	Description
InputArray	image	the 8-bit single-channel image to be labeled
OutputArray	labels	destination labeled image
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively
OpenCvSharp.MatType	ltype	output image label type. Currently CV_32S and CV_16U are supported.
ConnectedComponentsAlgorithmsTypes	ccltype	connected components algorithm type.

Returns

Type	Description
System.Int32

ConnectedComponentsWithStats(InputArray, OutputArray, OutputArray, OutputArray, PixelConnectivity)

computes the connected components labeled image of boolean image. image with 4 or 8 way connectivity - returns N, the total number of labels [0, N-1] where 0 represents the background label. ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.

Declaration

public static int ConnectedComponentsWithStats(InputArray image, OutputArray labels, OutputArray stats, OutputArray centroids, PixelConnectivity connectivity = PixelConnectivity.Connectivity8)

Parameters

Type	Name	Description
InputArray	image	the image to be labeled
OutputArray	labels	destination labeled image
OutputArray	stats	statistics output for each label, including the background label, see below for available statistics. Statistics are accessed via stats(label, COLUMN) where COLUMN is one of cv::ConnectedComponentsTypes
OutputArray	centroids	floating point centroid (x,y) output for each label, including the background label
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively

Returns

Type	Description
System.Int32

ConnectedComponentsWithStats(InputArray, OutputArray, OutputArray, OutputArray, PixelConnectivity, MatType)

computes the connected components labeled image of boolean image. image with 4 or 8 way connectivity - returns N, the total number of labels [0, N-1] where 0 represents the background label. ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.

Declaration

public static int ConnectedComponentsWithStats(InputArray image, OutputArray labels, OutputArray stats, OutputArray centroids, PixelConnectivity connectivity, MatType ltype)

Parameters

Type	Name	Description
InputArray	image	the image to be labeled
OutputArray	labels	destination labeled image
OutputArray	stats	statistics output for each label, including the background label, see below for available statistics. Statistics are accessed via stats(label, COLUMN) where COLUMN is one of cv::ConnectedComponentsTypes
OutputArray	centroids	floating point centroid (x,y) output for each label, including the background label
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively
OpenCvSharp.MatType	ltype	output image label type. Currently CV_32S and CV_16U are supported.

Returns

Type	Description
System.Int32

ConnectedComponentsWithStatsWithAlgorithm(InputArray, OutputArray, OutputArray, OutputArray, PixelConnectivity, MatType, ConnectedComponentsAlgorithmsTypes)

computes the connected components labeled image of boolean image and also produces a statistics output for each label.

image with 4 or 8 way connectivity - returns N, the total number of labels[0, N - 1] where 0 represents the background label.ltype specifies the output label image type, an important consideration based on the total number of labels or alternatively the total number of pixels in the source image.ccltype specifies the connected components labeling algorithm to use, currently Grana's (BBDT) and Wu's (SAUF) algorithms are supported, see the #ConnectedComponentsAlgorithmsTypes for details.Note that SAUF algorithm forces a row major ordering of labels while BBDT does not. This function uses parallel version of both Grana and Wu's algorithms (statistics included) if at least one allowed parallel framework is enabled and if the rows of the image are at least twice the number returned by #getNumberOfCPUs.

Declaration

public static int ConnectedComponentsWithStatsWithAlgorithm(InputArray image, OutputArray labels, OutputArray stats, OutputArray centroids, PixelConnectivity connectivity, MatType ltype, ConnectedComponentsAlgorithmsTypes ccltype)

Parameters

Type	Name	Description
InputArray	image	the 8-bit single-channel image to be labeled
OutputArray	labels	destination labeled image
OutputArray	stats	statistics output for each label, including the background label, see below for available statistics.Statistics are accessed via stats(label, COLUMN) where COLUMN is one of #ConnectedComponentsTypes. The data type is CV_32S.
OutputArray	centroids	centroid output for each label, including the background label. Centroids are accessed via centroids(label, 0) for x and centroids(label, 1) for y.The data type CV_64F.
PixelConnectivity	connectivity	8 or 4 for 8-way or 4-way connectivity respectively
OpenCvSharp.MatType	ltype	output image label type. Currently CV_32S and CV_16U are supported.
ConnectedComponentsAlgorithmsTypes	ccltype	connected components algorithm type.

Returns

Type	Description
System.Int32

ContourArea(IEnumerable<Point>, Boolean)

Calculates the contour area

Declaration

public static double ContourArea(IEnumerable<Point> contour, bool oriented = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	contour	The contour vertices, represented by CV_32SC2 or CV_32FC2 matrix
System.Boolean	oriented

Returns

Type	Description
System.Double

ContourArea(IEnumerable<Point2f>, Boolean)

Calculates the contour area

Declaration

public static double ContourArea(IEnumerable<Point2f> contour, bool oriented = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	contour	The contour vertices, represented by CV_32SC2 or CV_32FC2 matrix
System.Boolean	oriented

Returns

Type	Description
System.Double

ContourArea(InputArray, Boolean)

Calculates the contour area

Declaration

public static double ContourArea(InputArray contour, bool oriented = false)

Parameters

Type	Name	Description
InputArray	contour	The contour vertices, represented by CV_32SC2 or CV_32FC2 matrix
System.Boolean	oriented

Returns

Type	Description
System.Double

ConvertFp16(InputArray, OutputArray)

Converts an array to half precision floating number.

This function converts FP32(single precision floating point) from/to FP16(half precision floating point). CV_16S format is used to represent FP16 data. There are two use modes(src -> dst) : CV_32F -> CV_16S and CV_16S -> CV_32F.The input array has to have type of CV_32F or CV_16S to represent the bit depth.If the input array is neither of them, the function will raise an error. The format of half precision floating point is defined in IEEE 754-2008.

Declaration

public static void ConvertFp16(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	input array.
OutputArray	dst	output array.

ConvertMaps(InputArray, InputArray, OutputArray, OutputArray, MatType, Boolean)

Converts image transformation maps from one representation to another.

Declaration

public static void ConvertMaps(InputArray map1, InputArray map2, OutputArray dstmap1, OutputArray dstmap2, MatType dstmap1Type, bool nnInterpolation = false)

Parameters

Type	Name	Description
InputArray	map1	The first input map of type CV_16SC2 , CV_32FC1 , or CV_32FC2 .
InputArray	map2	The second input map of type CV_16UC1 , CV_32FC1 , or none (empty matrix), respectively.
OutputArray	dstmap1	The first output map that has the type dstmap1type and the same size as src.
OutputArray	dstmap2	The second output map.
OpenCvSharp.MatType	dstmap1Type	Type of the first output map that should be CV_16SC2 , CV_32FC1 , or CV_32FC2 .
System.Boolean	nnInterpolation	Flag indicating whether the fixed-point maps are used for the nearest-neighbor or for a more complex interpolation.

ConvertPointsFromHomogeneous(IEnumerable<Vec3f>)

converts point coordinates from homogeneous to normal pixel coordinates ((x,y,z)->(x/z, y/z))

Declaration

public static Vec2f[] ConvertPointsFromHomogeneous(IEnumerable<Vec3f> src)

Parameters

Type	Name	Description
IEnumerable<Vec3f>	src	Input vector of N-dimensional points.

Returns

Type	Description
Vec2f[]	Output vector of N-1-dimensional points.

ConvertPointsFromHomogeneous(IEnumerable<Vec4f>)

converts point coordinates from homogeneous to normal pixel coordinates ((x,y,z)->(x/z, y/z))

Declaration

public static Vec3f[] ConvertPointsFromHomogeneous(IEnumerable<Vec4f> src)

Parameters

Type	Name	Description
IEnumerable<Vec4f>	src	Input vector of N-dimensional points.

Returns

Type	Description
Vec3f[]	Output vector of N-1-dimensional points.

ConvertPointsFromHomogeneous(InputArray, OutputArray)

converts point coordinates from homogeneous to normal pixel coordinates ((x,y,z)->(x/z, y/z))

Declaration

public static void ConvertPointsFromHomogeneous(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	Input vector of N-dimensional points.
OutputArray	dst	Output vector of N-1-dimensional points.

ConvertPointsHomogeneous(InputArray, OutputArray)

Converts points to/from homogeneous coordinates.

Declaration

public static void ConvertPointsHomogeneous(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	Input array or vector of 2D, 3D, or 4D points.
OutputArray	dst	Output vector of 2D, 3D, or 4D points.

ConvertPointsToHomogeneous(IEnumerable<Vec2f>)

converts point coordinates from normal pixel coordinates to homogeneous coordinates ((x,y)->(x,y,1))

Declaration

public static Vec3f[] ConvertPointsToHomogeneous(IEnumerable<Vec2f> src)

Parameters

Type	Name	Description
IEnumerable<Vec2f>	src	Input vector of N-dimensional points.

Returns

Type	Description
Vec3f[]	Output vector of N+1-dimensional points.

ConvertPointsToHomogeneous(IEnumerable<Vec3f>)

converts point coordinates from normal pixel coordinates to homogeneous coordinates ((x,y)->(x,y,1))

Declaration

public static Vec4f[] ConvertPointsToHomogeneous(IEnumerable<Vec3f> src)

Parameters

Type	Name	Description
IEnumerable<Vec3f>	src	Input vector of N-dimensional points.

Returns

Type	Description
Vec4f[]	Output vector of N+1-dimensional points.

ConvertPointsToHomogeneous(InputArray, OutputArray)

converts point coordinates from normal pixel coordinates to homogeneous coordinates ((x,y)->(x,y,1))

Declaration

public static void ConvertPointsToHomogeneous(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	Input vector of N-dimensional points.
OutputArray	dst	Output vector of N+1-dimensional points.

ConvertScaleAbs(InputArray, OutputArray, Double, Double)

Scales, computes absolute values and converts the result to 8-bit.

Declaration

public static void ConvertScaleAbs(InputArray src, OutputArray dst, double alpha = 1, double beta = 0)

Parameters

Type	Name	Description
InputArray	src	The source array
OutputArray	dst	The destination array
System.Double	alpha	The optional scale factor. [By default this is 1]
System.Double	beta	The optional delta added to the scaled values. [By default this is 0]

ConvexHull(IEnumerable<Point>, Boolean)

Computes convex hull for a set of 2D points.

Declaration

public static Point[] ConvexHull(IEnumerable<Point> points, bool clockwise = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix
System.Boolean	clockwise	If true, the output convex hull will be oriented clockwise, otherwise it will be oriented counter-clockwise. Here, the usual screen coordinate system is assumed - the origin is at the top-left corner, x axis is oriented to the right, and y axis is oriented downwards.

Returns

Type	Description
OpenCvSharp.Point[]	The output convex hull. It is a vector of points that form the hull (must have the same type as the input points).

ConvexHull(IEnumerable<Point2f>, Boolean)

Computes convex hull for a set of 2D points.

Declaration

public static Point2f[] ConvexHull(IEnumerable<Point2f> points, bool clockwise = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix
System.Boolean	clockwise	If true, the output convex hull will be oriented clockwise, otherwise it will be oriented counter-clockwise. Here, the usual screen coordinate system is assumed - the origin is at the top-left corner, x axis is oriented to the right, and y axis is oriented downwards.

Returns

Type	Description
OpenCvSharp.Point2f[]	The output convex hull. It is a vector of points that form the hull (must have the same type as the input points).

ConvexHull(InputArray, OutputArray, Boolean, Boolean)

Computes convex hull for a set of 2D points.

Declaration

public static void ConvexHull(InputArray points, OutputArray hull, bool clockwise = false, bool returnPoints = true)

Parameters

Type	Name	Description
InputArray	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix
OutputArray	hull	The output convex hull. It is either a vector of points that form the hull (must have the same type as the input points), or a vector of 0-based point indices of the hull points in the original array (since the set of convex hull points is a subset of the original point set).
System.Boolean	clockwise	If true, the output convex hull will be oriented clockwise, otherwise it will be oriented counter-clockwise. Here, the usual screen coordinate system is assumed - the origin is at the top-left corner, x axis is oriented to the right, and y axis is oriented downwards.
System.Boolean	returnPoints

ConvexHullIndices(IEnumerable<Point>, Boolean)

Computes convex hull for a set of 2D points.

Declaration

public static int[] ConvexHullIndices(IEnumerable<Point> points, bool clockwise = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix
System.Boolean	clockwise	If true, the output convex hull will be oriented clockwise, otherwise it will be oriented counter-clockwise. Here, the usual screen coordinate system is assumed - the origin is at the top-left corner, x axis is oriented to the right, and y axis is oriented downwards.

Returns

Type	Description
System.Int32[]	The output convex hull. It is a vector of 0-based point indices of the hull points in the original array (since the set of convex hull points is a subset of the original point set).

ConvexHullIndices(IEnumerable<Point2f>, Boolean)

Computes convex hull for a set of 2D points.

Declaration

public static int[] ConvexHullIndices(IEnumerable<Point2f> points, bool clockwise = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix
System.Boolean	clockwise	If true, the output convex hull will be oriented clockwise, otherwise it will be oriented counter-clockwise. Here, the usual screen coordinate system is assumed - the origin is at the top-left corner, x axis is oriented to the right, and y axis is oriented downwards.

Returns

Type	Description
System.Int32[]	The output convex hull. It is a vector of 0-based point indices of the hull points in the original array (since the set of convex hull points is a subset of the original point set).

ConvexityDefects(IEnumerable<Point>, IEnumerable<Int32>)

Computes the contour convexity defects

Declaration

public static Vec4i[] ConvexityDefects(IEnumerable<Point> contour, IEnumerable<int> convexHull)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	contour	Input contour.
IEnumerable<System.Int32>	convexHull	Convex hull obtained using convexHull() that should contain indices of the contour points that make the hull.

Returns

Type

Description

Vec4i[]

The output vector of convexity defects. Each convexity defect is represented as 4-element integer vector (a.k.a. cv::Vec4i): (start_index, end_index, farthest_pt_index, fixpt_depth), where indices are 0-based indices in the original contour of the convexity defect beginning, end and the farthest point, and fixpt_depth is fixed-point approximation (with 8 fractional bits) of the distance between the farthest contour point and the hull. That is, to get the floating-point value of the depth will be fixpt_depth/256.0.

ConvexityDefects(IEnumerable<Point2f>, IEnumerable<Int32>)

Computes the contour convexity defects

Declaration

public static Vec4i[] ConvexityDefects(IEnumerable<Point2f> contour, IEnumerable<int> convexHull)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	contour	Input contour.
IEnumerable<System.Int32>	convexHull	Convex hull obtained using convexHull() that should contain indices of the contour points that make the hull.

Returns

Type

Description

Vec4i[]

The output vector of convexity defects. Each convexity defect is represented as 4-element integer vector (a.k.a. cv::Vec4i): (start_index, end_index, farthest_pt_index, fixpt_depth), where indices are 0-based indices in the original contour of the convexity defect beginning, end and the farthest point, and fixpt_depth is fixed-point approximation (with 8 fractional bits) of the distance between the farthest contour point and the hull. That is, to get the floating-point value of the depth will be fixpt_depth/256.0.

ConvexityDefects(InputArray, InputArray, OutputArray)

Computes the contour convexity defects

Declaration

public static void ConvexityDefects(InputArray contour, InputArray convexHull, OutputArray convexityDefects)

Parameters

Type	Name	Description
InputArray	contour	Input contour.
InputArray	convexHull	Convex hull obtained using convexHull() that should contain indices of the contour points that make the hull.
OutputArray	convexityDefects	The output vector of convexity defects. Each convexity defect is represented as 4-element integer vector (a.k.a. cv::Vec4i): (start_index, end_index, farthest_pt_index, fixpt_depth), where indices are 0-based indices in the original contour of the convexity defect beginning, end and the farthest point, and fixpt_depth is fixed-point approximation (with 8 fractional bits) of the distance between the farthest contour point and the hull. That is, to get the floating-point value of the depth will be fixpt_depth/256.0.

CopyMakeBorder(InputArray, OutputArray, Int32, Int32, Int32, Int32, BorderTypes, Nullable<Scalar>)

Forms a border around the image

Declaration

public static void CopyMakeBorder(InputArray src, OutputArray dst, int top, int bottom, int left, int right, BorderTypes borderType, Scalar? value = null)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image; will have the same type as src and the size Size(src.cols+left+right, src.rows+top+bottom)
System.Int32	top	Specify how much pixels in each direction from the source image rectangle one needs to extrapolate
System.Int32	bottom	Specify how much pixels in each direction from the source image rectangle one needs to extrapolate
System.Int32	left	Specify how much pixels in each direction from the source image rectangle one needs to extrapolate
System.Int32	right	Specify how much pixels in each direction from the source image rectangle one needs to extrapolate
BorderTypes	borderType	The border type
System.Nullable<OpenCvSharp.Scalar>	value	The border value if borderType == Constant

CopyTo(InputArray, OutputArray, InputArray)

Copies the matrix to another one. When the operation mask is specified, if the Mat::create call shown above reallocates the matrix, the newly allocated matrix is initialized with all zeros before copying the data.

Declaration

public static void CopyTo(InputArray src, OutputArray dst, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	Source matrix.
OutputArray	dst	Destination matrix. If it does not have a proper size or type before the operation, it is reallocated.
InputArray	mask	Operation mask of the same size as *this. Its non-zero elements indicate which matrix elements need to be copied.The mask has to be of type CV_8U and can have 1 or multiple channels.

CornerEigenValsAndVecs(InputArray, OutputArray, Int32, Int32, BorderTypes)

computes both eigenvalues and the eigenvectors of 2x2 derivative covariation matrix at each pixel. The output is stored as 6-channel matrix.

Declaration

public static void CornerEigenValsAndVecs(InputArray src, OutputArray dst, int blockSize, int ksize, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src
OutputArray	dst
System.Int32	blockSize
System.Int32	ksize
BorderTypes	borderType

CornerHarris(InputArray, OutputArray, Int32, Int32, Double, BorderTypes)

Harris corner detector.

Declaration

public static void CornerHarris(InputArray src, OutputArray dst, int blockSize, int ksize, double k, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	Input single-channel 8-bit or floating-point image.
OutputArray	dst	Image to store the Harris detector responses. It has the type CV_32FC1 and the same size as src.
System.Int32	blockSize	Neighborhood size (see the details on #cornerEigenValsAndVecs ).
System.Int32	ksize	Aperture parameter for the Sobel operator.
System.Double	k	Harris detector free parameter. See the formula above.
BorderTypes	borderType	Pixel extrapolation method. See #BorderTypes. #BORDER_WRAP is not supported.

CornerMinEigenVal(InputArray, OutputArray, Int32, Int32, BorderTypes)

Calculates the minimal eigenvalue of gradient matrices for corner detection.

Declaration

public static void CornerMinEigenVal(InputArray src, OutputArray dst, int blockSize, int ksize = 3, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	Input single-channel 8-bit or floating-point image.
OutputArray	dst	Image to store the minimal eigenvalues. It has the type CV_32FC1 and the same size as src .
System.Int32	blockSize	Neighborhood size (see the details on #cornerEigenValsAndVecs ).
System.Int32	ksize	Aperture parameter for the Sobel operator.
BorderTypes	borderType	Pixel extrapolation method. See #BorderTypes. #BORDER_WRAP is not supported.

CornerSubPix(InputArray, IEnumerable<Point2f>, Size, Size, TermCriteria)

adjusts the corner locations with sub-pixel accuracy to maximize the certain cornerness criteria

Declaration

public static Point2f[] CornerSubPix(InputArray image, IEnumerable<Point2f> inputCorners, Size winSize, Size zeroZone, TermCriteria criteria)

Parameters

Type	Name	Description
InputArray	image	Input image.
IEnumerable<OpenCvSharp.Point2f>	inputCorners	Initial coordinates of the input corners and refined coordinates provided for output.
OpenCvSharp.Size	winSize	Half of the side length of the search window.
OpenCvSharp.Size	zeroZone	Half of the size of the dead region in the middle of the search zone over which the summation in the formula below is not done. It is used sometimes to avoid possible singularities of the autocorrelation matrix. The value of (-1,-1) indicates that there is no such a size.
OpenCvSharp.TermCriteria	criteria	Criteria for termination of the iterative process of corner refinement. That is, the process of corner position refinement stops either after criteria.maxCount iterations or when the corner position moves by less than criteria.epsilon on some iteration.

Returns

Type	Description
OpenCvSharp.Point2f[]

CorrectMatches(InputArray, InputArray, InputArray, OutputArray, OutputArray)

Refines coordinates of corresponding points.

Declaration

public static void CorrectMatches(InputArray F, InputArray points1, InputArray points2, OutputArray newPoints1, OutputArray newPoints2)

Parameters

Type	Name	Description
InputArray	F	3x3 fundamental matrix.
InputArray	points1	1xN array containing the first set of points.
InputArray	points2	1xN array containing the second set of points.
OutputArray	newPoints1	The optimized points1.
OutputArray	newPoints2	The optimized points2.

CorrectMatches(Double[,], IEnumerable<Point2d>, IEnumerable<Point2d>, out Point2d[], out Point2d[])

Refines coordinates of corresponding points.

Declaration

public static void CorrectMatches(double[, ] F, IEnumerable<Point2d> points1, IEnumerable<Point2d> points2, out Point2d[] newPoints1, out Point2d[] newPoints2)

Parameters

Type	Name	Description
System.Double[,]	F	3x3 fundamental matrix.
IEnumerable<OpenCvSharp.Point2d>	points1	1xN array containing the first set of points.
IEnumerable<OpenCvSharp.Point2d>	points2	1xN array containing the second set of points.
OpenCvSharp.Point2d[]	newPoints1	The optimized points1.
OpenCvSharp.Point2d[]	newPoints2	The optimized points2.

CountNonZero(InputArray)

computes the number of nonzero array elements

Declaration

public static int CountNonZero(InputArray mtx)

Parameters

Type	Name	Description
InputArray	mtx	Single-channel array

Returns

Type	Description
System.Int32	number of non-zero elements in mtx

CreateCLAHE(Double, Nullable<Size>)

Creates a predefined CLAHE object

Declaration

public static CLAHE CreateCLAHE(double clipLimit = 40, Size? tileGridSize = null)

Parameters

Type	Name	Description
System.Double	clipLimit
System.Nullable<OpenCvSharp.Size>	tileGridSize

Returns

Type	Description
CLAHE

CreateFrameSource_Camera(Int32)

Declaration

public static FrameSource CreateFrameSource_Camera(int deviceId)

Parameters

Type	Name	Description
System.Int32	deviceId

Returns

Type	Description
FrameSource

CreateFrameSource_Empty()

Declaration

public static FrameSource CreateFrameSource_Empty()

Returns

Type	Description
FrameSource

CreateFrameSource_Video(String)

Declaration

public static FrameSource CreateFrameSource_Video(string fileName)

Parameters

Type	Name	Description
System.String	fileName

Returns

Type	Description
FrameSource

CreateFrameSource_Video_CUDA(String)

Declaration

public static FrameSource CreateFrameSource_Video_CUDA(string fileName)

Parameters

Type	Name	Description
System.String	fileName

Returns

Type	Description
FrameSource

CreateHanningWindow(InputOutputArray, Size, MatType)

Computes a Hanning window coefficients in two dimensions.

Declaration

public static void CreateHanningWindow(InputOutputArray dst, Size winSize, MatType type)

Parameters

Type	Name	Description
InputOutputArray	dst	Destination array to place Hann coefficients in
OpenCvSharp.Size	winSize	The window size specifications
OpenCvSharp.MatType	type	Created array type

CreateOptFlow_Brox_GPU()

Declaration

public static DenseOpticalFlowExt CreateOptFlow_Brox_GPU()

Returns

Type	Description
DenseOpticalFlowExt

CreateOptFlow_DualTVL1_GPU()

Declaration

public static DenseOpticalFlowExt CreateOptFlow_DualTVL1_GPU()

Returns

Type	Description
DenseOpticalFlowExt

CreateOptFlow_Farneback()

Declaration

public static DenseOpticalFlowExt CreateOptFlow_Farneback()

Returns

Type	Description
DenseOpticalFlowExt

CreateOptFlow_Farneback_GPU()

Declaration

public static DenseOpticalFlowExt CreateOptFlow_Farneback_GPU()

Returns

Type	Description
DenseOpticalFlowExt

CreateOptFlow_PyrLK_GPU()

Declaration

public static DenseOpticalFlowExt CreateOptFlow_PyrLK_GPU()

Returns

Type	Description
DenseOpticalFlowExt

CreateSuperResolution_BTVL1()

Create Bilateral TV-L1 Super Resolution.

Declaration

public static SuperResolution CreateSuperResolution_BTVL1()

Returns

Type	Description
SuperResolution

CreateSuperResolution_BTVL1_CUDA()

Create Bilateral TV-L1 Super Resolution.

Declaration

public static SuperResolution CreateSuperResolution_BTVL1_CUDA()

Returns

Type	Description
SuperResolution

CreateTrackbar(String, String, Int32, TrackbarCallbackNative, IntPtr)

Creates a trackbar and attaches it to the specified window. The function createTrackbar creates a trackbar(a slider or range control) with the specified name and range, assigns a variable value to be a position synchronized with the trackbar and specifies the callback function onChange to be called on the trackbar position change.The created trackbar is displayed in the specified window winName.

Declaration

public static int CreateTrackbar(string trackbarName, string winName, int count, TrackbarCallbackNative onChange = null, IntPtr userData = null)

Parameters

Type	Name	Description
System.String	trackbarName	Name of the created trackbar.
System.String	winName	Name of the window that will be used as a parent of the created trackbar.
System.Int32	count	Maximal position of the slider. The minimal position is always 0.
TrackbarCallbackNative	onChange	Pointer to the function to be called every time the slider changes position. This function should be prototyped as void Foo(int, void*); , where the first parameter is the trackbar position and the second parameter is the user data(see the next parameter). If the callback is the NULL pointer, no callbacks are called, but only value is updated.
IntPtr	userData	User data that is passed as is to the callback. It can be used to handle trackbar events without using global variables.

Returns

Type	Description
System.Int32

CreateTrackbar(String, String, ref Int32, Int32, TrackbarCallbackNative, IntPtr)

Creates a trackbar and attaches it to the specified window. The function createTrackbar creates a trackbar(a slider or range control) with the specified name and range, assigns a variable value to be a position synchronized with the trackbar and specifies the callback function onChange to be called on the trackbar position change.The created trackbar is displayed in the specified window winName.

Declaration

public static int CreateTrackbar(string trackbarName, string winName, ref int value, int count, TrackbarCallbackNative onChange = null, IntPtr userData = null)

Parameters

Type	Name	Description
System.String	trackbarName	Name of the created trackbar.
System.String	winName	Name of the window that will be used as a parent of the created trackbar.
System.Int32	value	Optional pointer to an integer variable whose value reflects the position of the slider.Upon creation, the slider position is defined by this variable.
System.Int32	count	Maximal position of the slider. The minimal position is always 0.
TrackbarCallbackNative	onChange	Pointer to the function to be called every time the slider changes position. This function should be prototyped as void Foo(int, void*); , where the first parameter is the trackbar position and the second parameter is the user data(see the next parameter). If the callback is the NULL pointer, no callbacks are called, but only value is updated.
IntPtr	userData	User data that is passed as is to the callback. It can be used to handle trackbar events without using global variables.

Returns

Type	Description
System.Int32

CubeRoot(Single)

computes cube root of the argument

Declaration

public static float CubeRoot(float val)

Parameters

Type	Name	Description
System.Single	val

Returns

Type	Description
System.Single

CvtColor(InputArray, OutputArray, ColorConversionCodes, Int32)

Converts image from one color space to another

Declaration

public static void CvtColor(InputArray src, OutputArray dst, ColorConversionCodes code, int dstCn = 0)

Parameters

Type	Name	Description
InputArray	src	The source image, 8-bit unsigned, 16-bit unsigned or single-precision floating-point
OutputArray	dst	The destination image; will have the same size and the same depth as src
ColorConversionCodes	code	The color space conversion code
System.Int32	dstCn	The number of channels in the destination image; if the parameter is 0, the number of the channels will be derived automatically from src and the code

CvtColorTwoPlane(InputArray, InputArray, OutputArray, ColorConversionCodes)

Converts an image from one color space to another where the source image is stored in two planes. This function only supports YUV420 to RGB conversion as of now.

Declaration

public static void CvtColorTwoPlane(InputArray src1, InputArray src2, OutputArray dst, ColorConversionCodes code)

Parameters

Type	Name	Description
InputArray	src1	8-bit image (#CV_8U) of the Y plane.
InputArray	src2	image containing interleaved U/V plane.
OutputArray	dst	output image.
ColorConversionCodes	code	Specifies the type of conversion. It can take any of the following values: #COLOR_YUV2BGR_NV12 #COLOR_YUV2RGB_NV12 #COLOR_YUV2BGRA_NV12 #COLOR_YUV2RGBA_NV12 #COLOR_YUV2BGR_NV21 #COLOR_YUV2RGB_NV21 #COLOR_YUV2BGRA_NV21 #COLOR_YUV2RGBA_NV21

Dct(InputArray, OutputArray, DctFlags)

Performs forward or inverse 1D or 2D Discrete Cosine Transformation

Declaration

public static void Dct(InputArray src, OutputArray dst, DctFlags flags = DctFlags.None)

Parameters

Type	Name	Description
InputArray	src	The source floating-point array
OutputArray	dst	The destination array; will have the same size and same type as src
DctFlags	flags	Transformation flags, a combination of DctFlag2 values

Decolor(InputArray, OutputArray, OutputArray)

Transforms a color image to a grayscale image. It is a basic tool in digital printing, stylized black-and-white photograph rendering, and in many single channel image processing applications @cite CL12 .

Declaration

public static void Decolor(InputArray src, OutputArray grayscale, OutputArray colorBoost)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
OutputArray	grayscale	Output 8-bit 1-channel image.
OutputArray	colorBoost	Output 8-bit 3-channel image.

DecomposeHomographyMat(InputArray, InputArray, out Mat[], out Mat[], out Mat[])

Decompose a homography matrix to rotation(s), translation(s) and plane normal(s).

Declaration

public static int DecomposeHomographyMat(InputArray h, InputArray k, out Mat[] rotations, out Mat[] translations, out Mat[] normals)

Parameters

Type	Name	Description
InputArray	h	The input homography matrix between two images.
InputArray	k	The input intrinsic camera calibration matrix.
Mat[]	rotations	Array of rotation matrices.
Mat[]	translations	Array of translation matrices.
Mat[]	normals	Array of plane normal matrices.

Returns

Type	Description
System.Int32

DecomposeProjectionMatrix(InputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray)

Decomposes the projection matrix into camera matrix and the rotation martix and the translation vector

Declaration

public static void DecomposeProjectionMatrix(InputArray projMatrix, OutputArray cameraMatrix, OutputArray rotMatrix, OutputArray transVect, OutputArray rotMatrixX = null, OutputArray rotMatrixY = null, OutputArray rotMatrixZ = null, OutputArray eulerAngles = null)

Parameters

Type	Name	Description
InputArray	projMatrix	3x4 input projection matrix P.
OutputArray	cameraMatrix	Output 3x3 camera matrix K.
OutputArray	rotMatrix	Output 3x3 external rotation matrix R.
OutputArray	transVect	Output 4x1 translation vector T.
OutputArray	rotMatrixX	Optional 3x3 rotation matrix around x-axis.
OutputArray	rotMatrixY	Optional 3x3 rotation matrix around y-axis.
OutputArray	rotMatrixZ	Optional 3x3 rotation matrix around z-axis.
OutputArray	eulerAngles	ptional three-element vector containing three Euler angles of rotation in degrees.

DecomposeProjectionMatrix(Double[,], out Double[,], out Double[,], out Double[])

Decomposes the projection matrix into camera matrix and the rotation martix and the translation vector

Declaration

public static void DecomposeProjectionMatrix(double[, ] projMatrix, out double[, ] cameraMatrix, out double[, ] rotMatrix, out double[] transVect)

Parameters

Type	Name	Description
System.Double[,]	projMatrix	3x4 input projection matrix P.
System.Double[,]	cameraMatrix	Output 3x3 camera matrix K.
System.Double[,]	rotMatrix	Output 3x3 external rotation matrix R.
System.Double[]	transVect	Output 4x1 translation vector T.

DecomposeProjectionMatrix(Double[,], out Double[,], out Double[,], out Double[], out Double[,], out Double[,], out Double[,], out Double[])

Decomposes the projection matrix into camera matrix and the rotation martix and the translation vector

Declaration

public static void DecomposeProjectionMatrix(double[, ] projMatrix, out double[, ] cameraMatrix, out double[, ] rotMatrix, out double[] transVect, out double[, ] rotMatrixX, out double[, ] rotMatrixY, out double[, ] rotMatrixZ, out double[] eulerAngles)

Parameters

Type	Name	Description
System.Double[,]	projMatrix	3x4 input projection matrix P.
System.Double[,]	cameraMatrix	Output 3x3 camera matrix K.
System.Double[,]	rotMatrix	Output 3x3 external rotation matrix R.
System.Double[]	transVect	Output 4x1 translation vector T.
System.Double[,]	rotMatrixX	Optional 3x3 rotation matrix around x-axis.
System.Double[,]	rotMatrixY	Optional 3x3 rotation matrix around y-axis.
System.Double[,]	rotMatrixZ	Optional 3x3 rotation matrix around z-axis.
System.Double[]	eulerAngles	ptional three-element vector containing three Euler angles of rotation in degrees.

Demosaicing(InputArray, OutputArray, ColorConversionCodes, Int32)

main function for all demosaicing processes

Declaration

public static void Demosaicing(InputArray src, OutputArray dst, ColorConversionCodes code, int dstCn = 0)

Parameters

Type	Name	Description
InputArray	src	input image: 8-bit unsigned or 16-bit unsigned.
OutputArray	dst	output image of the same size and depth as src.
ColorConversionCodes	code	Color space conversion code (see the description below).
System.Int32	dstCn	number of channels in the destination image; if the parameter is 0, the number of the channels is derived automatically from src and code.

Remarks

The function can do the following transformations:

• Demosaicing using bilinear interpolation

#COLOR_BayerBG2BGR , #COLOR_BayerGB2BGR , #COLOR_BayerRG2BGR , #COLOR_BayerGR2BGR #COLOR_BayerBG2GRAY , #COLOR_BayerGB2GRAY , #COLOR_BayerRG2GRAY , #COLOR_BayerGR2GRAY

• Demosaicing using Variable Number of Gradients.

#COLOR_BayerBG2BGR_VNG , #COLOR_BayerGB2BGR_VNG , #COLOR_BayerRG2BGR_VNG , #COLOR_BayerGR2BGR_VNG

• Edge-Aware Demosaicing.

#COLOR_BayerBG2BGR_EA , #COLOR_BayerGB2BGR_EA , #COLOR_BayerRG2BGR_EA , #COLOR_BayerGR2BGR_EA

• Demosaicing with alpha channel

COLOR_BayerBG2BGRA , #COLOR_BayerGB2BGRA , #COLOR_BayerRG2BGRA , #COLOR_BayerGR2BGRA

DenoiseTVL1(IEnumerable<Mat>, Mat, Double, Int32)

Primal-dual algorithm is an algorithm for solving special types of variational problems (that is, finding a function to minimize some functional). As the image denoising, in particular, may be seen as the variational problem, primal-dual algorithm then can be used to perform denoising and this is exactly what is implemented.

Declaration

public static void DenoiseTVL1(IEnumerable<Mat> observations, Mat result, double lambda = 1, int niters = 30)

Parameters

Type	Name	Description
IEnumerable<Mat>	observations	This array should contain one or more noised versions of the image that is to be restored.
Mat	result	Here the denoised image will be stored. There is no need to do pre-allocation of storage space, as it will be automatically allocated, if necessary.
System.Double	lambda	Corresponds to \f$\lambda\f$ in the formulas above. As it is enlarged, the smooth (blurred) images are treated more favorably than detailed (but maybe more noised) ones. Roughly speaking, as it becomes smaller, the result will be more blur but more sever outliers will be removed.
System.Int32	niters	Number of iterations that the algorithm will run. Of course, as more iterations as better, but it is hard to quantitatively refine this statement, so just use the default and increase it if the results are poor.

DestroyAllWindows()

Destroys all of the HighGUI windows.

Declaration

public static void DestroyAllWindows()

DestroyWindow(String)

Destroys the specified window.

Declaration

public static void DestroyWindow(string winName)

Parameters

Type	Name	Description
System.String	winName

DetailEnhance(InputArray, OutputArray, Single, Single)

This filter enhances the details of a particular image.

Declaration

public static void DetailEnhance(InputArray src, OutputArray dst, float sigmaS = 10F, float sigmaR = 0.15F)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
OutputArray	dst	Output image with the same size and type as src.
System.Single	sigmaS	Range between 0 to 200.
System.Single	sigmaR	Range between 0 to 1.

Determinant(InputArray)

computes determinant of a square matrix

Declaration

public static double Determinant(InputArray mtx)

Parameters

Type	Name	Description
InputArray	mtx	The input matrix; must have CV_32FC1 or CV_64FC1 type and square size

Returns

Type	Description
System.Double	determinant of the specified matrix.

Dft(InputArray, OutputArray, DftFlags, Int32)

Performs a forward Discrete Fourier transform of 1D or 2D floating-point array.

Declaration

public static void Dft(InputArray src, OutputArray dst, DftFlags flags = DftFlags.None, int nonzeroRows = 0)

Parameters

Type	Name	Description
InputArray	src	The source array, real or complex
OutputArray	dst	The destination array, which size and type depends on the flags
DftFlags	flags	Transformation flags, a combination of the DftFlag2 values
System.Int32	nonzeroRows	When the parameter != 0, the function assumes that only the first nonzeroRows rows of the input array ( DFT_INVERSE is not set) or only the first nonzeroRows of the output array ( DFT_INVERSE is set) contain non-zeros, thus the function can handle the rest of the rows more efficiently and thus save some time. This technique is very useful for computing array cross-correlation or convolution using DFT

Dilate(InputArray, OutputArray, InputArray, Nullable<Point>, Int32, BorderTypes, Nullable<Scalar>)

Dilates an image by using a specific structuring element.

Declaration

public static void Dilate(InputArray src, OutputArray dst, InputArray element, Point? anchor = null, int iterations = 1, BorderTypes borderType = BorderTypes.Constant, Scalar? borderValue = null)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image. It will have the same size and the same type as src
InputArray	element	The structuring element used for dilation. If element=new Mat() , a 3x3 rectangular structuring element is used
System.Nullable<OpenCvSharp.Point>	anchor	Position of the anchor within the element. The default value (-1, -1) means that the anchor is at the element center
System.Int32	iterations	The number of times dilation is applied. [By default this is 1]
BorderTypes	borderType	The pixel extrapolation method. [By default this is BorderType.Constant]
System.Nullable<OpenCvSharp.Scalar>	borderValue	The border value in case of a constant border. The default value has a special meaning. [By default this is CvCpp.MorphologyDefaultBorderValue()]

DistanceTransform(InputArray, OutputArray, DistanceTypes, DistanceTransformMasks, Int32)

computes the distance transform map

Declaration

public static void DistanceTransform(InputArray src, OutputArray dst, DistanceTypes distanceType, DistanceTransformMasks maskSize, int dstType = default(int))

Parameters

Type	Name	Description
InputArray	src	8-bit, single-channel (binary) source image.
OutputArray	dst	Output image with calculated distances. It is a 8-bit or 32-bit floating-point, single-channel image of the same size as src.
DistanceTypes	distanceType	Type of distance
DistanceTransformMasks	maskSize	Size of the distance transform mask, see #DistanceTransformMasks. In case of the #DIST_L1 or #DIST_C distance type, the parameter is forced to 3 because a 3x3 mask gives the same result as 5x5 or any larger aperture.
System.Int32	dstType	Type of output image. It can be MatType.CV_8U or MatType.CV_32F. Type CV_8U can be used only for the first variant of the function and distanceType == #DIST_L1.

DistanceTransformWithLabels(InputArray, OutputArray, OutputArray, DistanceTypes, DistanceTransformMasks, DistanceTransformLabelTypes)

Calculates the distance to the closest zero pixel for each pixel of the source image.

Declaration

public static void DistanceTransformWithLabels(InputArray src, OutputArray dst, OutputArray labels, DistanceTypes distanceType, DistanceTransformMasks maskSize, DistanceTransformLabelTypes labelType = DistanceTransformLabelTypes.CComp)

Parameters

Type	Name	Description
InputArray	src	8-bit, single-channel (binary) source image.
OutputArray	dst	Output image with calculated distances. It is a 8-bit or 32-bit floating-point, single-channel image of the same size as src.
OutputArray	labels	Output 2D array of labels (the discrete Voronoi diagram). It has the type CV_32SC1 and the same size as src.
DistanceTypes	distanceType	Type of distance
DistanceTransformMasks	maskSize	Size of the distance transform mask, see #DistanceTransformMasks. #DIST_MASK_PRECISE is not supported by this variant. In case of the #DIST_L1 or #DIST_C distance type, the parameter is forced to 3 because a 3x3 mask gives the same result as 5x5 or any larger aperture.
DistanceTransformLabelTypes	labelType	Type of the label array to build

Divide(InputArray, InputArray, OutputArray, Double, Nullable<MatType>)

Performs per-element division of two arrays or a scalar by an array.

Declaration

public static void Divide(InputArray src1, InputArray src2, OutputArray dst, double scale = 1, MatType? dtype = null)

Parameters

Type	Name	Description
InputArray	src1	The first source array
InputArray	src2	The second source array; should have the same size and same type as src1
OutputArray	dst	The destination array; will have the same size and same type as src2
System.Double	scale	Scale factor [By default this is 1]
System.Nullable<OpenCvSharp.MatType>	dtype

Divide(Double, InputArray, OutputArray, Int32)

Performs per-element division of two arrays or a scalar by an array.

Declaration

public static void Divide(double scale, InputArray src2, OutputArray dst, int dtype = -1)

Parameters

Type	Name	Description
System.Double	scale	Scale factor
InputArray	src2	The first source array
OutputArray	dst	The destination array; will have the same size and same type as src2
System.Int32	dtype

DrawChessboardCorners(InputOutputArray, Size, IEnumerable<Point2f>, Boolean)

Renders the detected chessboard corners.

Declaration

public static void DrawChessboardCorners(InputOutputArray image, Size patternSize, IEnumerable<Point2f> corners, bool patternWasFound)

Parameters

Type	Name	Description
InputOutputArray	image	Destination image. It must be an 8-bit color image.
OpenCvSharp.Size	patternSize	Number of inner corners per a chessboard row and column (patternSize = cv::Size(points_per_row,points_per_column)).
IEnumerable<OpenCvSharp.Point2f>	corners	Array of detected corners, the output of findChessboardCorners.
System.Boolean	patternWasFound	Parameter indicating whether the complete board was found or not. The return value of findChessboardCorners() should be passed here.

DrawChessboardCorners(InputOutputArray, Size, InputArray, Boolean)

Renders the detected chessboard corners.

Declaration

public static void DrawChessboardCorners(InputOutputArray image, Size patternSize, InputArray corners, bool patternWasFound)

Parameters

Type	Name	Description
InputOutputArray	image	Destination image. It must be an 8-bit color image.
OpenCvSharp.Size	patternSize	Number of inner corners per a chessboard row and column (patternSize = cv::Size(points_per_row,points_per_column)).
InputArray	corners	Array of detected corners, the output of findChessboardCorners.
System.Boolean	patternWasFound	Parameter indicating whether the complete board was found or not. The return value of findChessboardCorners() should be passed here.

DrawContours(InputOutputArray, IEnumerable<IEnumerable<Point>>, Int32, Scalar, Int32, LineTypes, Nullable<IEnumerable<HierarchyIndex>>, Int32, Nullable<Point>)

draws contours in the image

Declaration

public static void DrawContours(InputOutputArray image, IEnumerable<IEnumerable<Point>> contours, int contourIdx, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, IEnumerable<HierarchyIndex>? hierarchy = null, int maxLevel = 2147483647, Point? offset = null)

Parameters

Type	Name	Description
InputOutputArray	image	Destination image.
IEnumerable<IEnumerable<OpenCvSharp.Point>>	contours	All the input contours. Each contour is stored as a point vector.
System.Int32	contourIdx	Parameter indicating a contour to draw. If it is negative, all the contours are drawn.
OpenCvSharp.Scalar	color	Color of the contours.
System.Int32	thickness	Thickness of lines the contours are drawn with. If it is negative (for example, thickness=CV_FILLED ), the contour interiors are drawn.
LineTypes	lineType	Line connectivity.
System.Nullable<IEnumerable<HierarchyIndex>>	hierarchy	Optional information about hierarchy. It is only needed if you want to draw only some of the contours
System.Int32	maxLevel	Maximal level for drawn contours. If it is 0, only the specified contour is drawn. If it is 1, the function draws the contour(s) and all the nested contours. If it is 2, the function draws the contours, all the nested contours, all the nested-to-nested contours, and so on. This parameter is only taken into account when there is hierarchy available.
System.Nullable<OpenCvSharp.Point>	offset	Optional contour shift parameter. Shift all the drawn contours by the specified offset = (dx, dy)

DrawContours(InputOutputArray, IEnumerable<Mat>, Int32, Scalar, Int32, LineTypes, Mat, Int32, Nullable<Point>)

draws contours in the image

Declaration

public static void DrawContours(InputOutputArray image, IEnumerable<Mat> contours, int contourIdx, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, Mat hierarchy = null, int maxLevel = 2147483647, Point? offset = null)

Parameters

Type	Name	Description
InputOutputArray	image	Destination image.
IEnumerable<Mat>	contours	All the input contours. Each contour is stored as a point vector.
System.Int32	contourIdx	Parameter indicating a contour to draw. If it is negative, all the contours are drawn.
OpenCvSharp.Scalar	color	Color of the contours.
System.Int32	thickness	Thickness of lines the contours are drawn with. If it is negative (for example, thickness=CV_FILLED ), the contour interiors are drawn.
LineTypes	lineType	Line connectivity.
Mat	hierarchy	Optional information about hierarchy. It is only needed if you want to draw only some of the contours
System.Int32	maxLevel	Maximal level for drawn contours. If it is 0, only the specified contour is drawn. If it is 1, the function draws the contour(s) and all the nested contours. If it is 2, the function draws the contours, all the nested contours, all the nested-to-nested contours, and so on. This parameter is only taken into account when there is hierarchy available.
System.Nullable<OpenCvSharp.Point>	offset	Optional contour shift parameter. Shift all the drawn contours by the specified offset = (dx, dy)

DrawFrameAxes(InputOutputArray, InputArray, InputArray, InputArray, InputArray, Single, Int32)

Draw axes of the world/object coordinate system from pose estimation.

Declaration

public static void DrawFrameAxes(InputOutputArray image, InputArray cameraMatrix, InputArray distCoeffs, InputArray rvec, InputArray tvec, float length, int thickness = 3)

Parameters

Type	Name	Description
InputOutputArray	image	Input/output image. It must have 1 or 3 channels. The number of channels is not altered.
InputArray	cameraMatrix	Input 3x3 floating-point matrix of camera intrinsic parameters.
InputArray	distCoeffs	Input vector of distortion coefficients \f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6[, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of 4, 5, 8, 12 or 14 elements.If the vector is empty, the zero distortion coefficients are assumed.
InputArray	rvec	Rotation vector (see @ref Rodrigues ) that, together with tvec , brings points from the model coordinate system to the camera coordinate system.
InputArray	tvec	Translation vector.
System.Single	length	Length of the painted axes in the same unit than tvec (usually in meters).
System.Int32	thickness	Line thickness of the painted axes.

Remarks

This function draws the axes of the world/object coordinate system w.r.t. to the camera frame. OX is drawn in red, OY in green and OZ in blue.

DrawKeypoints(InputArray, IEnumerable<KeyPoint>, InputOutputArray, Nullable<Scalar>, DrawMatchesFlags)

Draw keypoints.

Declaration

public static void DrawKeypoints(InputArray image, IEnumerable<KeyPoint> keypoints, InputOutputArray outImage, Scalar? color = null, DrawMatchesFlags flags = DrawMatchesFlags.Default)

Parameters

Type	Name	Description
InputArray	image	Source image.
IEnumerable<OpenCvSharp.KeyPoint>	keypoints	Keypoints from the source image.
InputOutputArray	outImage	Output image. Its content depends on the flags value defining what is drawn in the output image. See possible flags bit values below.
System.Nullable<OpenCvSharp.Scalar>	color	Color of keypoints.
DrawMatchesFlags	flags	Flags setting drawing features. Possible flags bit values are defined by DrawMatchesFlags.

DrawMarker(InputOutputArray, Point, Scalar, MarkerTypes, Int32, Int32, LineTypes)

Draws a marker on a predefined position in an image.

The function cv::drawMarker draws a marker on a given position in the image.For the moment several marker types are supported, see #MarkerTypes for more information.

Declaration

public static void DrawMarker(InputOutputArray img, Point position, Scalar color, MarkerTypes markerType = MarkerTypes.Cross, int markerSize = 20, int thickness = 1, LineTypes lineType = LineTypes.Link8)

Parameters

Type	Name	Description
InputOutputArray	img	Image.
OpenCvSharp.Point	position	The point where the crosshair is positioned.
OpenCvSharp.Scalar	color	Line color.
MarkerTypes	markerType	The specific type of marker you want to use.
System.Int32	markerSize	The length of the marker axis [default = 20 pixels]
System.Int32	thickness	Line thickness.
LineTypes	lineType	Type of the line.

DrawMatches(Mat, IEnumerable<KeyPoint>, Mat, IEnumerable<KeyPoint>, IEnumerable<DMatch>, Mat, Nullable<Scalar>, Nullable<Scalar>, Nullable<IEnumerable<Byte>>, DrawMatchesFlags)

Draws the found matches of keypoints from two images.

Declaration

public static void DrawMatches(Mat img1, IEnumerable<KeyPoint> keypoints1, Mat img2, IEnumerable<KeyPoint> keypoints2, IEnumerable<DMatch> matches1To2, Mat outImg, Scalar? matchColor = null, Scalar? singlePointColor = null, IEnumerable<byte>? matchesMask = null, DrawMatchesFlags flags = DrawMatchesFlags.Default)

Parameters

Type	Name	Description
Mat	img1	First source image.
IEnumerable<OpenCvSharp.KeyPoint>	keypoints1	Keypoints from the first source image.
Mat	img2	Second source image.
IEnumerable<OpenCvSharp.KeyPoint>	keypoints2	Keypoints from the second source image.
IEnumerable<OpenCvSharp.DMatch>	matches1To2	Matches from the first image to the second one, which means that keypoints1[i] has a corresponding point in keypoints2[matches[i]] .
Mat	outImg	Output image. Its content depends on the flags value defining what is drawn in the output image. See possible flags bit values below.
System.Nullable<OpenCvSharp.Scalar>	matchColor	Color of matches (lines and connected keypoints). If matchColor==Scalar::all(-1), the color is generated randomly.
System.Nullable<OpenCvSharp.Scalar>	singlePointColor	Color of single keypoints (circles), which means that keypoints do not have the matches. If singlePointColor==Scalar::all(-1) , the color is generated randomly.
System.Nullable<IEnumerable<System.Byte>>	matchesMask	Mask determining which matches are drawn. If the mask is empty, all matches are drawn.
DrawMatchesFlags	flags	Flags setting drawing features. Possible flags bit values are defined by DrawMatchesFlags.

DrawMatchesKnn(Mat, IEnumerable<KeyPoint>, Mat, IEnumerable<KeyPoint>, IEnumerable<IEnumerable<DMatch>>, Mat, Nullable<Scalar>, Nullable<Scalar>, Nullable<IEnumerable<IEnumerable<Byte>>>, DrawMatchesFlags)

Draws the found matches of keypoints from two images.

Declaration

public static void DrawMatchesKnn(Mat img1, IEnumerable<KeyPoint> keypoints1, Mat img2, IEnumerable<KeyPoint> keypoints2, IEnumerable<IEnumerable<DMatch>> matches1To2, Mat outImg, Scalar? matchColor = null, Scalar? singlePointColor = null, IEnumerable<IEnumerable<byte>>? matchesMask = null, DrawMatchesFlags flags = DrawMatchesFlags.Default)

Parameters

Type	Name	Description
Mat	img1	First source image.
IEnumerable<OpenCvSharp.KeyPoint>	keypoints1	Keypoints from the first source image.
Mat	img2	Second source image.
IEnumerable<OpenCvSharp.KeyPoint>	keypoints2	Keypoints from the second source image.
IEnumerable<IEnumerable<OpenCvSharp.DMatch>>	matches1To2	Matches from the first image to the second one, which means that keypoints1[i] has a corresponding point in keypoints2[matches[i]] .
Mat	outImg	Output image. Its content depends on the flags value defining what is drawn in the output image. See possible flags bit values below.
System.Nullable<OpenCvSharp.Scalar>	matchColor	Color of matches (lines and connected keypoints). If matchColor==Scalar::all(-1), the color is generated randomly.
System.Nullable<OpenCvSharp.Scalar>	singlePointColor	Color of single keypoints (circles), which means that keypoints do not have the matches. If singlePointColor==Scalar::all(-1) , the color is generated randomly.
System.Nullable<IEnumerable<IEnumerable<System.Byte>>>	matchesMask	Mask determining which matches are drawn. If the mask is empty, all matches are drawn.
DrawMatchesFlags	flags	Flags setting drawing features. Possible flags bit values are defined by DrawMatchesFlags.

EdgePreservingFilter(InputArray, OutputArray, EdgePreservingMethods, Single, Single)

Filtering is the fundamental operation in image and video processing. Edge-preserving smoothing filters are used in many different applications @cite EM11 .

Declaration

public static void EdgePreservingFilter(InputArray src, OutputArray dst, EdgePreservingMethods flags = EdgePreservingMethods.RecursFilter, float sigmaS = 60F, float sigmaR = 0.4F)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
OutputArray	dst	Output 8-bit 3-channel image.
EdgePreservingMethods	flags	Edge preserving filters
System.Single	sigmaS	Range between 0 to 200.
System.Single	sigmaR	Range between 0 to 1.

Eigen(InputArray, OutputArray, OutputArray)

Computes eigenvalues and eigenvectors of a symmetric matrix.

Declaration

public static bool Eigen(InputArray src, OutputArray eigenvalues, OutputArray eigenvectors)

Parameters

Type	Name	Description
InputArray	src	The input matrix; must have CV_32FC1 or CV_64FC1 type, square size and be symmetric: src^T == src
OutputArray	eigenvalues	The output vector of eigenvalues of the same type as src; The eigenvalues are stored in the descending order.
OutputArray	eigenvectors	The output matrix of eigenvectors; It will have the same size and the same type as src; The eigenvectors are stored as subsequent matrix rows, in the same order as the corresponding eigenvalues

Returns

Type	Description
System.Boolean

EigenNonSymmetric(InputArray, OutputArray, OutputArray)

Calculates eigenvalues and eigenvectors of a non-symmetric matrix (real eigenvalues only).

Declaration

public static void EigenNonSymmetric(InputArray src, OutputArray eigenvalues, OutputArray eigenvectors)

Parameters

Type	Name	Description
InputArray	src	input matrix (CV_32FC1 or CV_64FC1 type).
OutputArray	eigenvalues	output vector of eigenvalues (type is the same type as src).
OutputArray	eigenvectors	output matrix of eigenvectors (type is the same type as src). The eigenvectors are stored as subsequent matrix rows, in the same order as the corresponding eigenvalues.

Ellipse(InputOutputArray, Point, Size, Double, Double, Double, Scalar, Int32, LineTypes, Int32)

Draws simple or thick elliptic arc or fills ellipse sector

Declaration

public static void Ellipse(InputOutputArray img, Point center, Size axes, double angle, double startAngle, double endAngle, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	Image.
OpenCvSharp.Point	center	Center of the ellipse.
OpenCvSharp.Size	axes	Length of the ellipse axes.
System.Double	angle	Rotation angle.
System.Double	startAngle	Starting angle of the elliptic arc.
System.Double	endAngle	Ending angle of the elliptic arc.
OpenCvSharp.Scalar	color	Ellipse color.
System.Int32	thickness	Thickness of the ellipse arc. [By default this is 1]
LineTypes	lineType	Type of the ellipse boundary. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the center coordinates and axes' values. [By default this is 0]

Ellipse(InputOutputArray, RotatedRect, Scalar, Int32, LineTypes)

Draws simple or thick elliptic arc or fills ellipse sector

Declaration

public static void Ellipse(InputOutputArray img, RotatedRect box, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8)

Parameters

Type	Name	Description
InputOutputArray	img	Image.
OpenCvSharp.RotatedRect	box	The enclosing box of the ellipse drawn
OpenCvSharp.Scalar	color	Ellipse color.
System.Int32	thickness	Thickness of the ellipse boundary. [By default this is 1]
LineTypes	lineType	Type of the ellipse boundary. [By default this is LineType.Link8]

Ellipse2Poly(Point, Size, Int32, Int32, Int32, Int32)

Approximates an elliptic arc with a polyline. The function ellipse2Poly computes the vertices of a polyline that approximates the specified elliptic arc. It is used by cv::ellipse.

Declaration

public static Point[] Ellipse2Poly(Point center, Size axes, int angle, int arcStart, int arcEnd, int delta)

Parameters

Type	Name	Description
OpenCvSharp.Point	center	Center of the arc.
OpenCvSharp.Size	axes	Half of the size of the ellipse main axes. See the ellipse for details.
System.Int32	angle	Rotation angle of the ellipse in degrees. See the ellipse for details.
System.Int32	arcStart	Starting angle of the elliptic arc in degrees.
System.Int32	arcEnd	Ending angle of the elliptic arc in degrees.
System.Int32	delta	Angle between the subsequent polyline vertices. It defines the approximation

Returns

Type	Description
OpenCvSharp.Point[]	Output vector of polyline vertices.

Ellipse2Poly(Point2d, Size2d, Int32, Int32, Int32, Int32)

Approximates an elliptic arc with a polyline. The function ellipse2Poly computes the vertices of a polyline that approximates the specified elliptic arc. It is used by cv::ellipse.

Declaration

public static Point2d[] Ellipse2Poly(Point2d center, Size2d axes, int angle, int arcStart, int arcEnd, int delta)

Parameters

Type	Name	Description
OpenCvSharp.Point2d	center	Center of the arc.
OpenCvSharp.Size2d	axes	Half of the size of the ellipse main axes. See the ellipse for details.
System.Int32	angle	Rotation angle of the ellipse in degrees. See the ellipse for details.
System.Int32	arcStart	Starting angle of the elliptic arc in degrees.
System.Int32	arcEnd	Ending angle of the elliptic arc in degrees.
System.Int32	delta	Angle between the subsequent polyline vertices. It defines the approximation

Returns

Type	Description
OpenCvSharp.Point2d[]	Output vector of polyline vertices.

EMD(InputArray, InputArray, DistanceTypes)

Computes the "minimal work" distance between two weighted point configurations.

The function computes the earth mover distance and/or a lower boundary of the distance between the two weighted point configurations.One of the applications described in @cite RubnerSept98, @cite Rubner2000 is multi-dimensional histogram comparison for image retrieval.EMD is a transportation problem that is solved using some modification of a simplex algorithm, thus the complexity is exponential in the worst case, though, on average it is much faster.In the case of a real metric the lower boundary can be calculated even faster (using linear-time algorithm) and it can be used to determine roughly whether the two signatures are far enough so that they cannot relate to the same object.

Declaration

public static float EMD(InputArray signature1, InputArray signature2, DistanceTypes distType)

Parameters

Type	Name	Description
InputArray	signature1	First signature, a \f$\texttt{size1}\times \texttt{dims}+1\f$ floating-point matrix. Each row stores the point weight followed by the point coordinates.The matrix is allowed to have a single column(weights only) if the user-defined cost matrix is used.The weights must be non-negative and have at least one non-zero value.
InputArray	signature2	Second signature of the same format as signature1 , though the number of rows may be different.The total weights may be different.In this case an extra "dummy" point is added to either signature1 or signature2. The weights must be non-negative and have at least one non-zero value.
DistanceTypes	distType	Used metric.

Returns

Type	Description
System.Single

EMD(InputArray, InputArray, DistanceTypes, InputArray)

Computes the "minimal work" distance between two weighted point configurations.

The function computes the earth mover distance and/or a lower boundary of the distance between the two weighted point configurations.One of the applications described in @cite RubnerSept98, @cite Rubner2000 is multi-dimensional histogram comparison for image retrieval.EMD is a transportation problem that is solved using some modification of a simplex algorithm, thus the complexity is exponential in the worst case, though, on average it is much faster.In the case of a real metric the lower boundary can be calculated even faster (using linear-time algorithm) and it can be used to determine roughly whether the two signatures are far enough so that they cannot relate to the same object.

Declaration

public static float EMD(InputArray signature1, InputArray signature2, DistanceTypes distType, InputArray cost)

Parameters

Type	Name	Description
InputArray	signature1	First signature, a \f$\texttt{size1}\times \texttt{dims}+1\f$ floating-point matrix. Each row stores the point weight followed by the point coordinates.The matrix is allowed to have a single column(weights only) if the user-defined cost matrix is used.The weights must be non-negative and have at least one non-zero value.
InputArray	signature2	Second signature of the same format as signature1 , though the number of rows may be different.The total weights may be different.In this case an extra "dummy" point is added to either signature1 or signature2. The weights must be non-negative and have at least one non-zero value.
DistanceTypes	distType	Used metric.
InputArray	cost	User-defined size1 x size2 cost matrix. Also, if a cost matrix is used, lower boundary lowerBound cannot be calculated because it needs a metric function.

Returns

Type	Description
System.Single

EMD(InputArray, InputArray, DistanceTypes, InputArray, out Single, OutputArray)

Computes the "minimal work" distance between two weighted point configurations.

The function computes the earth mover distance and/or a lower boundary of the distance between the two weighted point configurations.One of the applications described in @cite RubnerSept98, @cite Rubner2000 is multi-dimensional histogram comparison for image retrieval.EMD is a transportation problem that is solved using some modification of a simplex algorithm, thus the complexity is exponential in the worst case, though, on average it is much faster.In the case of a real metric the lower boundary can be calculated even faster (using linear-time algorithm) and it can be used to determine roughly whether the two signatures are far enough so that they cannot relate to the same object.

Declaration

public static float EMD(InputArray signature1, InputArray signature2, DistanceTypes distType, InputArray cost, out float lowerBound, OutputArray flow = null)

Parameters

Type	Name	Description
InputArray	signature1	First signature, a \f$\texttt{size1}\times \texttt{dims}+1\f$ floating-point matrix. Each row stores the point weight followed by the point coordinates.The matrix is allowed to have a single column(weights only) if the user-defined cost matrix is used.The weights must be non-negative and have at least one non-zero value.
InputArray	signature2	Second signature of the same format as signature1 , though the number of rows may be different.The total weights may be different.In this case an extra "dummy" point is added to either signature1 or signature2. The weights must be non-negative and have at least one non-zero value.
DistanceTypes	distType	Used metric.
InputArray	cost	User-defined size1 x size2 cost matrix. Also, if a cost matrix is used, lower boundary lowerBound cannot be calculated because it needs a metric function.
System.Single	lowerBound	Optional input/output parameter: lower boundary of a distance between the two signatures that is a distance between mass centers.The lower boundary may not be calculated if the user-defined cost matrix is used, the total weights of point configurations are not equal, or if the signatures consist of weights only(the signature matrices have a single column). You ** must** initialize *lowerBound.If the calculated distance between mass centers is greater or equal to *lowerBound(it means that the signatures are far enough), the function does not calculate EMD. In any case *lowerBound is set to the calculated distance between mass centers on return. Thus, if you want to calculate both distance between mass centers and EMD, *lowerBound should be set to 0.
OutputArray	flow	Resultant size1 x size2 flow matrix: flow[i,j] is a flow from i-th point of signature1 to j-th point of signature2.

Returns

Type	Description
System.Single

EqualizeHist(InputArray, OutputArray)

normalizes the grayscale image brightness and contrast by normalizing its histogram

Declaration

public static void EqualizeHist(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	The source 8-bit single channel image
OutputArray	dst	The destination image; will have the same size and the same type as src

Erode(InputArray, OutputArray, InputArray, Nullable<Point>, Int32, BorderTypes, Nullable<Scalar>)

Erodes an image by using a specific structuring element.

Declaration

public static void Erode(InputArray src, OutputArray dst, InputArray element, Point? anchor = null, int iterations = 1, BorderTypes borderType = BorderTypes.Constant, Scalar? borderValue = null)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image. It will have the same size and the same type as src
InputArray	element	The structuring element used for dilation. If element=new Mat(), a 3x3 rectangular structuring element is used
System.Nullable<OpenCvSharp.Point>	anchor	Position of the anchor within the element. The default value (-1, -1) means that the anchor is at the element center
System.Int32	iterations	The number of times erosion is applied
BorderTypes	borderType	The pixel extrapolation method
System.Nullable<OpenCvSharp.Scalar>	borderValue	The border value in case of a constant border. The default value has a special meaning. [By default this is CvCpp.MorphologyDefaultBorderValue()]

EstimateAffine2D(InputArray, InputArray, OutputArray, RobustEstimationAlgorithms, Double, UInt64, Double, UInt64)

Computes an optimal affine transformation between two 2D point sets.

Declaration

public static Mat EstimateAffine2D(InputArray from, InputArray to, OutputArray inliers = null, RobustEstimationAlgorithms method = RobustEstimationAlgorithms.RANSAC, double ransacReprojThreshold = 3, ulong maxIters = 2000UL, double confidence = 0.99, ulong refineIters = 10UL)

Parameters

Type	Name	Description
InputArray	from	First input 2D point set containing (X,Y).
InputArray	to	Second input 2D point set containing (x,y).
OutputArray	inliers	Output vector indicating which points are inliers (1-inlier, 0-outlier).
RobustEstimationAlgorithms	method	Robust method used to compute transformation.
System.Double	ransacReprojThreshold	Maximum reprojection error in the RANSAC algorithm to consider a point as an inlier.Applies only to RANSAC.
System.UInt64	maxIters	The maximum number of robust method iterations.
System.Double	confidence	Confidence level, between 0 and 1, for the estimated transformation. Anything between 0.95 and 0.99 is usually good enough.Values too close to 1 can slow down the estimation significantly.Values lower than 0.8-0.9 can result in an incorrectly estimated transformation.
System.UInt64	refineIters	Maximum number of iterations of refining algorithm (Levenberg-Marquardt). Passing 0 will disable refining, so the output matrix will be output of robust method.

Returns

Type	Description
Mat	Output 2D affine transformation matrix \f$2 \times 3\f$ or empty matrix if transformation could not be estimated.

EstimateAffine3D(InputArray, InputArray, OutputArray, OutputArray, Double, Double)

Computes an optimal affine transformation between two 3D point sets.

Declaration

public static int EstimateAffine3D(InputArray src, InputArray dst, OutputArray outVal, OutputArray inliers, double ransacThreshold = 3, double confidence = 0.99)

Parameters

Type	Name	Description
InputArray	src	First input 3D point set.
InputArray	dst	Second input 3D point set.
OutputArray	outVal	Output 3D affine transformation matrix 3 x 4 .
OutputArray	inliers	Output vector indicating which points are inliers.
System.Double	ransacThreshold	Maximum reprojection error in the RANSAC algorithm to consider a point as an inlier.
System.Double	confidence	Confidence level, between 0 and 1, for the estimated transformation. Anything between 0.95 and 0.99 is usually good enough. Values too close to 1 can slow down the estimation significantly. Values lower than 0.8-0.9 can result in an incorrectly estimated transformation.

Returns

Type	Description
System.Int32

EstimateAffinePartial2D(InputArray, InputArray, OutputArray, RobustEstimationAlgorithms, Double, UInt64, Double, UInt64)

Computes an optimal limited affine transformation with 4 degrees of freedom between two 2D point sets.

Declaration

public static Mat EstimateAffinePartial2D(InputArray from, InputArray to, OutputArray inliers = null, RobustEstimationAlgorithms method = RobustEstimationAlgorithms.RANSAC, double ransacReprojThreshold = 3, ulong maxIters = 2000UL, double confidence = 0.99, ulong refineIters = 10UL)

Parameters

Type	Name	Description
InputArray	from	First input 2D point set.
InputArray	to	Second input 2D point set.
OutputArray	inliers	Output vector indicating which points are inliers.
RobustEstimationAlgorithms	method	Robust method used to compute transformation.
System.Double	ransacReprojThreshold	Maximum reprojection error in the RANSAC algorithm to consider a point as an inlier.Applies only to RANSAC.
System.UInt64	maxIters	The maximum number of robust method iterations.
System.Double	confidence	Confidence level, between 0 and 1, for the estimated transformation. Anything between 0.95 and 0.99 is usually good enough.Values too close to 1 can slow down the estimation significantly.Values lower than 0.8-0.9 can result in an incorrectly estimated transformation.
System.UInt64	refineIters

Returns

Type	Description
Mat	Output 2D affine transformation (4 degrees of freedom) matrix 2x3 or empty matrix if transformation could not be estimated.

EvaluateFeatureDetector(Mat, Mat, Mat, ref KeyPoint[], ref KeyPoint[], out Single, out Int32)

Declaration

public static void EvaluateFeatureDetector(Mat img1, Mat img2, Mat H1to2, ref KeyPoint[] keypoints1, ref KeyPoint[] keypoints2, out float repeatability, out int correspCount)

Parameters

Type	Name	Description
Mat	img1
Mat	img2
Mat	H1to2
OpenCvSharp.KeyPoint[]	keypoints1
OpenCvSharp.KeyPoint[]	keypoints2
System.Single	repeatability
System.Int32	correspCount

Exp(InputArray, OutputArray)

computes exponent of each matrix element (dst = e**src)

Declaration

public static void Exp(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	The source array
OutputArray	dst	The destination array; will have the same size and same type as src

ExtractChannel(InputArray, OutputArray, Int32)

extracts a single channel from src (coi is 0-based index)

Declaration

public static void ExtractChannel(InputArray src, OutputArray dst, int coi)

Parameters

Type	Name	Description
InputArray	src
OutputArray	dst
System.Int32	coi

FAST(InputArray, Int32, Boolean)

Detects corners using the FAST algorithm

Declaration

public static KeyPoint[] FAST(InputArray image, int threshold, bool nonmaxSupression = true)

Parameters

Type	Name	Description
InputArray	image	grayscale image where keypoints (corners) are detected.
System.Int32	threshold	threshold on difference between intensity of the central pixel and pixels of a circle around this pixel.
System.Boolean	nonmaxSupression	if true, non-maximum suppression is applied to detected corners (keypoints).

Returns

Type	Description
OpenCvSharp.KeyPoint[]	keypoints detected on the image.

FAST(InputArray, Int32, Boolean, FASTType)

Detects corners using the FAST algorithm

Declaration

public static KeyPoint[] FAST(InputArray image, int threshold, bool nonmaxSupression, FASTType type)

Parameters

Type	Name	Description
InputArray	image	grayscale image where keypoints (corners) are detected.
System.Int32	threshold	threshold on difference between intensity of the central pixel and pixels of a circle around this pixel.
System.Boolean	nonmaxSupression	if true, non-maximum suppression is applied to detected corners (keypoints).
FASTType	type	one of the three neighborhoods as defined in the paper

Returns

Type	Description
OpenCvSharp.KeyPoint[]	keypoints detected on the image.

FastAtan2(Single, Single)

computes the angle in degrees (0..360) of the vector (x,y)

Declaration

public static float FastAtan2(float y, float x)

Parameters

Type	Name	Description
System.Single	y
System.Single	x

Returns

Type	Description
System.Single

FastNlMeansDenoising(InputArray, OutputArray, Single, Int32, Int32)

Perform image denoising using Non-local Means Denoising algorithm with several computational optimizations. Noise expected to be a gaussian white noise

Declaration

public static void FastNlMeansDenoising(InputArray src, OutputArray dst, float h = 3F, int templateWindowSize = 7, int searchWindowSize = 21)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 1-channel, 2-channel or 3-channel image.
OutputArray	dst	Output image with the same size and type as src .
System.Single	h	Parameter regulating filter strength. Big h value perfectly removes noise but also removes image details, smaller h value preserves details but also preserves some noise
System.Int32	templateWindowSize	Size in pixels of the template patch that is used to compute weights. Should be odd. Recommended value 7 pixels
System.Int32	searchWindowSize	Size in pixels of the window that is used to compute weighted average for given pixel. Should be odd. Affect performance linearly: greater searchWindowsSize - greater denoising time. Recommended value 21 pixels

FastNlMeansDenoisingColored(InputArray, OutputArray, Single, Single, Int32, Int32)

Modification of fastNlMeansDenoising function for colored images

Declaration

public static void FastNlMeansDenoisingColored(InputArray src, OutputArray dst, float h = 3F, float hColor = 3F, int templateWindowSize = 7, int searchWindowSize = 21)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
OutputArray	dst	Output image with the same size and type as src.
System.Single	h	Parameter regulating filter strength for luminance component. Bigger h value perfectly removes noise but also removes image details, smaller h value preserves details but also preserves some noise
System.Single	hColor	The same as h but for color components. For most images value equals 10 will be enought to remove colored noise and do not distort colors
System.Int32	templateWindowSize	Size in pixels of the template patch that is used to compute weights. Should be odd. Recommended value 7 pixels
System.Int32	searchWindowSize	Size in pixels of the window that is used to compute weighted average for given pixel. Should be odd. Affect performance linearly: greater searchWindowsSize - greater denoising time. Recommended value 21 pixels

FastNlMeansDenoisingColoredMulti(IEnumerable<Mat>, OutputArray, Int32, Int32, Single, Single, Int32, Int32)

Modification of fastNlMeansDenoisingMulti function for colored images sequences

Declaration

public static void FastNlMeansDenoisingColoredMulti(IEnumerable<Mat> srcImgs, OutputArray dst, int imgToDenoiseIndex, int temporalWindowSize, float h = 3F, float hColor = 3F, int templateWindowSize = 7, int searchWindowSize = 21)

Parameters

Type	Name	Description
IEnumerable<Mat>	srcImgs	Input 8-bit 3-channel images sequence. All images should have the same type and size.
OutputArray	dst	Output image with the same size and type as srcImgs images.
System.Int32	imgToDenoiseIndex	Target image to denoise index in srcImgs sequence
System.Int32	temporalWindowSize	Number of surrounding images to use for target image denoising. Should be odd. Images from imgToDenoiseIndex - temporalWindowSize / 2 to imgToDenoiseIndex - temporalWindowSize / 2 from srcImgs will be used to denoise srcImgs[imgToDenoiseIndex] image.
System.Single	h	Parameter regulating filter strength for luminance component. Bigger h value perfectly removes noise but also removes image details, smaller h value preserves details but also preserves some noise.
System.Single	hColor	The same as h but for color components.
System.Int32	templateWindowSize	Size in pixels of the template patch that is used to compute weights. Should be odd. Recommended value 7 pixels
System.Int32	searchWindowSize	Size in pixels of the window that is used to compute weighted average for given pixel. Should be odd. Affect performance linearly: greater searchWindowsSize - greater denoising time. Recommended value 21 pixels

FastNlMeansDenoisingMulti(IEnumerable<Mat>, OutputArray, Int32, Int32, Single, Int32, Int32)

Modification of fastNlMeansDenoising function for images sequence where consequtive images have been captured in small period of time. For example video. This version of the function is for grayscale images or for manual manipulation with colorspaces.

Declaration

public static void FastNlMeansDenoisingMulti(IEnumerable<Mat> srcImgs, OutputArray dst, int imgToDenoiseIndex, int temporalWindowSize, float h = 3F, int templateWindowSize = 7, int searchWindowSize = 21)

Parameters

Type	Name	Description
IEnumerable<Mat>	srcImgs	Input 8-bit 1-channel, 2-channel or 3-channel images sequence. All images should have the same type and size.
OutputArray	dst	Output image with the same size and type as srcImgs images.
System.Int32	imgToDenoiseIndex	Target image to denoise index in srcImgs sequence
System.Int32	temporalWindowSize	Number of surrounding images to use for target image denoising. Should be odd. Images from imgToDenoiseIndex - temporalWindowSize / 2 to imgToDenoiseIndex - temporalWindowSize / 2 from srcImgs will be used to denoise srcImgs[imgToDenoiseIndex] image.
System.Single	h	Parameter regulating filter strength for luminance component. Bigger h value perfectly removes noise but also removes image details, smaller h value preserves details but also preserves some noise
System.Int32	templateWindowSize	Size in pixels of the template patch that is used to compute weights. Should be odd. Recommended value 7 pixels
System.Int32	searchWindowSize	Size in pixels of the window that is used to compute weighted average for given pixel. Should be odd. Affect performance linearly: greater searchWindowsSize - greater denoising time. Recommended value 21 pixels

FillConvexPoly(InputOutputArray, InputArray, Scalar, LineTypes, Int32)

Fills a convex polygon.

Declaration

public static void FillConvexPoly(InputOutputArray img, InputArray pts, Scalar color, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	Image
InputArray	pts	The polygon vertices
OpenCvSharp.Scalar	color	Polygon color
LineTypes	lineType	Type of the polygon boundaries
System.Int32	shift	The number of fractional bits in the vertex coordinates

FillConvexPoly(Mat, IEnumerable<Point>, Scalar, LineTypes, Int32)

Fills a convex polygon.

Declaration

public static void FillConvexPoly(Mat img, IEnumerable<Point> pts, Scalar color, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
Mat	img	Image
IEnumerable<OpenCvSharp.Point>	pts	The polygon vertices
OpenCvSharp.Scalar	color	Polygon color
LineTypes	lineType	Type of the polygon boundaries
System.Int32	shift	The number of fractional bits in the vertex coordinates

FillPoly(InputOutputArray, InputArray, Scalar, LineTypes, Int32, Nullable<Point>)

Fills the area bounded by one or more polygons

Declaration

public static void FillPoly(InputOutputArray img, InputArray pts, Scalar color, LineTypes lineType = LineTypes.Link8, int shift = 0, Point? offset = null)

Parameters

Type	Name	Description
InputOutputArray	img	Image
InputArray	pts	Array of polygons, each represented as an array of points
OpenCvSharp.Scalar	color	Polygon color
LineTypes	lineType	Type of the polygon boundaries
System.Int32	shift	The number of fractional bits in the vertex coordinates
System.Nullable<OpenCvSharp.Point>	offset

FillPoly(Mat, IEnumerable<IEnumerable<Point>>, Scalar, LineTypes, Int32, Nullable<Point>)

Fills the area bounded by one or more polygons

Declaration

public static void FillPoly(Mat img, IEnumerable<IEnumerable<Point>> pts, Scalar color, LineTypes lineType = LineTypes.Link8, int shift = 0, Point? offset = null)

Parameters

Type	Name	Description
Mat	img	Image
IEnumerable<IEnumerable<OpenCvSharp.Point>>	pts	Array of polygons, each represented as an array of points
OpenCvSharp.Scalar	color	Polygon color
LineTypes	lineType	Type of the polygon boundaries
System.Int32	shift	The number of fractional bits in the vertex coordinates
System.Nullable<OpenCvSharp.Point>	offset

Filter2D(InputArray, OutputArray, MatType, InputArray, Nullable<Point>, Double, BorderTypes)

Convolves an image with the kernel

Declaration

public static void Filter2D(InputArray src, OutputArray dst, MatType ddepth, InputArray kernel, Point? anchor = null, double delta = 0, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image. It will have the same size and the same number of channels as src
OpenCvSharp.MatType	ddepth	The desired depth of the destination image. If it is negative, it will be the same as src.depth()
InputArray	kernel	Convolution kernel (or rather a correlation kernel), a single-channel floating point matrix. If you want to apply different kernels to different channels, split the image into separate color planes using split() and process them individually
System.Nullable<OpenCvSharp.Point>	anchor	The anchor of the kernel that indicates the relative position of a filtered point within the kernel. The anchor should lie within the kernel. The special default value (-1,-1) means that the anchor is at the kernel center
System.Double	delta	The optional value added to the filtered pixels before storing them in dst
BorderTypes	borderType	The pixel extrapolation method

FilterHomographyDecompByVisibleRefpoints(IEnumerable<Mat>, IEnumerable<Mat>, InputArray, InputArray, OutputArray, InputArray)

Filters homography decompositions based on additional information.

Declaration

public static void FilterHomographyDecompByVisibleRefpoints(IEnumerable<Mat> rotations, IEnumerable<Mat> normals, InputArray beforePoints, InputArray afterPoints, OutputArray possibleSolutions, InputArray pointsMask = null)

Parameters

Type	Name	Description
IEnumerable<Mat>	rotations	Vector of rotation matrices.
IEnumerable<Mat>	normals	Vector of plane normal matrices.
InputArray	beforePoints	Vector of (rectified) visible reference points before the homography is applied
InputArray	afterPoints	Vector of (rectified) visible reference points after the homography is applied
OutputArray	possibleSolutions	Vector of int indices representing the viable solution set after filtering
InputArray	pointsMask	optional Mat/Vector of 8u type representing the mask for the inliers as given by the findHomography function

FilterSpeckles(InputOutputArray, Double, Int32, Double, InputOutputArray)

filters off speckles (small regions of incorrectly computed disparity)

Declaration

public static void FilterSpeckles(InputOutputArray img, double newVal, int maxSpeckleSize, double maxDiff, InputOutputArray buf = null)

Parameters

Type	Name	Description
InputOutputArray	img	The input 16-bit signed disparity image
System.Double	newVal	The disparity value used to paint-off the speckles
System.Int32	maxSpeckleSize	The maximum speckle size to consider it a speckle. Larger blobs are not affected by the algorithm
System.Double	maxDiff	Maximum difference between neighbor disparity pixels to put them into the same blob. Note that since StereoBM, StereoSGBM and may be other algorithms return a fixed-point disparity map, where disparity values are multiplied by 16, this scale factor should be taken into account when specifying this parameter value.
InputOutputArray	buf	The optional temporary buffer to avoid memory allocation within the function.

Find4QuadCornerSubpix(InputArray, InputOutputArray, Size)

finds subpixel-accurate positions of the chessboard corners

Declaration

public static bool Find4QuadCornerSubpix(InputArray img, InputOutputArray corners, Size regionSize)

Parameters

Type	Name	Description
InputArray	img
InputOutputArray	corners
OpenCvSharp.Size	regionSize

Returns

Type	Description
System.Boolean

Find4QuadCornerSubpix(InputArray, Point2f[], Size)

finds subpixel-accurate positions of the chessboard corners

Declaration

public static bool Find4QuadCornerSubpix(InputArray img, Point2f[] corners, Size regionSize)

Parameters

Type	Name	Description
InputArray	img
OpenCvSharp.Point2f[]	corners
OpenCvSharp.Size	regionSize

Returns

Type	Description
System.Boolean

FindChessboardCorners(InputArray, Size, OutputArray, ChessboardFlags)

Finds the positions of internal corners of the chessboard.

Declaration

public static bool FindChessboardCorners(InputArray image, Size patternSize, OutputArray corners, ChessboardFlags flags = (ChessboardFlags)3)

Parameters

Type	Name	Description
InputArray	image	Source chessboard view. It must be an 8-bit grayscale or color image.
OpenCvSharp.Size	patternSize	Number of inner corners per a chessboard row and column ( patternSize = Size(points_per_row,points_per_colum) = Size(columns, rows) ).
OutputArray	corners	Output array of detected corners.
ChessboardFlags	flags	Various operation flags that can be zero or a combination of the ChessboardFlag values

Returns

Type	Description
System.Boolean	The function returns true if all of the corners are found and they are placed in a certain order (row by row, left to right in every row). Otherwise, if the function fails to find all the corners or reorder them, it returns false.

FindChessboardCorners(InputArray, Size, out Point2f[], ChessboardFlags)

Finds the positions of internal corners of the chessboard.

Declaration

public static bool FindChessboardCorners(InputArray image, Size patternSize, out Point2f[] corners, ChessboardFlags flags = (ChessboardFlags)3)

Parameters

Type	Name	Description
InputArray	image	Source chessboard view. It must be an 8-bit grayscale or color image.
OpenCvSharp.Size	patternSize	Number of inner corners per a chessboard row and column ( patternSize = Size(points_per_row,points_per_colum) = Size(columns, rows) ).
OpenCvSharp.Point2f[]	corners	Output array of detected corners.
ChessboardFlags	flags	Various operation flags that can be zero or a combination of the ChessboardFlag values

Returns

Type	Description
System.Boolean	The function returns true if all of the corners are found and they are placed in a certain order (row by row, left to right in every row). Otherwise, if the function fails to find all the corners or reorder them, it returns false.

FindChessboardCornersSB(InputArray, Size, OutputArray, ChessboardFlags)

Finds the positions of internal corners of the chessboard using a sector based approach.

Declaration

public static bool FindChessboardCornersSB(InputArray image, Size patternSize, OutputArray corners, ChessboardFlags flags = ChessboardFlags.None)

Parameters

Type	Name	Description
InputArray	image	image Source chessboard view. It must be an 8-bit grayscale or color image.
OpenCvSharp.Size	patternSize	Number of inner corners per a chessboard row and column (patternSize = Size(points_per_row, points_per_column) = Size(columns, rows) ).
OutputArray	corners	Output array of detected corners.
ChessboardFlags	flags	flags Various operation flags that can be zero or a combination of the ChessboardFlags values.

Returns

Type	Description
System.Boolean

FindChessboardCornersSB(InputArray, Size, out Point2f[], ChessboardFlags)

Finds the positions of internal corners of the chessboard using a sector based approach.

Declaration

public static bool FindChessboardCornersSB(InputArray image, Size patternSize, out Point2f[] corners, ChessboardFlags flags = ChessboardFlags.None)

Parameters

Type	Name	Description
InputArray	image	image Source chessboard view. It must be an 8-bit grayscale or color image.
OpenCvSharp.Size	patternSize	Number of inner corners per a chessboard row and column (patternSize = Size(points_per_row, points_per_column) = Size(columns, rows) ).
OpenCvSharp.Point2f[]	corners	Output array of detected corners.
ChessboardFlags	flags	flags Various operation flags that can be zero or a combination of the ChessboardFlags values.

Returns

Type	Description
System.Boolean

FindCirclesGrid(InputArray, Size, OutputArray, FindCirclesGridFlags, Feature2D)

Finds centers in the grid of circles.

Declaration

public static bool FindCirclesGrid(InputArray image, Size patternSize, OutputArray centers, FindCirclesGridFlags flags = FindCirclesGridFlags.SymmetricGrid, Feature2D blobDetector = null)

Parameters

Type	Name	Description
InputArray	image	grid view of input circles; it must be an 8-bit grayscale or color image.
OpenCvSharp.Size	patternSize	number of circles per row and column ( patternSize = Size(points_per_row, points_per_colum) ).
OutputArray	centers	output array of detected centers.
FindCirclesGridFlags	flags	various operation flags that can be one of the FindCirclesGridFlag values
Feature2D	blobDetector	feature detector that finds blobs like dark circles on light background.

Returns

Type	Description
System.Boolean

FindCirclesGrid(InputArray, Size, out Point2f[], FindCirclesGridFlags, Feature2D)

Finds centers in the grid of circles.

Declaration

public static bool FindCirclesGrid(InputArray image, Size patternSize, out Point2f[] centers, FindCirclesGridFlags flags = FindCirclesGridFlags.SymmetricGrid, Feature2D blobDetector = null)

Parameters

Type	Name	Description
InputArray	image	grid view of input circles; it must be an 8-bit grayscale or color image.
OpenCvSharp.Size	patternSize	number of circles per row and column ( patternSize = Size(points_per_row, points_per_colum) ).
OpenCvSharp.Point2f[]	centers	output array of detected centers.
FindCirclesGridFlags	flags	various operation flags that can be one of the FindCirclesGridFlag values
Feature2D	blobDetector	feature detector that finds blobs like dark circles on light background.

Returns

Type	Description
System.Boolean

FindContours(InputArray, out Mat[], OutputArray, RetrievalModes, ContourApproximationModes, Nullable<Point>)

Finds contours in a binary image.

Declaration

public static void FindContours(InputArray image, out Mat[] contours, OutputArray hierarchy, RetrievalModes mode, ContourApproximationModes method, Point? offset = null)

Parameters

Type	Name	Description
InputArray	image	Source, an 8-bit single-channel image. Non-zero pixels are treated as 1’s. Zero pixels remain 0’s, so the image is treated as binary. The function modifies the image while extracting the contours.
Mat[]	contours	Detected contours. Each contour is stored as a vector of points.
OutputArray	hierarchy	Optional output vector, containing information about the image topology. It has as many elements as the number of contours. For each i-th contour contours[i], the members of the elements hierarchy[i] are set to 0-based indices in contours of the next and previous contours at the same hierarchical level, the first child contour and the parent contour, respectively. If for the contour i there are no next, previous, parent, or nested contours, the corresponding elements of hierarchy[i] will be negative.
RetrievalModes	mode	Contour retrieval mode
ContourApproximationModes	method	Contour approximation method
System.Nullable<OpenCvSharp.Point>	offset	Optional offset by which every contour point is shifted. This is useful if the contours are extracted from the image ROI and then they should be analyzed in the whole image context.

FindContours(InputArray, out Point[][], out HierarchyIndex[], RetrievalModes, ContourApproximationModes, Nullable<Point>)

Finds contours in a binary image.

Declaration

public static void FindContours(InputArray image, out Point[][] contours, out HierarchyIndex[] hierarchy, RetrievalModes mode, ContourApproximationModes method, Point? offset = null)

Parameters

Type	Name	Description
InputArray	image	Source, an 8-bit single-channel image. Non-zero pixels are treated as 1’s. Zero pixels remain 0’s, so the image is treated as binary. The function modifies the image while extracting the contours.
OpenCvSharp.Point[][]	contours	Detected contours. Each contour is stored as a vector of points.
HierarchyIndex[]	hierarchy	Optional output vector, containing information about the image topology. It has as many elements as the number of contours. For each i-th contour contours[i], the members of the elements hierarchy[i] are set to 0-based indices in contours of the next and previous contours at the same hierarchical level, the first child contour and the parent contour, respectively. If for the contour i there are no next, previous, parent, or nested contours, the corresponding elements of hierarchy[i] will be negative.
RetrievalModes	mode	Contour retrieval mode
ContourApproximationModes	method	Contour approximation method
System.Nullable<OpenCvSharp.Point>	offset	Optional offset by which every contour point is shifted. This is useful if the contours are extracted from the image ROI and then they should be analyzed in the whole image context.

FindContoursAsArray(InputArray, RetrievalModes, ContourApproximationModes, Nullable<Point>)

Finds contours in a binary image.

Declaration

public static Point[][] FindContoursAsArray(InputArray image, RetrievalModes mode, ContourApproximationModes method, Point? offset = null)

Parameters

Type	Name	Description
InputArray	image	Source, an 8-bit single-channel image. Non-zero pixels are treated as 1’s. Zero pixels remain 0’s, so the image is treated as binary. The function modifies the image while extracting the contours.
RetrievalModes	mode	Contour retrieval mode
ContourApproximationModes	method	Contour approximation method
System.Nullable<OpenCvSharp.Point>	offset	Optional offset by which every contour point is shifted. This is useful if the contours are extracted from the image ROI and then they should be analyzed in the whole image context.

Returns

Type	Description
OpenCvSharp.Point[][]	Detected contours. Each contour is stored as a vector of points.

FindContoursAsMat(InputArray, RetrievalModes, ContourApproximationModes, Nullable<Point>)

Finds contours in a binary image.

Declaration

public static Mat<Point>[] FindContoursAsMat(InputArray image, RetrievalModes mode, ContourApproximationModes method, Point? offset = null)

Parameters

Type	Name	Description
InputArray	image	Source, an 8-bit single-channel image. Non-zero pixels are treated as 1’s. Zero pixels remain 0’s, so the image is treated as binary. The function modifies the image while extracting the contours.
RetrievalModes	mode	Contour retrieval mode
ContourApproximationModes	method	Contour approximation method
System.Nullable<OpenCvSharp.Point>	offset	Optional offset by which every contour point is shifted. This is useful if the contours are extracted from the image ROI and then they should be analyzed in the whole image context.

Returns

Type	Description
Mat<OpenCvSharp.Point>[]	Detected contours. Each contour is stored as a vector of points.

FindEssentialMat(InputArray, InputArray, InputArray, EssentialMatMethod, Double, Double, OutputArray)

Calculates an essential matrix from the corresponding points in two images.

Declaration

public static Mat FindEssentialMat(InputArray points1, InputArray points2, InputArray cameraMatrix, EssentialMatMethod method = EssentialMatMethod.Ransac, double prob = 0.999, double threshold = 1, OutputArray mask = null)

Parameters

Type	Name	Description
InputArray	points1	Array of N (N >= 5) 2D points from the first image. The point coordinates should be floating-point (single or double precision).
InputArray	points2	Array of the second image points of the same size and format as points1 .
InputArray	cameraMatrix	Camera matrix K=⎡⎣⎢fx000fy0cxcy1⎤⎦⎥ . Note that this function assumes that points1 and points2 are feature points from cameras with the same camera matrix.
EssentialMatMethod	method	Method for computing an essential matrix. RANSAC for the RANSAC algorithm. LMEDS for the LMedS algorithm.
System.Double	prob	Parameter used for the RANSAC or LMedS methods only. It specifies a desirable level of confidence (probability) that the estimated matrix is correct.
System.Double	threshold	Parameter used for RANSAC. It is the maximum distance from a point to an epipolar line in pixels, beyond which the point is considered an outlier and is not used for computing the final fundamental matrix. It can be set to something like 1-3, depending on the accuracy of the point localization, image resolution, and the image noise.
OutputArray	mask	Output array of N elements, every element of which is set to 0 for outliers and to 1 for the other points. The array is computed only in the RANSAC and LMedS methods.

Returns

Type	Description
Mat	essential matrix

FindEssentialMat(InputArray, InputArray, Double, Point2d, EssentialMatMethod, Double, Double, OutputArray)

Calculates an essential matrix from the corresponding points in two images.

Declaration

public static Mat FindEssentialMat(InputArray points1, InputArray points2, double focal, Point2d pp, EssentialMatMethod method = EssentialMatMethod.Ransac, double prob = 0.999, double threshold = 1, OutputArray mask = null)

Parameters

Type	Name	Description
InputArray	points1	Array of N (N >= 5) 2D points from the first image. The point coordinates should be floating-point (single or double precision).
InputArray	points2	Array of the second image por LMedS methods only. It specifies a desirable level of confidence (probability) that the estimated matrix is correct.
System.Double	focal	Focal length of the camera. Note that this function assumes that points1 and points2 are feature points from cameras with same focal length and principal point.
OpenCvSharp.Point2d	pp	principal point of the camera.
EssentialMatMethod	method	Method for computing an essential matrix. RANSAC for the RANSAC algorithm. LMEDS for the LMedS algorithm.
System.Double	prob	Parameter used for the RANSAC othe accuracy of the point localization, image resolution, and the image noise.
System.Double	threshold	Parameter used for RANSAC. It is the maximum distance from a point to an epipolar line in pixels, beyond which the point is considered an outlier and is not used for computing the final fundamental matrix. It can be set to something like 1-3, depending on ints of the same size and format as points1 .
OutputArray	mask	Output array of N elements, every element of which is set to 0 for outliers and to 1 for the other points. The array is computed only in the RANSAC and LMedS methods.

Returns

Type	Description
Mat	essential matrix

FindFundamentalMat(IEnumerable<Point2d>, IEnumerable<Point2d>, FundamentalMatMethods, Double, Double, OutputArray)

Calculates a fundamental matrix from the corresponding points in two images.

Declaration

public static Mat FindFundamentalMat(IEnumerable<Point2d> points1, IEnumerable<Point2d> points2, FundamentalMatMethods method = FundamentalMatMethods.Ransac, double param1 = 3, double param2 = 0.99, OutputArray mask = null)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2d>	points1	Array of N points from the first image. The point coordinates should be floating-point (single or double precision).
IEnumerable<OpenCvSharp.Point2d>	points2	Array of the second image points of the same size and format as points1 .
FundamentalMatMethods	method	Method for computing a fundamental matrix.
System.Double	param1	Parameter used for RANSAC. It is the maximum distance from a point to an epipolar line in pixels, beyond which the point is considered an outlier and is not used for computing the final fundamental matrix. It can be set to something like 1-3, depending on the accuracy of the point localization, image resolution, and the image noise.
System.Double	param2	Parameter used for the RANSAC or LMedS methods only. It specifies a desirable level of confidence (probability) that the estimated matrix is correct.
OutputArray	mask	Output array of N elements, every element of which is set to 0 for outliers and to 1 for the other points. The array is computed only in the RANSAC and LMedS methods. For other methods, it is set to all 1’s.

Returns

Type	Description
Mat	fundamental matrix

FindFundamentalMat(IEnumerable<Point2f>, IEnumerable<Point2f>, FundamentalMatMethods, Double, Double, OutputArray)

Calculates a fundamental matrix from the corresponding points in two images.

Declaration

public static Mat FindFundamentalMat(IEnumerable<Point2f> points1, IEnumerable<Point2f> points2, FundamentalMatMethods method = FundamentalMatMethods.Ransac, double param1 = 3, double param2 = 0.99, OutputArray mask = null)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points1	Array of N points from the first image. The point coordinates should be floating-point (single or double precision).
IEnumerable<OpenCvSharp.Point2f>	points2	Array of the second image points of the same size and format as points1 .
FundamentalMatMethods	method	Method for computing a fundamental matrix.
System.Double	param1	Parameter used for RANSAC. It is the maximum distance from a point to an epipolar line in pixels, beyond which the point is considered an outlier and is not used for computing the final fundamental matrix. It can be set to something like 1-3, depending on the accuracy of the point localization, image resolution, and the image noise.
System.Double	param2	Parameter used for the RANSAC or LMedS methods only. It specifies a desirable level of confidence (probability) that the estimated matrix is correct.
OutputArray	mask	Output array of N elements, every element of which is set to 0 for outliers and to 1 for the other points. The array is computed only in the RANSAC and LMedS methods. For other methods, it is set to all 1’s.

Returns

Type	Description
Mat	fundamental matrix

FindFundamentalMat(InputArray, InputArray, FundamentalMatMethods, Double, Double, OutputArray)

Calculates a fundamental matrix from the corresponding points in two images.

Declaration

public static Mat FindFundamentalMat(InputArray points1, InputArray points2, FundamentalMatMethods method = FundamentalMatMethods.Ransac, double param1 = 3, double param2 = 0.99, OutputArray mask = null)

Parameters

Type	Name	Description
InputArray	points1	Array of N points from the first image. The point coordinates should be floating-point (single or double precision).
InputArray	points2	Array of the second image points of the same size and format as points1 .
FundamentalMatMethods	method	Method for computing a fundamental matrix.
System.Double	param1	Parameter used for RANSAC. It is the maximum distance from a point to an epipolar line in pixels, beyond which the point is considered an outlier and is not used for computing the final fundamental matrix. It can be set to something like 1-3, depending on the accuracy of the point localization, image resolution, and the image noise.
System.Double	param2	Parameter used for the RANSAC or LMedS methods only. It specifies a desirable level of confidence (probability) that the estimated matrix is correct.
OutputArray	mask	Output array of N elements, every element of which is set to 0 for outliers and to 1 for the other points. The array is computed only in the RANSAC and LMedS methods. For other methods, it is set to all 1’s.

Returns

Type	Description
Mat	fundamental matrix

FindHomography(IEnumerable<Point2d>, IEnumerable<Point2d>, HomographyMethods, Double, OutputArray, Int32, Double)

computes the best-fit perspective transformation mapping srcPoints to dstPoints.

Declaration

public static Mat FindHomography(IEnumerable<Point2d> srcPoints, IEnumerable<Point2d> dstPoints, HomographyMethods method = HomographyMethods.None, double ransacReprojThreshold = 3, OutputArray mask = null, int maxIters = 2000, double confidence = 0.995)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2d>	srcPoints	Coordinates of the points in the original plane
IEnumerable<OpenCvSharp.Point2d>	dstPoints	Coordinates of the points in the target plane
HomographyMethods	method	Method used to computed a homography matrix.
System.Double	ransacReprojThreshold	Maximum allowed reprojection error to treat a point pair as an inlier (used in the RANSAC method only)
OutputArray	mask	Optional output mask set by a robust method ( CV_RANSAC or CV_LMEDS ). Note that the input mask values are ignored.
System.Int32	maxIters	The maximum number of RANSAC iterations.
System.Double	confidence	Confidence level, between 0 and 1.

Returns

Type	Description
Mat

FindHomography(InputArray, InputArray, HomographyMethods, Double, OutputArray, Int32, Double)

computes the best-fit perspective transformation mapping srcPoints to dstPoints.

Declaration

public static Mat FindHomography(InputArray srcPoints, InputArray dstPoints, HomographyMethods method = HomographyMethods.None, double ransacReprojThreshold = 3, OutputArray mask = null, int maxIters = 2000, double confidence = 0.995)

Parameters

Type	Name	Description
InputArray	srcPoints	Coordinates of the points in the original plane, a matrix of the type CV_32FC2
InputArray	dstPoints	Coordinates of the points in the target plane, a matrix of the type CV_32FC2
HomographyMethods	method	Method used to computed a homography matrix.
System.Double	ransacReprojThreshold	Maximum allowed reprojection error to treat a point pair as an inlier (used in the RANSAC method only)
OutputArray	mask	Optional output mask set by a robust method ( CV_RANSAC or CV_LMEDS ). Note that the input mask values are ignored.
System.Int32	maxIters	The maximum number of RANSAC iterations.
System.Double	confidence	Confidence level, between 0 and 1.

Returns

Type	Description
Mat

FindHomography(InputArray, InputArray, OutputArray, UsacParams)

computes the best-fit perspective transformation mapping srcPoints to dstPoints.

Declaration

public static Mat FindHomography(InputArray srcPoints, InputArray dstPoints, OutputArray mask, UsacParams params)

Parameters

Type	Name	Description
InputArray	srcPoints	Coordinates of the points in the original plane, a matrix of the type CV_32FC2
InputArray	dstPoints	Coordinates of the points in the target plane, a matrix of the type CV_32FC2
OutputArray	mask	Optional output mask set by a robust method ( CV_RANSAC or CV_LMEDS ). Note that the input mask values are ignored.
UsacParams	params

Returns

Type	Description
Mat

FindNonZero(InputArray, OutputArray)

returns the list of locations of non-zero pixels

Declaration

public static void FindNonZero(InputArray src, OutputArray idx)

Parameters

Type	Name	Description
InputArray	src
OutputArray	idx

FindTransformECC(InputArray, InputArray, InputOutputArray, MotionTypes, TermCriteria, InputArray, Int32)

Finds the geometric transform (warp) between two images in terms of the ECC criterion @cite EP08 .

Declaration

public static double FindTransformECC(InputArray templateImage, InputArray inputImage, InputOutputArray warpMatrix, MotionTypes motionType, TermCriteria criteria, InputArray inputMask = null, int gaussFiltSize = 5)

Parameters

Type	Name	Description
InputArray	templateImage	single-channel template image; CV_8U or CV_32F array.
InputArray	inputImage	single-channel input image which should be warped with the final warpMatrix in order to provide an image similar to templateImage, same type as templateImage.
InputOutputArray	warpMatrix	floating-point \f$2\times 3\f$ or \f$3\times 3\f$ mapping matrix (warp).
MotionTypes	motionType	parameter, specifying the type of motion
OpenCvSharp.TermCriteria	criteria	parameter, specifying the termination criteria of the ECC algorithm; criteria.epsilon defines the threshold of the increment in the correlation coefficient between two iterations(a negative criteria.epsilon makes criteria.maxcount the only termination criterion). Default values are shown in the declaration above.
InputArray	inputMask	An optional mask to indicate valid values of inputImage.
System.Int32	gaussFiltSize	An optional value indicating size of gaussian blur filter; (DEFAULT: 5)

Returns

Type	Description
System.Double

FindTransformECC(InputArray, InputArray, InputOutputArray, MotionTypes, Nullable<TermCriteria>, InputArray)

Finds the geometric transform (warp) between two images in terms of the ECC criterion @cite EP08 .

Declaration

public static double FindTransformECC(InputArray templateImage, InputArray inputImage, InputOutputArray warpMatrix, MotionTypes motionType = MotionTypes.Affine, TermCriteria? criteria = null, InputArray inputMask = null)

Parameters

Type	Name	Description
InputArray	templateImage	single-channel template image; CV_8U or CV_32F array.
InputArray	inputImage	single-channel input image which should be warped with the final warpMatrix in order to provide an image similar to templateImage, same type as templateImage.
InputOutputArray	warpMatrix	floating-point \f$2\times 3\f$ or \f$3\times 3\f$ mapping matrix (warp).
MotionTypes	motionType	parameter, specifying the type of motion
System.Nullable<OpenCvSharp.TermCriteria>	criteria	parameter, specifying the termination criteria of the ECC algorithm; criteria.epsilon defines the threshold of the increment in the correlation coefficient between two iterations(a negative criteria.epsilon makes criteria.maxcount the only termination criterion). Default values are shown in the declaration above.
InputArray	inputMask	An optional mask to indicate valid values of inputImage.

Returns

Type	Description
System.Double

FitEllipse(IEnumerable<Point>)

Fits ellipse to the set of 2D points.

Declaration

public static RotatedRect FitEllipse(IEnumerable<Point> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipse(IEnumerable<Point2f>)

Fits ellipse to the set of 2D points.

Declaration

public static RotatedRect FitEllipse(IEnumerable<Point2f> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipse(InputArray)

Fits ellipse to the set of 2D points.

Declaration

public static RotatedRect FitEllipse(InputArray points)

Parameters

Type	Name	Description
InputArray	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipseAMS(IEnumerable<Point>)

Fits an ellipse around a set of 2D points.

The function calculates the ellipse that fits a set of 2D points. It returns the rotated rectangle in which the ellipse is inscribed. The Approximate Mean Square(AMS) proposed by @cite Taubin1991 is used.

Declaration

public static RotatedRect FitEllipseAMS(IEnumerable<Point> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipseAMS(IEnumerable<Point2f>)

Fits an ellipse around a set of 2D points.

The function calculates the ellipse that fits a set of 2D points. It returns the rotated rectangle in which the ellipse is inscribed. The Approximate Mean Square(AMS) proposed by @cite Taubin1991 is used.

Declaration

public static RotatedRect FitEllipseAMS(IEnumerable<Point2f> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipseAMS(InputArray)

Fits an ellipse around a set of 2D points.

The function calculates the ellipse that fits a set of 2D points. It returns the rotated rectangle in which the ellipse is inscribed. The Approximate Mean Square(AMS) proposed by @cite Taubin1991 is used.

Declaration

public static RotatedRect FitEllipseAMS(InputArray points)

Parameters

Type	Name	Description
InputArray	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipseDirect(IEnumerable<Point>)

Fits an ellipse around a set of 2D points.

The function calculates the ellipse that fits a set of 2D points. It returns the rotated rectangle in which the ellipse is inscribed. The Direct least square(Direct) method by @cite Fitzgibbon1999 is used.

Declaration

public static RotatedRect FitEllipseDirect(IEnumerable<Point> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipseDirect(IEnumerable<Point2f>)

Fits an ellipse around a set of 2D points.

The function calculates the ellipse that fits a set of 2D points. It returns the rotated rectangle in which the ellipse is inscribed. The Direct least square(Direct) method by @cite Fitzgibbon1999 is used.

Declaration

public static RotatedRect FitEllipseDirect(IEnumerable<Point2f> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitEllipseDirect(InputArray)

Fits an ellipse around a set of 2D points.

The function calculates the ellipse that fits a set of 2D points. It returns the rotated rectangle in which the ellipse is inscribed. The Direct least square(Direct) method by @cite Fitzgibbon1999 is used.

Declaration

public static RotatedRect FitEllipseDirect(InputArray points)

Parameters

Type	Name	Description
InputArray	points	Input 2D point set

Returns

Type	Description
OpenCvSharp.RotatedRect

FitLine(IEnumerable<Point>, DistanceTypes, Double, Double, Double)

Fits line to the set of 2D points using M-estimator algorithm

Declaration

public static Line2D FitLine(IEnumerable<Point> points, DistanceTypes distType, double param, double reps, double aeps)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	Input vector of 2D or 3D points
DistanceTypes	distType	Distance used by the M-estimator
System.Double	param	Numerical parameter ( C ) for some types of distances. If it is 0, an optimal value is chosen.
System.Double	reps	Sufficient accuracy for the radius (distance between the coordinate origin and the line).
System.Double	aeps	Sufficient accuracy for the angle. 0.01 would be a good default value for reps and aeps.

Returns

Type	Description
Line2D	Output line parameters.

FitLine(IEnumerable<Point2f>, DistanceTypes, Double, Double, Double)

Fits line to the set of 2D points using M-estimator algorithm

Declaration

public static Line2D FitLine(IEnumerable<Point2f> points, DistanceTypes distType, double param, double reps, double aeps)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	Input vector of 2D or 3D points
DistanceTypes	distType	Distance used by the M-estimator
System.Double	param	Numerical parameter ( C ) for some types of distances. If it is 0, an optimal value is chosen.
System.Double	reps	Sufficient accuracy for the radius (distance between the coordinate origin and the line).
System.Double	aeps	Sufficient accuracy for the angle. 0.01 would be a good default value for reps and aeps.

Returns

Type	Description
Line2D	Output line parameters.

FitLine(IEnumerable<Point3f>, DistanceTypes, Double, Double, Double)

Fits line to the set of 3D points using M-estimator algorithm

Declaration

public static Line3D FitLine(IEnumerable<Point3f> points, DistanceTypes distType, double param, double reps, double aeps)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3f>	points	Input vector of 2D or 3D points
DistanceTypes	distType	Distance used by the M-estimator
System.Double	param	Numerical parameter ( C ) for some types of distances. If it is 0, an optimal value is chosen.
System.Double	reps	Sufficient accuracy for the radius (distance between the coordinate origin and the line).
System.Double	aeps	Sufficient accuracy for the angle. 0.01 would be a good default value for reps and aeps.

Returns

Type	Description
Line3D	Output line parameters.

FitLine(IEnumerable<Point3i>, DistanceTypes, Double, Double, Double)

Fits line to the set of 3D points using M-estimator algorithm

Declaration

public static Line3D FitLine(IEnumerable<Point3i> points, DistanceTypes distType, double param, double reps, double aeps)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3i>	points	Input vector of 2D or 3D points
DistanceTypes	distType	Distance used by the M-estimator
System.Double	param	Numerical parameter ( C ) for some types of distances. If it is 0, an optimal value is chosen.
System.Double	reps	Sufficient accuracy for the radius (distance between the coordinate origin and the line).
System.Double	aeps	Sufficient accuracy for the angle. 0.01 would be a good default value for reps and aeps.

Returns

Type	Description
Line3D	Output line parameters.

FitLine(InputArray, OutputArray, DistanceTypes, Double, Double, Double)

Fits line to the set of 2D points using M-estimator algorithm

Declaration

public static void FitLine(InputArray points, OutputArray line, DistanceTypes distType, double param, double reps, double aeps)

Parameters

Type	Name	Description
InputArray	points	Input vector of 2D or 3D points
OutputArray	line	Output line parameters. In case of 2D fitting, it should be a vector of 4 elements (like Vec4f) - (vx, vy, x0, y0), where (vx, vy) is a normalized vector collinear to the line and (x0, y0) is a point on the line. In case of 3D fitting, it should be a vector of 6 elements (like Vec6f) - (vx, vy, vz, x0, y0, z0), where (vx, vy, vz) is a normalized vector collinear to the line and (x0, y0, z0) is a point on the line.
DistanceTypes	distType	Distance used by the M-estimator
System.Double	param	Numerical parameter ( C ) for some types of distances. If it is 0, an optimal value is chosen.
System.Double	reps	Sufficient accuracy for the radius (distance between the coordinate origin and the line).
System.Double	aeps	Sufficient accuracy for the angle. 0.01 would be a good default value for reps and aeps.

Flip(InputArray, OutputArray, FlipMode)

reverses the order of the rows, columns or both in a matrix

Declaration

public static void Flip(InputArray src, OutputArray dst, FlipMode flipCode)

Parameters

Type	Name	Description
InputArray	src	The source array
OutputArray	dst	The destination array; will have the same size and same type as src
FlipMode	flipCode	Specifies how to flip the array: 0 means flipping around the x-axis, positive (e.g., 1) means flipping around y-axis, and negative (e.g., -1) means flipping around both axes. See also the discussion below for the formulas.

FloodFill(InputOutputArray, InputOutputArray, Point, Scalar)

Fills a connected component with the given color.

Declaration

public static int FloodFill(InputOutputArray image, InputOutputArray mask, Point seedPoint, Scalar newVal)

Parameters

Type	Name	Description
InputOutputArray	image	Input/output 1- or 3-channel, 8-bit, or floating-point image. It is modified by the function unless the FLOODFILL_MASK_ONLY flag is set in the second variant of the function. See the details below.
InputOutputArray	mask	(For the second function only) Operation mask that should be a single-channel 8-bit image, 2 pixels wider and 2 pixels taller. The function uses and updates the mask, so you take responsibility of initializing the mask content. Flood-filling cannot go across non-zero pixels in the mask. For example, an edge detector output can be used as a mask to stop filling at edges. It is possible to use the same mask in multiple calls to the function to make sure the filled area does not overlap.
OpenCvSharp.Point	seedPoint	Starting point.
OpenCvSharp.Scalar	newVal	New value of the repainted domain pixels.

Returns

Type	Description
System.Int32

FloodFill(InputOutputArray, InputOutputArray, Point, Scalar, out Rect, Nullable<Scalar>, Nullable<Scalar>, FloodFillFlags)

Fills a connected component with the given color.

Declaration

public static int FloodFill(InputOutputArray image, InputOutputArray mask, Point seedPoint, Scalar newVal, out Rect rect, Scalar? loDiff = null, Scalar? upDiff = null, FloodFillFlags flags = FloodFillFlags.Link4)

Parameters

Type	Name	Description
InputOutputArray	image	Input/output 1- or 3-channel, 8-bit, or floating-point image. It is modified by the function unless the FLOODFILL_MASK_ONLY flag is set in the second variant of the function. See the details below.
InputOutputArray	mask	(For the second function only) Operation mask that should be a single-channel 8-bit image, 2 pixels wider and 2 pixels taller. The function uses and updates the mask, so you take responsibility of initializing the mask content. Flood-filling cannot go across non-zero pixels in the mask. For example, an edge detector output can be used as a mask to stop filling at edges. It is possible to use the same mask in multiple calls to the function to make sure the filled area does not overlap.
OpenCvSharp.Point	seedPoint	Starting point.
OpenCvSharp.Scalar	newVal	New value of the repainted domain pixels.
OpenCvSharp.Rect	rect	Optional output parameter set by the function to the minimum bounding rectangle of the repainted domain.
System.Nullable<OpenCvSharp.Scalar>	loDiff	Maximal lower brightness/color difference between the currently observed pixel and one of its neighbors belonging to the component, or a seed pixel being added to the component.
System.Nullable<OpenCvSharp.Scalar>	upDiff	Maximal upper brightness/color difference between the currently observed pixel and one of its neighbors belonging to the component, or a seed pixel being added to the component.
FloodFillFlags	flags	Operation flags. Lower bits contain a connectivity value, 4 (default) or 8, used within the function. Connectivity determines which neighbors of a pixel are considered. Using FloodFillFlags.MaskOnly will fill in the mask using the grey value 255 (white).

Returns

Type	Description
System.Int32

FloodFill(InputOutputArray, Point, Scalar)

Fills a connected component with the given color.

Declaration

public static int FloodFill(InputOutputArray image, Point seedPoint, Scalar newVal)

Parameters

Type	Name	Description
InputOutputArray	image	Input/output 1- or 3-channel, 8-bit, or floating-point image. It is modified by the function unless the FLOODFILL_MASK_ONLY flag is set in the second variant of the function. See the details below.
OpenCvSharp.Point	seedPoint	Starting point.
OpenCvSharp.Scalar	newVal	New value of the repainted domain pixels.

Returns

Type	Description
System.Int32

FloodFill(InputOutputArray, Point, Scalar, out Rect, Nullable<Scalar>, Nullable<Scalar>, FloodFillFlags)

Fills a connected component with the given color.

Declaration

public static int FloodFill(InputOutputArray image, Point seedPoint, Scalar newVal, out Rect rect, Scalar? loDiff = null, Scalar? upDiff = null, FloodFillFlags flags = FloodFillFlags.Link4)

Parameters

Type	Name	Description
InputOutputArray	image	Input/output 1- or 3-channel, 8-bit, or floating-point image. It is modified by the function unless the FLOODFILL_MASK_ONLY flag is set in the second variant of the function. See the details below.
OpenCvSharp.Point	seedPoint	Starting point.
OpenCvSharp.Scalar	newVal	New value of the repainted domain pixels.
OpenCvSharp.Rect	rect	Optional output parameter set by the function to the minimum bounding rectangle of the repainted domain.
System.Nullable<OpenCvSharp.Scalar>	loDiff	Maximal lower brightness/color difference between the currently observed pixel and one of its neighbors belonging to the component, or a seed pixel being added to the component.
System.Nullable<OpenCvSharp.Scalar>	upDiff	Maximal upper brightness/color difference between the currently observed pixel and one of its neighbors belonging to the component, or a seed pixel being added to the component.
FloodFillFlags	flags	Operation flags. Lower bits contain a connectivity value, 4 (default) or 8, used within the function. Connectivity determines which neighbors of a pixel are considered. Using FloodFillFlags.MaskOnly will fill in the mask using the grey value 255 (white).

Returns

Type	Description
System.Int32

Format(InputArray, FormatType)

Declaration

public static string Format(InputArray mtx, FormatType format = FormatType.Default)

Parameters

Type	Name	Description
InputArray	mtx
FormatType	format

Returns

Type	Description
System.String

GaussianBlur(InputArray, OutputArray, Size, Double, Double, BorderTypes)

Blurs an image using a Gaussian filter.

Declaration

public static void GaussianBlur(InputArray src, OutputArray dst, Size ksize, double sigmaX, double sigmaY = 0, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	input image; the image can have any number of channels, which are processed independently, but the depth should be CV_8U, CV_16U, CV_16S, CV_32F or CV_64F.
OutputArray	dst	output image of the same size and type as src.
OpenCvSharp.Size	ksize	Gaussian kernel size. ksize.width and ksize.height can differ but they both must be positive and odd. Or, they can be zero’s and then they are computed from sigma* .
System.Double	sigmaX	Gaussian kernel standard deviation in X direction.
System.Double	sigmaY	Gaussian kernel standard deviation in Y direction; if sigmaY is zero, it is set to be equal to sigmaX, if both sigmas are zeros, they are computed from ksize.width and ksize.height, respectively (see getGaussianKernel() for details); to fully control the result regardless of possible future modifications of all this semantics, it is recommended to specify all of ksize, sigmaX, and sigmaY.
BorderTypes	borderType	pixel extrapolation method

Gemm(InputArray, InputArray, Double, InputArray, Double, OutputArray, GemmFlags)

implements generalized matrix product algorithm GEMM from BLAS

Declaration

public static void Gemm(InputArray src1, InputArray src2, double alpha, InputArray src3, double gamma, OutputArray dst, GemmFlags flags = GemmFlags.None)

Parameters

Type	Name	Description
InputArray	src1
InputArray	src2
System.Double	alpha
InputArray	src3
System.Double	gamma
OutputArray	dst
GemmFlags	flags

GetAffineTransform(IEnumerable<Point2f>, IEnumerable<Point2f>)

Calculates an affine transform from three pairs of the corresponding points. The function calculates the 2×3 matrix of an affine transform.

Declaration

public static Mat GetAffineTransform(IEnumerable<Point2f> src, IEnumerable<Point2f> dst)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	src	Coordinates of triangle vertices in the source image.
IEnumerable<OpenCvSharp.Point2f>	dst	Coordinates of the corresponding triangle vertices in the destination image.

Returns

Type	Description
Mat

GetAffineTransform(InputArray, InputArray)

Calculates an affine transform from three pairs of the corresponding points. The function calculates the 2×3 matrix of an affine transform.

Declaration

public static Mat GetAffineTransform(InputArray src, InputArray dst)

Parameters

Type	Name	Description
InputArray	src	Coordinates of triangle vertices in the source image.
InputArray	dst	Coordinates of the corresponding triangle vertices in the destination image.

Returns

Type	Description
Mat

GetBuildInformation()

Returns full configuration time cmake output.

Returned value is raw cmake output including version control system revision, compiler version, compiler flags, enabled modules and third party libraries, etc.Output format depends on target architecture.

Declaration

public static string GetBuildInformation()

Returns

Type	Description
System.String

GetCpuFeaturesLine()

Returns list of CPU features enabled during compilation. Returned value is a string containing space separated list of CPU features with following markers:

• no markers - baseline features
• prefix * - features enabled in dispatcher
• suffix ? - features enabled but not available in HW

Declaration

public static string GetCpuFeaturesLine()

Returns

Type	Description
System.String

Examples

SSE SSE2 SSE3* SSE4.1 *SSE4.2 *FP16* AVX *AVX2* AVX512-SKX?

GetCpuTickCount()

Returns the number of CPU ticks.

The function returns the current number of CPU ticks on some architectures(such as x86, x64, PowerPC). On other platforms the function is equivalent to getTickCount.It can also be used for very accurate time measurements, as well as for RNG initialization.Note that in case of multi-CPU systems a thread, from which getCPUTickCount is called, can be suspended and resumed at another CPU with its own counter. So, theoretically (and practically) the subsequent calls to the function do not necessary return the monotonously increasing values. Also, since a modern CPU varies the CPU frequency depending on the load, the number of CPU clocks spent in some code cannot be directly converted to time units.Therefore, getTickCount is generally a preferable solution for measuringexecution time.

Declaration

public static long GetCpuTickCount()

Returns

Type	Description
System.Int64

GetDefaultNewCameraMatrix(InputArray, Nullable<Size>, Boolean)

returns the default new camera matrix (by default it is the same as cameraMatrix unless centerPricipalPoint=true)

Declaration

public static Mat GetDefaultNewCameraMatrix(InputArray cameraMatrix, Size? imgSize = null, bool centerPrincipalPoint = false)

Parameters

Type	Name	Description
InputArray	cameraMatrix	Input camera matrix.
System.Nullable<OpenCvSharp.Size>	imgSize	Camera view image size in pixels.
System.Boolean	centerPrincipalPoint	Location of the principal point in the new camera matrix. The parameter indicates whether this location should be at the image center or not.

Returns

Type	Description
Mat	the camera matrix that is either an exact copy of the input cameraMatrix (when centerPrinicipalPoint=false), or the modified one (when centerPrincipalPoint=true).

GetDerivKernels(OutputArray, OutputArray, Int32, Int32, Int32, Boolean, Nullable<MatType>)

Returns filter coefficients for computing spatial image derivatives.

Declaration

public static void GetDerivKernels(OutputArray kx, OutputArray ky, int dx, int dy, int ksize, bool normalize = false, MatType? ktype = null)

Parameters

Type	Name	Description
OutputArray	kx	Output matrix of row filter coefficients. It has the type ktype.
OutputArray	ky	Output matrix of column filter coefficients. It has the type ktype.
System.Int32	dx	Derivative order in respect of x.
System.Int32	dy	Derivative order in respect of y.
System.Int32	ksize	Aperture size. It can be CV_SCHARR, 1, 3, 5, or 7.
System.Boolean	normalize	Flag indicating whether to normalize (scale down) the filter coefficients or not. Theoretically, the coefficients should have the denominator \f$=2^{ksize*2-dx-dy-2}\f$. If you are going to filter floating-point images, you are likely to use the normalized kernels. But if you compute derivatives of an 8-bit image, store the results in a 16-bit image, and wish to preserve all the fractional bits, you may want to set normalize = false.
System.Nullable<OpenCvSharp.MatType>	ktype	Type of filter coefficients. It can be CV_32f or CV_64F.

GetFontScaleFromHeight(HersheyFonts, Int32, Int32)

Calculates the font-specific size to use to achieve a given height in pixels.

Declaration

public static double GetFontScaleFromHeight(HersheyFonts fontFace, int pixelHeight, int thickness = 1)

Parameters

Type	Name	Description
HersheyFonts	fontFace	Font to use, see cv::HersheyFonts.
System.Int32	pixelHeight	Pixel height to compute the fontScale for
System.Int32	thickness	Thickness of lines used to render the text.See putText for details.

Returns

Type	Description
System.Double	The fontSize to use for cv::putText

GetGaborKernel(Size, Double, Double, Double, Double, Double, Int32)

Returns Gabor filter coefficients.

Declaration

public static Mat GetGaborKernel(Size ksize, double sigma, double theta, double lambd, double gamma, double psi, int ktype)

Parameters

Type	Name	Description
OpenCvSharp.Size	ksize	Size of the filter returned.
System.Double	sigma	Standard deviation of the gaussian envelope.
System.Double	theta	Orientation of the normal to the parallel stripes of a Gabor function.
System.Double	lambd	Wavelength of the sinusoidal factor.
System.Double	gamma	Spatial aspect ratio.
System.Double	psi	Phase offset.
System.Int32	ktype	Type of filter coefficients. It can be CV_32F or CV_64F.

Returns

Type	Description
Mat

Remarks

For more details about gabor filter equations and parameters, see: https://en.wikipedia.org/wiki/Gabor_filter

GetGaussianKernel(Int32, Double, Nullable<MatType>)

Returns Gaussian filter coefficients.

Declaration

public static Mat GetGaussianKernel(int ksize, double sigma, MatType? ktype = null)

Parameters

Type	Name	Description
System.Int32	ksize	Aperture size. It should be odd and positive.
System.Double	sigma	Gaussian standard deviation. If it is non-positive, it is computed from ksize as sigma = 0.3*((ksize-1)*0.5 - 1) + 0.8.
System.Nullable<OpenCvSharp.MatType>	ktype	Type of filter coefficients. It can be CV_32F or CV_64F.

Returns

Type	Description
Mat

GetHardwareFeatureName(CpuFeatures)

Returns feature name by ID. Returns empty string if feature is not defined

Declaration

public static string GetHardwareFeatureName(CpuFeatures feature)

Parameters

Type	Name	Description
CpuFeatures	feature

Returns

Type	Description
System.String

GetLogLevel()

Get global logging level

Declaration

public static LogLevel GetLogLevel()

Returns

Type	Description
LogLevel	logging level

GetMouseWheelDelta(MouseEventFlags)

Gets the mouse-wheel motion delta, when handling mouse-wheel events cv::EVENT_MOUSEWHEEL and cv::EVENT_MOUSEHWHEEL.

For regular mice with a scroll-wheel, delta will be a multiple of 120. The value 120 corresponds to a one notch rotation of the wheel or the threshold for action to be taken and one such action should occur for each delta.Some high-precision mice with higher-resolution freely-rotating wheels may generate smaller values.

For cv::EVENT_MOUSEWHEEL positive and negative values mean forward and backward scrolling, respectively.For cv::EVENT_MOUSEHWHEEL, where available, positive and negative values mean right and left scrolling, respectively.

Declaration

public static int GetMouseWheelDelta(MouseEventFlags flags)

Parameters

Type	Name	Description
MouseEventFlags	flags	The mouse callback flags parameter.

Returns

Type	Description
System.Int32

GetNearestPoint(IEnumerable<Point2f>, Single)

Declaration

public static int GetNearestPoint(IEnumerable<Point2f> recallPrecisionCurve, float lPrecision)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	recallPrecisionCurve
System.Single	lPrecision

Returns

Type	Description
System.Int32

GetNumberOfCpus()

Returns the number of logical CPUs available for the process.

Declaration

public static int GetNumberOfCpus()

Returns

Type	Description
System.Int32

GetNumThreads()

Returns the number of threads used by OpenCV for parallel regions.

Always returns 1 if OpenCV is built without threading support. The exact meaning of return value depends on the threading framework used by OpenCV library:

• TBB - The number of threads, that OpenCV will try to use for parallel regions. If there is any tbb::thread_scheduler_init in user code conflicting with OpenCV, then function returns default number of threads used by TBB library.
• OpenMP - An upper bound on the number of threads that could be used to form a new team.
• Concurrency - The number of threads, that OpenCV will try to use for parallel regions.
• GCD - Unsupported; returns the GCD thread pool limit(512) for compatibility.
• C= - The number of threads, that OpenCV will try to use for parallel regions, if before called setNumThreads with threads > 0, otherwise returns the number of logical CPUs, available for the process.

Declaration

public static int GetNumThreads()

Returns

Type	Description
System.Int32

GetOptimalDFTSize(Int32)

Returns the optimal DFT size for a given vector size.

Declaration

public static int GetOptimalDFTSize(int vecSize)

Parameters

Type	Name	Description
System.Int32	vecSize	vector size.

Returns

Type	Description
System.Int32

GetOptimalNewCameraMatrix(InputArray, InputArray, Size, Double, Size, out Rect, Boolean)

Returns the new camera matrix based on the free scaling parameter.

Declaration

public static Mat GetOptimalNewCameraMatrix(InputArray cameraMatrix, InputArray distCoeffs, Size imageSize, double alpha, Size newImgSize, out Rect validPixROI, bool centerPrincipalPoint = false)

Parameters

Type	Name	Description
InputArray	cameraMatrix	Input camera matrix.
InputArray	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the array is null, the zero distortion coefficients are assumed.
OpenCvSharp.Size	imageSize	Original image size.
System.Double	alpha	Free scaling parameter between 0 (when all the pixels in the undistorted image are valid) and 1 (when all the source image pixels are retained in the undistorted image).
OpenCvSharp.Size	newImgSize	Image size after rectification. By default,it is set to imageSize .
OpenCvSharp.Rect	validPixROI	Optional output rectangle that outlines all-good-pixels region in the undistorted image. See roi1, roi2 description in stereoRectify() .
System.Boolean	centerPrincipalPoint	Optional flag that indicates whether in the new camera matrix the principal point should be at the image center or not. By default, the principal point is chosen to best fit a subset of the source image (determined by alpha) to the corrected image.

Returns

Type	Description
Mat	optimal new camera matrix

GetOptimalNewCameraMatrix(Double[,], Double[], Size, Double, Size, out Rect, Boolean)

Returns the new camera matrix based on the free scaling parameter.

Declaration

public static double[, ] GetOptimalNewCameraMatrix(double[, ] cameraMatrix, double[] distCoeffs, Size imageSize, double alpha, Size newImgSize, out Rect validPixROI, bool centerPrincipalPoint = false)

Parameters

Type	Name	Description
System.Double[,]	cameraMatrix	Input camera matrix.
System.Double[]	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the array is null, the zero distortion coefficients are assumed.
OpenCvSharp.Size	imageSize	Original image size.
System.Double	alpha	Free scaling parameter between 0 (when all the pixels in the undistorted image are valid) and 1 (when all the source image pixels are retained in the undistorted image).
OpenCvSharp.Size	newImgSize	Image size after rectification. By default,it is set to imageSize .
OpenCvSharp.Rect	validPixROI	Optional output rectangle that outlines all-good-pixels region in the undistorted image. See roi1, roi2 description in stereoRectify() .
System.Boolean	centerPrincipalPoint	Optional flag that indicates whether in the new camera matrix the principal point should be at the image center or not. By default, the principal point is chosen to best fit a subset of the source image (determined by alpha) to the corrected image.

Returns

Type	Description
System.Double[,]	optimal new camera matrix

GetPerspectiveTransform(IEnumerable<Point2f>, IEnumerable<Point2f>)

Calculates a perspective transform from four pairs of the corresponding points. The function calculates the 3×3 matrix of a perspective transform.

Declaration

public static Mat GetPerspectiveTransform(IEnumerable<Point2f> src, IEnumerable<Point2f> dst)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	src	Coordinates of quadrangle vertices in the source image.
IEnumerable<OpenCvSharp.Point2f>	dst	Coordinates of the corresponding quadrangle vertices in the destination image.

Returns

Type	Description
Mat

GetPerspectiveTransform(InputArray, InputArray)

Calculates a perspective transform from four pairs of the corresponding points. The function calculates the 3×3 matrix of a perspective transform.

Declaration

public static Mat GetPerspectiveTransform(InputArray src, InputArray dst)

Parameters

Type	Name	Description
InputArray	src	Coordinates of quadrangle vertices in the source image.
InputArray	dst	Coordinates of the corresponding quadrangle vertices in the destination image.

Returns

Type	Description
Mat

GetRecall(IEnumerable<Point2f>, Single)

Declaration

public static float GetRecall(IEnumerable<Point2f> recallPrecisionCurve, float lPrecision)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	recallPrecisionCurve
System.Single	lPrecision

Returns

Type	Description
System.Single

GetRectSubPix(InputArray, Size, Point2f, OutputArray, Int32)

Retrieves a pixel rectangle from an image with sub-pixel accuracy.

Declaration

public static void GetRectSubPix(InputArray image, Size patchSize, Point2f center, OutputArray patch, int patchType = -1)

Parameters

Type	Name	Description
InputArray	image	Source image.
OpenCvSharp.Size	patchSize	Size of the extracted patch.
OpenCvSharp.Point2f	center	Floating point coordinates of the center of the extracted rectangle within the source image. The center must be inside the image.
OutputArray	patch	Extracted patch that has the size patchSize and the same number of channels as src .
System.Int32	patchType	Depth of the extracted pixels. By default, they have the same depth as src.

GetRotationMatrix2D(Point2f, Double, Double)

Calculates an affine matrix of 2D rotation.

Declaration

public static Mat GetRotationMatrix2D(Point2f center, double angle, double scale)

Parameters

Type	Name	Description
OpenCvSharp.Point2f	center	Center of the rotation in the source image.
System.Double	angle	Rotation angle in degrees. Positive values mean counter-clockwise rotation (the coordinate origin is assumed to be the top-left corner).
System.Double	scale	Isotropic scale factor.

Returns

Type	Description
Mat

GetStructuringElement(MorphShapes, Size)

Returns a structuring element of the specified size and shape for morphological operations. The function constructs and returns the structuring element that can be further passed to erode, dilate or morphologyEx.But you can also construct an arbitrary binary mask yourself and use it as the structuring element.

Declaration

public static Mat GetStructuringElement(MorphShapes shape, Size ksize)

Parameters

Type	Name	Description
MorphShapes	shape	Element shape that could be one of MorphShapes
OpenCvSharp.Size	ksize	Size of the structuring element.

Returns

Type	Description
Mat

GetStructuringElement(MorphShapes, Size, Point)

Returns a structuring element of the specified size and shape for morphological operations. The function constructs and returns the structuring element that can be further passed to erode, dilate or morphologyEx.But you can also construct an arbitrary binary mask yourself and use it as the structuring element.

Declaration

public static Mat GetStructuringElement(MorphShapes shape, Size ksize, Point anchor)

Parameters

Type	Name	Description
MorphShapes	shape	Element shape that could be one of MorphShapes
OpenCvSharp.Size	ksize	Size of the structuring element.
OpenCvSharp.Point	anchor	Anchor position within the element. The default value (−1,−1) means that the anchor is at the center. Note that only the shape of a cross-shaped element depends on the anchor position. In other cases the anchor just regulates how much the result of the morphological operation is shifted.

Returns

Type	Description
Mat

GetTextSize(String, HersheyFonts, Double, Int32, out Int32)

returns bounding box of the text string

Declaration

public static Size GetTextSize(string text, HersheyFonts fontFace, double fontScale, int thickness, out int baseLine)

Parameters

Type	Name	Description
System.String	text	Input text string.
HersheyFonts	fontFace	Font to use, see #HersheyFonts.
System.Double	fontScale	Font scale factor that is multiplied by the font-specific base size.
System.Int32	thickness	Thickness of lines used to render the text. See #putText for details.
System.Int32	baseLine	baseLine y-coordinate of the baseline relative to the bottom-most text

Returns

Type	Description
OpenCvSharp.Size	The size of a box that contains the specified text.

GetTheRNG()

Returns the thread-local Random number generator

Declaration

public static RNG GetTheRNG()

Returns

Type	Description
RNG

GetThreadNum()

Returns the index of the currently executed thread within the current parallel region. Always returns 0 if called outside of parallel region. @deprecated Current implementation doesn't corresponding to this documentation. The exact meaning of the return value depends on the threading framework used by OpenCV library:

• TBB - Unsupported with current 4.1 TBB release.Maybe will be supported in future.
• OpenMP - The thread number, within the current team, of the calling thread.
• Concurrency - An ID for the virtual processor that the current context is executing on(0 for master thread and unique number for others, but not necessary 1,2,3,...).
• GCD - System calling thread's ID. Never returns 0 inside parallel region.
• C= - The index of the current parallel task.

Declaration

public static int GetThreadNum()

Returns

Type	Description
System.Int32

GetTickCount()

Returns the number of ticks. The function returns the number of ticks after the certain event (for example, when the machine was turned on). It can be used to initialize RNG or to measure a function execution time by reading the tick count before and after the function call.

Declaration

public static long GetTickCount()

Returns

Type	Description
System.Int64

GetTickFrequency()

Returns the number of ticks per second. The function returns the number of ticks per second.That is, the following code computes the execution time in seconds:

Declaration

public static double GetTickFrequency()

Returns

Type	Description
System.Double

GetTrackbarPos(String, String)

Returns the trackbar position.

Declaration

public static int GetTrackbarPos(string trackbarName, string winName)

Parameters

Type	Name	Description
System.String	trackbarName	Name of the trackbar.
System.String	winName	Name of the window that is the parent of the trackbar.

Returns

Type	Description
System.Int32	trackbar position

GetValidDisparityROI(Rect, Rect, Int32, Int32, Int32)

computes valid disparity ROI from the valid ROIs of the rectified images (that are returned by cv::stereoRectify())

Declaration

public static Rect GetValidDisparityROI(Rect roi1, Rect roi2, int minDisparity, int numberOfDisparities, int SADWindowSize)

Parameters

Type	Name	Description
OpenCvSharp.Rect	roi1
OpenCvSharp.Rect	roi2
System.Int32	minDisparity
System.Int32	numberOfDisparities
System.Int32	SADWindowSize

Returns

Type	Description
OpenCvSharp.Rect

GetVersionMajor()

Returns major library version

Declaration

public static int GetVersionMajor()

Returns

Type	Description
System.Int32

GetVersionMinor()

Returns minor library version

Declaration

public static int GetVersionMinor()

Returns

Type	Description
System.Int32

GetVersionRevision()

Returns revision field of the library version

Declaration

public static int GetVersionRevision()

Returns

Type	Description
System.Int32

GetVersionString()

Returns library version string. For example "3.4.1-dev".

Declaration

public static string GetVersionString()

Returns

Type	Description
System.String

GetWindowHandle(String)

get native window handle (HWND in case of Win32 and Widget in case of X Window)

Declaration

public static IntPtr GetWindowHandle(string windowName)

Parameters

Type	Name	Description
System.String	windowName

Returns

Type	Description
IntPtr

GetWindowImageRect(String)

Provides rectangle of image in the window. The function getWindowImageRect returns the client screen coordinates, width and height of the image rendering area.

Declaration

public static Rect GetWindowImageRect(string winName)

Parameters

Type	Name	Description
System.String	winName	Name of the window.

Returns

Type	Description
OpenCvSharp.Rect

GetWindowProperty(String, WindowPropertyFlags)

Provides parameters of a window.

Declaration

public static double GetWindowProperty(string winName, WindowPropertyFlags propId)

Parameters

Type	Name	Description
System.String	winName	Name of the window.
WindowPropertyFlags	propId	Window property to retrieve.

Returns

Type	Description
System.Double

GoodFeaturesToTrack(InputArray, Int32, Double, Double, InputArray, Int32, Boolean, Double)

finds the strong enough corners where the cornerMinEigenVal() or cornerHarris() report the local maxima

Declaration

public static Point2f[] GoodFeaturesToTrack(InputArray src, int maxCorners, double qualityLevel, double minDistance, InputArray mask, int blockSize, bool useHarrisDetector, double k)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit or floating-point 32-bit, single-channel image.
System.Int32	maxCorners	Maximum number of corners to return. If there are more corners than are found, the strongest of them is returned.
System.Double	qualityLevel	Parameter characterizing the minimal accepted quality of image corners. The parameter value is multiplied by the best corner quality measure, which is the minimal eigenvalue or the Harris function response (see cornerHarris() ). The corners with the quality measure less than the product are rejected. For example, if the best corner has the quality measure = 1500, and the qualityLevel=0.01, then all the corners with the quality measure less than 15 are rejected.
System.Double	minDistance	Minimum possible Euclidean distance between the returned corners.
InputArray	mask	Optional region of interest. If the image is not empty (it needs to have the type CV_8UC1 and the same size as image ), it specifies the region in which the corners are detected.
System.Int32	blockSize	Size of an average block for computing a derivative covariation matrix over each pixel neighborhood.
System.Boolean	useHarrisDetector	Parameter indicating whether to use a Harris detector
System.Double	k	Free parameter of the Harris detector.

Returns

Type	Description
OpenCvSharp.Point2f[]	Output vector of detected corners.

GrabCut(InputArray, InputOutputArray, Rect, InputOutputArray, InputOutputArray, Int32, GrabCutModes)

Segments the image using GrabCut algorithm

Declaration

public static void GrabCut(InputArray img, InputOutputArray mask, Rect rect, InputOutputArray bgdModel, InputOutputArray fgdModel, int iterCount, GrabCutModes mode)

Parameters

Type	Name	Description
InputArray	img	Input 8-bit 3-channel image.
InputOutputArray	mask	Input/output 8-bit single-channel mask. The mask is initialized by the function when mode is set to GC_INIT_WITH_RECT. Its elements may have Cv2.GC_BGD / Cv2.GC_FGD / Cv2.GC_PR_BGD / Cv2.GC_PR_FGD
OpenCvSharp.Rect	rect	ROI containing a segmented object. The pixels outside of the ROI are marked as "obvious background". The parameter is only used when mode==GC_INIT_WITH_RECT.
InputOutputArray	bgdModel	Temporary array for the background model. Do not modify it while you are processing the same image.
InputOutputArray	fgdModel	Temporary arrays for the foreground model. Do not modify it while you are processing the same image.
System.Int32	iterCount	Number of iterations the algorithm should make before returning the result. Note that the result can be refined with further calls with mode==GC_INIT_WITH_MASK or mode==GC_EVAL .
GrabCutModes	mode	Operation mode that could be one of GrabCutFlag value.

GroupRectangles(IList<Rect>, Int32, Double)

Groups the object candidate rectangles.

Declaration

public static void GroupRectangles(IList<Rect> rectList, int groupThreshold, double eps = 0.2)

Parameters

Type	Name	Description
IList<OpenCvSharp.Rect>	rectList	Input/output vector of rectangles. Output vector includes retained and grouped rectangles.
System.Int32	groupThreshold	Minimum possible number of rectangles minus 1. The threshold is used in a group of rectangles to retain it.
System.Double	eps

GroupRectangles(IList<Rect>, Int32, Double, out Int32[], out Double[])

Groups the object candidate rectangles.

Declaration

public static void GroupRectangles(IList<Rect> rectList, int groupThreshold, double eps, out int[] weights, out double[] levelWeights)

Parameters

Type	Name	Description
IList<OpenCvSharp.Rect>	rectList
System.Int32	groupThreshold
System.Double	eps
System.Int32[]	weights
System.Double[]	levelWeights

GroupRectangles(IList<Rect>, out Int32[], out Double[], Int32, Double)

Groups the object candidate rectangles.

Declaration

public static void GroupRectangles(IList<Rect> rectList, out int[] rejectLevels, out double[] levelWeights, int groupThreshold, double eps = 0.2)

Parameters

Type	Name	Description
IList<OpenCvSharp.Rect>	rectList
System.Int32[]	rejectLevels
System.Double[]	levelWeights
System.Int32	groupThreshold
System.Double	eps

GroupRectangles(IList<Rect>, out Int32[], Int32, Double)

Groups the object candidate rectangles.

Declaration

public static void GroupRectangles(IList<Rect> rectList, out int[] weights, int groupThreshold, double eps = 0.2)

Parameters

Type	Name	Description
IList<OpenCvSharp.Rect>	rectList	Input/output vector of rectangles. Output vector includes retained and grouped rectangles.
System.Int32[]	weights
System.Int32	groupThreshold	Minimum possible number of rectangles minus 1. The threshold is used in a group of rectangles to retain it.
System.Double	eps	Relative difference between sides of the rectangles to merge them into a group.

GroupRectanglesMeanshift(IList<Rect>, out Double[], out Double[], Double, Nullable<Size>)

Declaration

public static void GroupRectanglesMeanshift(IList<Rect> rectList, out double[] foundWeights, out double[] foundScales, double detectThreshold = 0, Size? winDetSize = null)

Parameters

Type	Name	Description
IList<OpenCvSharp.Rect>	rectList
System.Double[]	foundWeights
System.Double[]	foundScales
System.Double	detectThreshold
System.Nullable<OpenCvSharp.Size>	winDetSize

HaveImageReader(String)

Declaration

public static bool HaveImageReader(string fileName)

Parameters

Type	Name	Description
System.String	fileName

Returns

Type	Description
System.Boolean

HaveImageWriter(String)

Declaration

public static bool HaveImageWriter(string fileName)

Parameters

Type	Name	Description
System.String	fileName

Returns

Type	Description
System.Boolean

HConcat(IEnumerable<Mat>, OutputArray)

Applies horizontal concatenation to given matrices.

Declaration

public static void HConcat(IEnumerable<Mat> src, OutputArray dst)

Parameters

Type	Name	Description
IEnumerable<Mat>	src	input array or vector of matrices. all of the matrices must have the same number of rows and the same depth.
OutputArray	dst	output array. It has the same number of rows and depth as the src, and the sum of cols of the src.

HConcat(InputArray, InputArray, OutputArray)

Applies horizontal concatenation to given matrices.

Declaration

public static void HConcat(InputArray src1, InputArray src2, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src1	first input array to be considered for horizontal concatenation.
InputArray	src2	second input array to be considered for horizontal concatenation.
OutputArray	dst	output array. It has the same number of rows and depth as the src1 and src2, and the sum of cols of the src1 and src2.

HoughCircles(InputArray, HoughModes, Double, Double, Double, Double, Int32, Int32)

Finds circles in a grayscale image using a Hough transform.

Declaration

public static CircleSegment[] HoughCircles(InputArray image, HoughModes method, double dp, double minDist, double param1 = 100, double param2 = 100, int minRadius = 0, int maxRadius = 0)

Parameters

Type	Name	Description
InputArray	image	The 8-bit, single-channel, grayscale input image
HoughModes	method	The available methods are HoughMethods.Gradient and HoughMethods.GradientAlt
System.Double	dp	The inverse ratio of the accumulator resolution to the image resolution.
System.Double	minDist	Minimum distance between the centers of the detected circles.
System.Double	param1	The first method-specific parameter. [By default this is 100]
System.Double	param2	The second method-specific parameter. [By default this is 100]
System.Int32	minRadius	Minimum circle radius. [By default this is 0]
System.Int32	maxRadius	Maximum circle radius. [By default this is 0]

Returns

Type	Description
CircleSegment[]	The output vector found circles. Each vector is encoded as 3-element floating-point vector (x, y, radius)

HoughLines(InputArray, Double, Double, Int32, Double, Double)

Finds lines in a binary image using standard Hough transform.

Declaration

public static LineSegmentPolar[] HoughLines(InputArray image, double rho, double theta, int threshold, double srn = 0, double stn = 0)

Parameters

Type	Name	Description
InputArray	image	The 8-bit, single-channel, binary source image. The image may be modified by the function
System.Double	rho	Distance resolution of the accumulator in pixels
System.Double	theta	Angle resolution of the accumulator in radians
System.Int32	threshold	The accumulator threshold parameter. Only those lines are returned that get enough votes ( > threshold )
System.Double	srn	For the multi-scale Hough transform it is the divisor for the distance resolution rho. [By default this is 0]
System.Double	stn	For the multi-scale Hough transform it is the divisor for the distance resolution theta. [By default this is 0]

Returns

Type	Description
LineSegmentPolar[]	The output vector of lines. Each line is represented by a two-element vector (rho, theta) . rho is the distance from the coordinate origin (0,0) (top-left corner of the image) and theta is the line rotation angle in radians

HoughLinesP(InputArray, Double, Double, Int32, Double, Double)

Finds lines segments in a binary image using probabilistic Hough transform.

Declaration

public static LineSegmentPoint[] HoughLinesP(InputArray image, double rho, double theta, int threshold, double minLineLength = 0, double maxLineGap = 0)

Parameters

Type	Name	Description
InputArray	image
System.Double	rho	Distance resolution of the accumulator in pixels
System.Double	theta	Angle resolution of the accumulator in radians
System.Int32	threshold	The accumulator threshold parameter. Only those lines are returned that get enough votes ( > threshold )
System.Double	minLineLength	The minimum line length. Line segments shorter than that will be rejected. [By default this is 0]
System.Double	maxLineGap	The maximum allowed gap between points on the same line to link them. [By default this is 0]

Returns

Type	Description
LineSegmentPoint[]	The output lines. Each line is represented by a 4-element vector (x1, y1, x2, y2)

HoughLinesPointSet(InputArray, OutputArray, Int32, Int32, Double, Double, Double, Double, Double, Double)

Finds lines in a set of points using the standard Hough transform. The function finds lines in a set of points using a modification of the Hough transform.

Declaration

public static void HoughLinesPointSet(InputArray point, OutputArray lines, int linesMax, int threshold, double minRho, double maxRho, double rhoStep, double minTheta, double maxTheta, double thetaStep)

Parameters

Type	Name	Description
InputArray	point	Input vector of points. Each vector must be encoded as a Point vector \f$(x,y)\f$. Type must be CV_32FC2 or CV_32SC2.
OutputArray	lines	Output vector of found lines. Each vector is encoded as a vector<Vec3d>
System.Int32	linesMax	Max count of hough lines.
System.Int32	threshold	Accumulator threshold parameter. Only those lines are returned that get enough votes
System.Double	minRho	Minimum Distance value of the accumulator in pixels.
System.Double	maxRho	Maximum Distance value of the accumulator in pixels.
System.Double	rhoStep	Distance resolution of the accumulator in pixels.
System.Double	minTheta	Minimum angle value of the accumulator in radians.
System.Double	maxTheta	Maximum angle value of the accumulator in radians.
System.Double	thetaStep	Angle resolution of the accumulator in radians.

Idct(InputArray, OutputArray, DctFlags)

Performs inverse 1D or 2D Discrete Cosine Transformation

Declaration

public static void Idct(InputArray src, OutputArray dst, DctFlags flags = DctFlags.None)

Parameters

Type	Name	Description
InputArray	src	The source floating-point array
OutputArray	dst	The destination array; will have the same size and same type as src
DctFlags	flags	Transformation flags, a combination of DctFlag2 values

Idft(InputArray, OutputArray, DftFlags, Int32)

Performs an inverse Discrete Fourier transform of 1D or 2D floating-point array.

Declaration

public static void Idft(InputArray src, OutputArray dst, DftFlags flags = DftFlags.None, int nonzeroRows = 0)

Parameters

Type	Name	Description
InputArray	src	The source array, real or complex
OutputArray	dst	The destination array, which size and type depends on the flags
DftFlags	flags	Transformation flags, a combination of the DftFlag2 values
System.Int32	nonzeroRows	When the parameter != 0, the function assumes that only the first nonzeroRows rows of the input array ( DFT_INVERSE is not set) or only the first nonzeroRows of the output array ( DFT_INVERSE is set) contain non-zeros, thus the function can handle the rest of the rows more efficiently and thus save some time. This technique is very useful for computing array cross-correlation or convolution using DFT

IlluminationChange(InputArray, InputArray, OutputArray, Single, Single)

Applying an appropriate non-linear transformation to the gradient field inside the selection and then integrating back with a Poisson solver, modifies locally the apparent illumination of an image.

Declaration

public static void IlluminationChange(InputArray src, InputArray mask, OutputArray dst, float alpha = 0.2F, float beta = 0.4F)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
InputArray	mask	Input 8-bit 1 or 3-channel image.
OutputArray	dst	Output image with the same size and type as src.
System.Single	alpha	Value ranges between 0-2.
System.Single	beta	Value ranges between 0-2.

Remarks

This is useful to highlight under-exposed foreground objects or to reduce specular reflections.

ImDecode(InputArray, ImreadModes)

Reads image from the specified buffer in memory.

Declaration

public static Mat ImDecode(InputArray buf, ImreadModes flags)

Parameters

Type	Name	Description
InputArray	buf	The input array of vector of bytes.
ImreadModes	flags	The same flags as in imread

Returns

Type	Description
Mat

ImDecode(Mat, ImreadModes)

Reads image from the specified buffer in memory.

Declaration

public static Mat ImDecode(Mat buf, ImreadModes flags)

Parameters

Type	Name	Description
Mat	buf	The input array of vector of bytes.
ImreadModes	flags	The same flags as in imread

Returns

Type	Description
Mat

ImDecode(ReadOnlySpan<Byte>, ImreadModes)

Reads image from the specified buffer in memory.

Declaration

public static Mat ImDecode(ReadOnlySpan<byte> span, ImreadModes flags)

Parameters

Type	Name	Description
ReadOnlySpan<System.Byte>	span	The input slice of bytes.
ImreadModes	flags	The same flags as in imread

Returns

Type	Description
Mat

ImDecode(Byte[], ImreadModes)

Reads image from the specified buffer in memory.

Declaration

public static Mat ImDecode(byte[] buf, ImreadModes flags)

Parameters

Type	Name	Description
System.Byte[]	buf	The input array of vector of bytes.
ImreadModes	flags	The same flags as in imread

Returns

Type	Description
Mat

ImEncode(String, InputArray, out Byte[], ImageEncodingParam[])

Compresses the image and stores it in the memory buffer

Declaration

public static void ImEncode(string ext, InputArray img, out byte[] buf, params ImageEncodingParam[] prms)

Parameters

Type	Name	Description
System.String	ext	The file extension that defines the output format
InputArray	img	The image to be written
System.Byte[]	buf	Output buffer resized to fit the compressed image.
ImageEncodingParam[]	prms	Format-specific parameters.

ImEncode(String, InputArray, out Byte[], Int32[])

Compresses the image and stores it in the memory buffer

Declaration

public static bool ImEncode(string ext, InputArray img, out byte[] buf, int[] prms = null)

Parameters

Type	Name	Description
System.String	ext	The file extension that defines the output format
InputArray	img	The image to be written
System.Byte[]	buf	Output buffer resized to fit the compressed image.
System.Int32[]	prms	Format-specific parameters.

Returns

Type	Description
System.Boolean

ImRead(String, ImreadModes)

Loads an image from a file.

Declaration

public static Mat ImRead(string fileName, ImreadModes flags = ImreadModes.Color)

Parameters

Type	Name	Description
System.String	fileName	Name of file to be loaded.
ImreadModes	flags	Specifies color type of the loaded image

Returns

Type	Description
Mat

ImReadMulti(String, out Mat[], ImreadModes)

Loads a multi-page image from a file.

Declaration

public static bool ImReadMulti(string filename, out Mat[] mats, ImreadModes flags = ImreadModes.AnyColor)

Parameters

Type	Name	Description
System.String	filename	Name of file to be loaded.
Mat[]	mats	A vector of Mat objects holding each page, if more than one.
ImreadModes	flags	Flag that can take values of @ref cv::ImreadModes, default with IMREAD_ANYCOLOR.

Returns

Type	Description
System.Boolean

ImShow(String, Mat)

Displays the image in the specified window

Declaration

public static void ImShow(string winName, Mat mat)

Parameters

Type	Name	Description
System.String	winName	Name of the window.
Mat	mat	Image to be shown.

ImWrite(String, IEnumerable<Mat>, ImageEncodingParam[])

Saves an image to a specified file.

Declaration

public static bool ImWrite(string fileName, IEnumerable<Mat> img, params ImageEncodingParam[] prms)

Parameters

Type	Name	Description
System.String	fileName	Name of the file.
IEnumerable<Mat>	img	Image to be saved.
ImageEncodingParam[]	prms	Format-specific save parameters encoded as pairs

Returns

Type	Description
System.Boolean

ImWrite(String, IEnumerable<Mat>, Int32[])

Saves an image to a specified file.

Declaration

public static bool ImWrite(string fileName, IEnumerable<Mat> img, int[] prms = null)

Parameters

Type	Name	Description
System.String	fileName	Name of the file.
IEnumerable<Mat>	img	Image to be saved.
System.Int32[]	prms	Format-specific save parameters encoded as pairs

Returns

Type	Description
System.Boolean

ImWrite(String, Mat, ImageEncodingParam[])

Saves an image to a specified file.

Declaration

public static bool ImWrite(string fileName, Mat img, params ImageEncodingParam[] prms)

Parameters

Type	Name	Description
System.String	fileName	Name of the file.
Mat	img	Image to be saved.
ImageEncodingParam[]	prms	Format-specific save parameters encoded as pairs

Returns

Type	Description
System.Boolean

ImWrite(String, Mat, Int32[])

Saves an image to a specified file.

Declaration

public static bool ImWrite(string fileName, Mat img, int[] prms = null)

Parameters

Type	Name	Description
System.String	fileName	Name of the file.
Mat	img	Image to be saved.
System.Int32[]	prms	Format-specific save parameters encoded as pairs

Returns

Type	Description
System.Boolean

InitCameraMatrix2D(IEnumerable<IEnumerable<Point3f>>, IEnumerable<IEnumerable<Point2f>>, Size, Double)

initializes camera matrix from a few 3D points and the corresponding projections.

Declaration

public static Mat InitCameraMatrix2D(IEnumerable<IEnumerable<Point3f>> objectPoints, IEnumerable<IEnumerable<Point2f>> imagePoints, Size imageSize, double aspectRatio = 1)

Parameters

Type	Name	Description
IEnumerable<IEnumerable<OpenCvSharp.Point3f>>	objectPoints	Vector of vectors of the calibration pattern points in the calibration pattern coordinate space. In the old interface all the per-view vectors are concatenated.
IEnumerable<IEnumerable<OpenCvSharp.Point2f>>	imagePoints	Vector of vectors of the projections of the calibration pattern points. In the old interface all the per-view vectors are concatenated.
OpenCvSharp.Size	imageSize	Image size in pixels used to initialize the principal point.
System.Double	aspectRatio	If it is zero or negative, both f_x and f_y are estimated independently. Otherwise, f_x = f_y * aspectRatio .

Returns

Type	Description
Mat

InitCameraMatrix2D(IEnumerable<Mat>, IEnumerable<Mat>, Size, Double)

initializes camera matrix from a few 3D points and the corresponding projections.

Declaration

public static Mat InitCameraMatrix2D(IEnumerable<Mat> objectPoints, IEnumerable<Mat> imagePoints, Size imageSize, double aspectRatio = 1)

Parameters

Type	Name	Description
IEnumerable<Mat>	objectPoints	Vector of vectors (vector<vector<Point3d>>) of the calibration pattern points in the calibration pattern coordinate space. In the old interface all the per-view vectors are concatenated.
IEnumerable<Mat>	imagePoints	Vector of vectors (vector<vector<Point2d>>) of the projections of the calibration pattern points. In the old interface all the per-view vectors are concatenated.
OpenCvSharp.Size	imageSize	Image size in pixels used to initialize the principal point.
System.Double	aspectRatio	If it is zero or negative, both f_x and f_y are estimated independently. Otherwise, f_x = f_y * aspectRatio .

Returns

Type	Description
Mat

InitUndistortRectifyMap(InputArray, InputArray, InputArray, InputArray, Size, MatType, OutputArray, OutputArray)

initializes maps for cv::remap() to correct lens distortion and optionally rectify the image

Declaration

public static void InitUndistortRectifyMap(InputArray cameraMatrix, InputArray distCoeffs, InputArray r, InputArray newCameraMatrix, Size size, MatType m1Type, OutputArray map1, OutputArray map2)

Parameters

Type	Name	Description
InputArray	cameraMatrix
InputArray	distCoeffs
InputArray	r
InputArray	newCameraMatrix
OpenCvSharp.Size	size
OpenCvSharp.MatType	m1Type
OutputArray	map1
OutputArray	map2

InitWideAngleProjMap(InputArray, InputArray, Size, Int32, MatType, OutputArray, OutputArray, ProjectionType, Double)

initializes maps for cv::remap() for wide-angle

Declaration

public static float InitWideAngleProjMap(InputArray cameraMatrix, InputArray distCoeffs, Size imageSize, int destImageWidth, MatType m1Type, OutputArray map1, OutputArray map2, ProjectionType projType, double alpha = 0)

Parameters

Type	Name	Description
InputArray	cameraMatrix
InputArray	distCoeffs
OpenCvSharp.Size	imageSize
System.Int32	destImageWidth
OpenCvSharp.MatType	m1Type
OutputArray	map1
OutputArray	map2
ProjectionType	projType
System.Double	alpha

Returns

Type	Description
System.Single

Inpaint(InputArray, InputArray, OutputArray, Double, InpaintMethod)

Restores the selected region in an image using the region neighborhood.

Declaration

public static void Inpaint(InputArray src, InputArray inpaintMask, OutputArray dst, double inpaintRadius, InpaintMethod flags)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit, 16-bit unsigned or 32-bit float 1-channel or 8-bit 3-channel image.
InputArray	inpaintMask	Inpainting mask, 8-bit 1-channel image. Non-zero pixels indicate the area that needs to be inpainted.
OutputArray	dst	Output image with the same size and type as src.
System.Double	inpaintRadius	Radius of a circular neighborhood of each point inpainted that is considered by the algorithm.
InpaintMethod	flags	Inpainting method that could be cv::INPAINT_NS or cv::INPAINT_TELEA

InRange(InputArray, InputArray, InputArray, OutputArray)

Checks if array elements lie between the elements of two other arrays.

Declaration

public static void InRange(InputArray src, InputArray lowerb, InputArray upperb, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	first input array.
InputArray	lowerb	inclusive lower boundary array or a scalar.
InputArray	upperb	inclusive upper boundary array or a scalar.
OutputArray	dst	output array of the same size as src and CV_8U type.

InRange(InputArray, Scalar, Scalar, OutputArray)

Checks if array elements lie between the elements of two other arrays.

Declaration

public static void InRange(InputArray src, Scalar lowerb, Scalar upperb, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	first input array.
OpenCvSharp.Scalar	lowerb	inclusive lower boundary array or a scalar.
OpenCvSharp.Scalar	upperb	inclusive upper boundary array or a scalar.
OutputArray	dst	output array of the same size as src and CV_8U type.

InsertChannel(InputArray, InputOutputArray, Int32)

inserts a single channel to dst (coi is 0-based index)

Declaration

public static void InsertChannel(InputArray src, InputOutputArray dst, int coi)

Parameters

Type	Name	Description
InputArray	src
InputOutputArray	dst
System.Int32	coi

Integral(InputArray, OutputArray, OutputArray, OutputArray, Nullable<MatType>, Nullable<MatType>)

Calculates the integral of an image. The function calculates one or more integral images for the source image.

Declaration

public static void Integral(InputArray src, OutputArray sum, OutputArray sqsum, OutputArray tilted, MatType? sdepth = null, MatType? sqdepth = null)

Parameters

Type	Name	Description
InputArray	src	input image as W×H, 8-bit or floating-point (32f or 64f).
OutputArray	sum	integral image as (W+1)×(H+1) , 32-bit integer or floating-point (32f or 64f).
OutputArray	sqsum	integral image for squared pixel values; it is (W+1)×(H+1), double-precision floating-point (64f) array.
OutputArray	tilted	integral for the image rotated by 45 degrees; it is (W+1)×(H+1) array with the same data type as sum.
System.Nullable<OpenCvSharp.MatType>	sdepth	desired depth of the integral and the tilted integral images, CV_32S, CV_32F, or CV_64F.
System.Nullable<OpenCvSharp.MatType>	sqdepth	desired depth of the integral image of squared pixel values, CV_32F or CV_64F.

Integral(InputArray, OutputArray, OutputArray, Nullable<MatType>)

Calculates the integral of an image. The function calculates one or more integral images for the source image.

Declaration

public static void Integral(InputArray src, OutputArray sum, OutputArray sqsum, MatType? sdepth = null)

Parameters

Type	Name	Description
InputArray	src
OutputArray	sum
OutputArray	sqsum
System.Nullable<OpenCvSharp.MatType>	sdepth

Integral(InputArray, OutputArray, Nullable<MatType>)

Calculates the integral of an image. The function calculates one or more integral images for the source image.

Declaration

public static void Integral(InputArray src, OutputArray sum, MatType? sdepth = null)

Parameters

Type	Name	Description
InputArray	src
OutputArray	sum
System.Nullable<OpenCvSharp.MatType>	sdepth

IntersectConvexConvex(IEnumerable<Point>, IEnumerable<Point>, out Point[], Boolean)

finds intersection of two convex polygons

Declaration

public static float IntersectConvexConvex(IEnumerable<Point> p1, IEnumerable<Point> p2, out Point[] p12, bool handleNested = true)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	p1
IEnumerable<OpenCvSharp.Point>	p2
OpenCvSharp.Point[]	p12
System.Boolean	handleNested

Returns

Type	Description
System.Single

IntersectConvexConvex(IEnumerable<Point2f>, IEnumerable<Point2f>, out Point2f[], Boolean)

finds intersection of two convex polygons

Declaration

public static float IntersectConvexConvex(IEnumerable<Point2f> p1, IEnumerable<Point2f> p2, out Point2f[] p12, bool handleNested = true)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	p1
IEnumerable<OpenCvSharp.Point2f>	p2
OpenCvSharp.Point2f[]	p12
System.Boolean	handleNested

Returns

Type	Description
System.Single

IntersectConvexConvex(InputArray, InputArray, OutputArray, Boolean)

finds intersection of two convex polygons

Declaration

public static float IntersectConvexConvex(InputArray p1, InputArray p2, OutputArray p12, bool handleNested = true)

Parameters

Type	Name	Description
InputArray	p1
InputArray	p2
OutputArray	p12
System.Boolean	handleNested

Returns

Type	Description
System.Single

Invert(InputArray, OutputArray, DecompTypes)

computes inverse or pseudo-inverse matrix

Declaration

public static double Invert(InputArray src, OutputArray dst, DecompTypes flags = DecompTypes.LU)

Parameters

Type	Name	Description
InputArray	src	The source floating-point MxN matrix
OutputArray	dst	The destination matrix; will have NxM size and the same type as src
DecompTypes	flags	The inversion method

Returns

Type	Description
System.Double

InvertAffineTransform(InputArray, OutputArray)

Inverts an affine transformation.

Declaration

public static void InvertAffineTransform(InputArray m, OutputArray im)

Parameters

Type	Name	Description
InputArray	m	Original affine transformation.
OutputArray	im	Output reverse affine transformation.

IsContourConvex(IEnumerable<Point>)

returns true if the contour is convex. Does not support contours with self-intersection

Declaration

public static bool IsContourConvex(IEnumerable<Point> contour)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	contour	Input vector of 2D points

Returns

Type	Description
System.Boolean

IsContourConvex(IEnumerable<Point2f>)

returns true if the contour is convex. D oes not support contours with self-intersection

Declaration

public static bool IsContourConvex(IEnumerable<Point2f> contour)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	contour	Input vector of 2D points

Returns

Type	Description
System.Boolean

IsContourConvex(InputArray)

returns true if the contour is convex. Does not support contours with self-intersection

Declaration

public static bool IsContourConvex(InputArray contour)

Parameters

Type	Name	Description
InputArray	contour	Input vector of 2D points

Returns

Type	Description
System.Boolean

Kmeans(InputArray, Int32, InputOutputArray, TermCriteria, Int32, KMeansFlags, OutputArray)

Finds centers of clusters and groups input samples around the clusters.

Declaration

public static double Kmeans(InputArray data, int k, InputOutputArray bestLabels, TermCriteria criteria, int attempts, KMeansFlags flags, OutputArray centers = null)

Parameters

Type	Name	Description
InputArray	data	Data for clustering. An array of N-Dimensional points with float coordinates is needed.
System.Int32	k	Number of clusters to split the set by.
InputOutputArray	bestLabels	Input/output integer array that stores the cluster indices for every sample.
OpenCvSharp.TermCriteria	criteria	The algorithm termination criteria, that is, the maximum number of iterations and/or the desired accuracy. The accuracy is specified as criteria.epsilon. As soon as each of the cluster centers moves by less than criteria.epsilon on some iteration, the algorithm stops.
System.Int32	attempts	Flag to specify the number of times the algorithm is executed using different initial labellings. The algorithm returns the labels that yield the best compactness (see the last function parameter).
KMeansFlags	flags	Flag that can take values of cv::KmeansFlags
OutputArray	centers	Output matrix of the cluster centers, one row per each cluster center.

Returns

Type

Description

System.Double

The function returns the compactness measure that is computed as \f[\sum _i | \texttt{samples} _i - \texttt{centers} _{ \texttt{labels} _i} | ^2\f] after every attempt. The best (minimum) value is chosen and the corresponding labels and the compactness value are returned by the function. Basically, you can use only the core of the function, set the number of attempts to 1, initialize labels each time using a custom algorithm, pass them with the ( flags = #KMEANS_USE_INITIAL_LABELS ) flag, and then choose the best (most-compact) clustering.

Laplacian(InputArray, OutputArray, MatType, Int32, Double, Double, BorderTypes)

Calculates the Laplacian of an image

Declaration

public static void Laplacian(InputArray src, OutputArray dst, MatType ddepth, int ksize = 1, double scale = 1, double delta = 0, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	Source image
OutputArray	dst	Destination image; will have the same size and the same number of channels as src
OpenCvSharp.MatType	ddepth	The desired depth of the destination image
System.Int32	ksize	The aperture size used to compute the second-derivative filters
System.Double	scale	The optional scale factor for the computed Laplacian values (by default, no scaling is applied
System.Double	delta	The optional delta value, added to the results prior to storing them in dst
BorderTypes	borderType	The pixel extrapolation method

Line(InputOutputArray, Point, Point, Scalar, Int32, LineTypes, Int32)

Draws a line segment connecting two points

Declaration

public static void Line(InputOutputArray img, Point pt1, Point pt2, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	The image.
OpenCvSharp.Point	pt1	First point of the line segment.
OpenCvSharp.Point	pt2	Second point of the line segment.
OpenCvSharp.Scalar	color	Line color.
System.Int32	thickness	Line thickness. [By default this is 1]
LineTypes	lineType	Type of the line. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the point coordinates. [By default this is 0]

Line(InputOutputArray, Int32, Int32, Int32, Int32, Scalar, Int32, LineTypes, Int32)

Draws a line segment connecting two points

Declaration

public static void Line(InputOutputArray img, int pt1X, int pt1Y, int pt2X, int pt2Y, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	The image.
System.Int32	pt1X	First point's x-coordinate of the line segment.
System.Int32	pt1Y	First point's y-coordinate of the line segment.
System.Int32	pt2X	Second point's x-coordinate of the line segment.
System.Int32	pt2Y	Second point's y-coordinate of the line segment.
OpenCvSharp.Scalar	color	Line color.
System.Int32	thickness	Line thickness. [By default this is 1]
LineTypes	lineType	Type of the line. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the point coordinates. [By default this is 0]

LinearPolar(InputArray, OutputArray, Point2f, Double, InterpolationFlags)

Remaps an image to polar space.

Declaration

public static void LinearPolar(InputArray src, OutputArray dst, Point2f center, double maxRadius, InterpolationFlags flags)

Parameters

Type	Name	Description
InputArray	src	Source image
OutputArray	dst	Destination image
OpenCvSharp.Point2f	center	The transformation center
System.Double	maxRadius	Inverse magnitude scale parameter
InterpolationFlags	flags	A combination of interpolation methods, see cv::InterpolationFlags

Log(InputArray, OutputArray)

computes natural logarithm of absolute value of each matrix element: dst = log(abs(src))

Declaration

public static void Log(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	The source array
OutputArray	dst	The destination array; will have the same size and same type as src

LogPolar(InputArray, OutputArray, Point2f, Double, InterpolationFlags)

Remaps an image to log-polar space.

Declaration

public static void LogPolar(InputArray src, OutputArray dst, Point2f center, double m, InterpolationFlags flags)

Parameters

Type	Name	Description
InputArray	src	Source image
OutputArray	dst	Destination image
OpenCvSharp.Point2f	center	The transformation center; where the output precision is maximal
System.Double	m	Magnitude scale parameter.
InterpolationFlags	flags	A combination of interpolation methods, see cv::InterpolationFlags

LUT(InputArray, InputArray, OutputArray)

transforms array of numbers using a lookup table: dst(i)=lut(src(i))

Declaration

public static void LUT(InputArray src, InputArray lut, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	Source array of 8-bit elements
InputArray	lut	Look-up table of 256 elements. In the case of multi-channel source array, the table should either have a single channel (in this case the same table is used for all channels) or the same number of channels as in the source array
OutputArray	dst	Destination array; will have the same size and the same number of channels as src, and the same depth as lut

LUT(InputArray, Byte[], OutputArray)

transforms array of numbers using a lookup table: dst(i)=lut(src(i))

Declaration

public static void LUT(InputArray src, byte[] lut, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	Source array of 8-bit elements
System.Byte[]	lut	Look-up table of 256 elements. In the case of multi-channel source array, the table should either have a single channel (in this case the same table is used for all channels) or the same number of channels as in the source array
OutputArray	dst	Destination array; will have the same size and the same number of channels as src, and the same depth as lut

Magnitude(InputArray, InputArray, OutputArray)

Calculates the magnitude of 2D vectors.

Declaration

public static void Magnitude(InputArray x, InputArray y, OutputArray magnitude)

Parameters

Type	Name	Description
InputArray	x	floating-point array of x-coordinates of the vectors.
InputArray	y	floating-point array of y-coordinates of the vectors; it must have the same size as x.
OutputArray	magnitude	output array of the same size and type as x.

Mahalanobis(InputArray, InputArray, InputArray)

Calculates the Mahalanobis distance between two vectors.

Declaration

public static double Mahalanobis(InputArray v1, InputArray v2, InputArray icovar)

Parameters

Type	Name	Description
InputArray	v1	first 1D input vector.
InputArray	v2	second 1D input vector.
InputArray	icovar	inverse covariance matrix.

Returns

Type	Description
System.Double

MatchShapes(IEnumerable<Point>, IEnumerable<Point>, ShapeMatchModes, Double)

Compares two shapes.

Declaration

public static double MatchShapes(IEnumerable<Point> contour1, IEnumerable<Point> contour2, ShapeMatchModes method, double parameter = 0)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	contour1	First contour or grayscale image.
IEnumerable<OpenCvSharp.Point>	contour2	Second contour or grayscale image.
ShapeMatchModes	method	Comparison method
System.Double	parameter	Method-specific parameter (not supported now)

Returns

Type	Description
System.Double

MatchShapes(InputArray, InputArray, ShapeMatchModes, Double)

Compares two shapes.

Declaration

public static double MatchShapes(InputArray contour1, InputArray contour2, ShapeMatchModes method, double parameter = 0)

Parameters

Type	Name	Description
InputArray	contour1	First contour or grayscale image.
InputArray	contour2	Second contour or grayscale image.
ShapeMatchModes	method	Comparison method
System.Double	parameter	Method-specific parameter (not supported now)

Returns

Type	Description
System.Double

MatchTemplate(InputArray, InputArray, OutputArray, TemplateMatchModes, InputArray)

Computes the proximity map for the raster template and the image where the template is searched for

Declaration

public static void MatchTemplate(InputArray image, InputArray templ, OutputArray result, TemplateMatchModes method, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	image	Image where the search is running; should be 8-bit or 32-bit floating-point
InputArray	templ	Searched template; must be not greater than the source image and have the same data type
OutputArray	result	A map of comparison results; will be single-channel 32-bit floating-point. If image is WxH and templ is wxh then result will be (W-w+1) x (H-h+1).
TemplateMatchModes	method	Specifies the comparison method
InputArray	mask	Mask of searched template. It must have the same datatype and size with templ. It is not set by default.

MatMulDeriv(InputArray, InputArray, OutputArray, OutputArray)

computes derivatives of the matrix product w.r.t each of the multiplied matrix coefficients

Declaration

public static void MatMulDeriv(InputArray a, InputArray b, OutputArray dABdA, OutputArray dABdB)

Parameters

Type	Name	Description
InputArray	a	First multiplied matrix.
InputArray	b	Second multiplied matrix.
OutputArray	dABdA	First output derivative matrix d(AB)/dA of size A.rowsB.cols X A.rows*A.cols .
OutputArray	dABdB	Second output derivative matrix d(AB)/dB of size A.rowsB.cols X B.rows*B.cols .

Max(InputArray, InputArray, OutputArray)

computes per-element maximum of two arrays (dst = max(src1, src2))

Declaration

public static void Max(InputArray src1, InputArray src2, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src1
InputArray	src2
OutputArray	dst

Max(Mat, Mat, Mat)

computes per-element maximum of two arrays (dst = max(src1, src2))

Declaration

public static void Max(Mat src1, Mat src2, Mat dst)

Parameters

Type	Name	Description
Mat	src1
Mat	src2
Mat	dst

Max(Mat, Double, Mat)

computes per-element maximum of array and scalar (dst = max(src1, src2))

Declaration

public static void Max(Mat src1, double src2, Mat dst)

Parameters

Type	Name	Description
Mat	src1
System.Double	src2
Mat	dst

Mean(InputArray, InputArray)

computes mean value of selected array elements

Declaration

public static Scalar Mean(InputArray src, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	The source array; it should have 1 to 4 channels (so that the result can be stored in Scalar)
InputArray	mask	The optional operation mask

Returns

Type	Description
OpenCvSharp.Scalar

MeanShift(InputArray, ref Rect, TermCriteria)

Finds an object on a back projection image.

Declaration

public static int MeanShift(InputArray probImage, ref Rect window, TermCriteria criteria)

Parameters

Type	Name	Description
InputArray	probImage	Back projection of the object histogram.
OpenCvSharp.Rect	window	Initial search window.
OpenCvSharp.TermCriteria	criteria	Stop criteria for the iterative search algorithm.

Returns

Type	Description
System.Int32	Number of iterations CAMSHIFT took to converge.

MeanStdDev(InputArray, OutputArray, OutputArray, InputArray)

computes mean value and standard deviation of all or selected array elements

Declaration

public static void MeanStdDev(InputArray src, OutputArray mean, OutputArray stddev, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	The source array; it should have 1 to 4 channels (so that the results can be stored in Scalar's)
OutputArray	mean	The output parameter: computed mean value
OutputArray	stddev	The output parameter: computed standard deviation
InputArray	mask	The optional operation mask

MeanStdDev(InputArray, out Scalar, out Scalar, InputArray)

computes mean value and standard deviation of all or selected array elements

Declaration

public static void MeanStdDev(InputArray src, out Scalar mean, out Scalar stddev, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	The source array; it should have 1 to 4 channels (so that the results can be stored in Scalar's)
OpenCvSharp.Scalar	mean	The output parameter: computed mean value
OpenCvSharp.Scalar	stddev	The output parameter: computed standard deviation
InputArray	mask	The optional operation mask

MedianBlur(InputArray, OutputArray, Int32)

Smoothes image using median filter

Declaration

public static void MedianBlur(InputArray src, OutputArray dst, int ksize)

Parameters

Type	Name	Description
InputArray	src	The source 1-, 3- or 4-channel image. When ksize is 3 or 5, the image depth should be CV_8U , CV_16U or CV_32F. For larger aperture sizes it can only be CV_8U
OutputArray	dst	The destination array; will have the same size and the same type as src
System.Int32	ksize	The aperture linear size. It must be odd and more than 1, i.e. 3, 5, 7 ...

Merge(Mat[], Mat)

makes multi-channel array out of several single-channel arrays

Declaration

public static void Merge(Mat[] mv, Mat dst)

Parameters

Type	Name	Description
Mat[]	mv
Mat	dst

Min(InputArray, InputArray, OutputArray)

computes per-element minimum of two arrays (dst = min(src1, src2))

Declaration

public static void Min(InputArray src1, InputArray src2, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src1
InputArray	src2
OutputArray	dst

Min(Mat, Mat, Mat)

computes per-element minimum of two arrays (dst = min(src1, src2))

Declaration

public static void Min(Mat src1, Mat src2, Mat dst)

Parameters

Type	Name	Description
Mat	src1
Mat	src2
Mat	dst

Min(Mat, Double, Mat)

computes per-element minimum of array and scalar (dst = min(src1, src2))

Declaration

public static void Min(Mat src1, double src2, Mat dst)

Parameters

Type	Name	Description
Mat	src1
System.Double	src2
Mat	dst

MinAreaRect(IEnumerable<Point>)

Finds the minimum area rotated rectangle enclosing a 2D point set.

Declaration

public static RotatedRect MinAreaRect(IEnumerable<Point> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.

Returns

Type	Description
OpenCvSharp.RotatedRect

MinAreaRect(IEnumerable<Point2f>)

Finds the minimum area rotated rectangle enclosing a 2D point set.

Declaration

public static RotatedRect MinAreaRect(IEnumerable<Point2f> points)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.

Returns

Type	Description
OpenCvSharp.RotatedRect

MinAreaRect(InputArray)

Finds the minimum area rotated rectangle enclosing a 2D point set.

Declaration

public static RotatedRect MinAreaRect(InputArray points)

Parameters

Type	Name	Description
InputArray	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.

Returns

Type	Description
OpenCvSharp.RotatedRect

MinEnclosingCircle(IEnumerable<Point>, out Point2f, out Single)

Finds the minimum area circle enclosing a 2D point set.

Declaration

public static void MinEnclosingCircle(IEnumerable<Point> points, out Point2f center, out float radius)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.
OpenCvSharp.Point2f	center	The output center of the circle
System.Single	radius	The output radius of the circle

MinEnclosingCircle(IEnumerable<Point2f>, out Point2f, out Single)

Finds the minimum area circle enclosing a 2D point set.

Declaration

public static void MinEnclosingCircle(IEnumerable<Point2f> points, out Point2f center, out float radius)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.
OpenCvSharp.Point2f	center	The output center of the circle
System.Single	radius	The output radius of the circle

MinEnclosingCircle(InputArray, out Point2f, out Single)

Finds the minimum area circle enclosing a 2D point set.

Declaration

public static void MinEnclosingCircle(InputArray points, out Point2f center, out float radius)

Parameters

Type	Name	Description
InputArray	points	The input 2D point set, represented by CV_32SC2 or CV_32FC2 matrix.
OpenCvSharp.Point2f	center	The output center of the circle
System.Single	radius	The output radius of the circle

MinEnclosingTriangle(IEnumerable<Point>, out Point2f[])

Finds a triangle of minimum area enclosing a 2D point set and returns its area.

Declaration

public static double MinEnclosingTriangle(IEnumerable<Point> points, out Point2f[] triangle)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	points	Input vector of 2D points with depth CV_32S or CV_32F, stored in std::vector or Mat
OpenCvSharp.Point2f[]	triangle	Output vector of three 2D points defining the vertices of the triangle. The depth

Returns

Type	Description
System.Double	Triangle area

MinEnclosingTriangle(IEnumerable<Point2f>, out Point2f[])

Finds a triangle of minimum area enclosing a 2D point set and returns its area.

Declaration

public static double MinEnclosingTriangle(IEnumerable<Point2f> points, out Point2f[] triangle)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	points	Input vector of 2D points with depth CV_32S or CV_32F, stored in std::vector or Mat
OpenCvSharp.Point2f[]	triangle	Output vector of three 2D points defining the vertices of the triangle. The depth

Returns

Type	Description
System.Double	Triangle area

MinEnclosingTriangle(InputArray, OutputArray)

Finds a triangle of minimum area enclosing a 2D point set and returns its area.

Declaration

public static double MinEnclosingTriangle(InputArray points, OutputArray triangle)

Parameters

Type	Name	Description
InputArray	points	Input vector of 2D points with depth CV_32S or CV_32F, stored in std::vector or Mat
OutputArray	triangle	Output vector of three 2D points defining the vertices of the triangle. The depth

Returns

Type	Description
System.Double	Triangle area

MinMaxIdx(InputArray, out Double, out Double)

finds global minimum and maximum array elements and returns their values and their locations

Declaration

public static void MinMaxIdx(InputArray src, out double minVal, out double maxVal)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
System.Double	minVal	Pointer to returned minimum value
System.Double	maxVal	Pointer to returned maximum value

MinMaxIdx(InputArray, out Double, out Double, Int32[], Int32[], InputArray)

finds global minimum and maximum array elements and returns their values and their locations

Declaration

public static void MinMaxIdx(InputArray src, out double minVal, out double maxVal, int[] minIdx, int[] maxIdx, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
System.Double	minVal	Pointer to returned minimum value
System.Double	maxVal	Pointer to returned maximum value
System.Int32[]	minIdx
System.Int32[]	maxIdx
InputArray	mask

MinMaxIdx(InputArray, Int32[], Int32[])

finds global minimum and maximum array elements and returns their values and their locations

Declaration

public static void MinMaxIdx(InputArray src, int[] minIdx, int[] maxIdx)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
System.Int32[]	minIdx
System.Int32[]	maxIdx

MinMaxLoc(InputArray, out Point, out Point)

finds global minimum and maximum array elements and returns their values and their locations

Declaration

public static void MinMaxLoc(InputArray src, out Point minLoc, out Point maxLoc)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
OpenCvSharp.Point	minLoc	Pointer to returned minimum location
OpenCvSharp.Point	maxLoc	Pointer to returned maximum location

MinMaxLoc(InputArray, out Double, out Double)

finds global minimum and maximum array elements and returns their values and their locations

Declaration

public static void MinMaxLoc(InputArray src, out double minVal, out double maxVal)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
System.Double	minVal	Pointer to returned minimum value
System.Double	maxVal	Pointer to returned maximum value

MinMaxLoc(InputArray, out Double, out Double, out Point, out Point, InputArray)

finds global minimum and maximum array elements and returns their values and their locations

Declaration

public static void MinMaxLoc(InputArray src, out double minVal, out double maxVal, out Point minLoc, out Point maxLoc, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
System.Double	minVal	Pointer to returned minimum value
System.Double	maxVal	Pointer to returned maximum value
OpenCvSharp.Point	minLoc	Pointer to returned minimum location
OpenCvSharp.Point	maxLoc	Pointer to returned maximum location
InputArray	mask	The optional mask used to select a sub-array

MixChannels(Mat[], Mat[], Int32[])

copies selected channels from the input arrays to the selected channels of the output arrays

Declaration

public static void MixChannels(Mat[] src, Mat[] dst, int[] fromTo)

Parameters

Type	Name	Description
Mat[]	src
Mat[]	dst
System.Int32[]	fromTo

Moments(IEnumerable<Point>, Boolean)

Calculates all of the moments up to the third order of a polygon or rasterized shape.

Declaration

public static Moments Moments(IEnumerable<Point> array, bool binaryImage = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	array	Array of 2D points
System.Boolean	binaryImage	If it is true, then all the non-zero image pixels are treated as 1’s

Returns

Type	Description
Moments

Moments(IEnumerable<Point2f>, Boolean)

Calculates all of the moments up to the third order of a polygon or rasterized shape.

Declaration

public static Moments Moments(IEnumerable<Point2f> array, bool binaryImage = false)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	array	Array of 2D points
System.Boolean	binaryImage	If it is true, then all the non-zero image pixels are treated as 1’s

Returns

Type	Description
Moments

Moments(InputArray, Boolean)

Calculates all of the moments up to the third order of a polygon or rasterized shape.

Declaration

public static Moments Moments(InputArray array, bool binaryImage = false)

Parameters

Type	Name	Description
InputArray	array	A raster image (single-channel, 8-bit or floating-point 2D array) or an array ( 1xN or Nx1 ) of 2D points ( Point or Point2f )
System.Boolean	binaryImage	If it is true, then all the non-zero image pixels are treated as 1’s

Returns

Type	Description
Moments

Moments(Byte[,], Boolean)

Calculates all of the moments up to the third order of a polygon or rasterized shape.

Declaration

public static Moments Moments(byte[, ] array, bool binaryImage = false)

Parameters

Type	Name	Description
System.Byte[,]	array	A raster image (8-bit) 2D array
System.Boolean	binaryImage	If it is true, then all the non-zero image pixels are treated as 1’s

Returns

Type	Description
Moments

Moments(Single[,], Boolean)

Calculates all of the moments up to the third order of a polygon or rasterized shape.

Declaration

public static Moments Moments(float[, ] array, bool binaryImage = false)

Parameters

Type	Name	Description
System.Single[,]	array	A raster image (floating-point) 2D array
System.Boolean	binaryImage	If it is true, then all the non-zero image pixels are treated as 1’s

Returns

Type	Description
Moments

MorphologyDefaultBorderValue()

Default borderValue for Dilate/Erode

Declaration

public static Scalar MorphologyDefaultBorderValue()

Returns

Type	Description
OpenCvSharp.Scalar

MorphologyEx(InputArray, OutputArray, MorphTypes, InputArray, Nullable<Point>, Int32, BorderTypes, Nullable<Scalar>)

Performs advanced morphological transformations

Declaration

public static void MorphologyEx(InputArray src, OutputArray dst, MorphTypes op, InputArray element, Point? anchor = null, int iterations = 1, BorderTypes borderType = BorderTypes.Constant, Scalar? borderValue = null)

Parameters

Type	Name	Description
InputArray	src	Source image
OutputArray	dst	Destination image. It will have the same size and the same type as src
MorphTypes	op	Type of morphological operation
InputArray	element	Structuring element
System.Nullable<OpenCvSharp.Point>	anchor	Position of the anchor within the element. The default value (-1, -1) means that the anchor is at the element center
System.Int32	iterations	Number of times erosion and dilation are applied. [By default this is 1]
BorderTypes	borderType	The pixel extrapolation method. [By default this is BorderType.Constant]
System.Nullable<OpenCvSharp.Scalar>	borderValue	The border value in case of a constant border. The default value has a special meaning. [By default this is CvCpp.MorphologyDefaultBorderValue()]

MoveWindow(String, Int32, Int32)

Moves window to the specified position

Declaration

public static void MoveWindow(string winName, int x, int y)

Parameters

Type	Name	Description
System.String	winName	Window name
System.Int32	x	The new x-coordinate of the window
System.Int32	y	The new y-coordinate of the window

MulSpectrums(InputArray, InputArray, OutputArray, DftFlags, Boolean)

Performs the per-element multiplication of two Fourier spectrums.

Declaration

public static void MulSpectrums(InputArray a, InputArray b, OutputArray c, DftFlags flags, bool conjB = false)

Parameters

Type	Name	Description
InputArray	a	first input array.
InputArray	b	second input array of the same size and type as src1.
OutputArray	c	output array of the same size and type as src1.
DftFlags	flags	operation flags; currently, the only supported flag is cv::DFT_ROWS, which indicates that each row of src1 and src2 is an independent 1D Fourier spectrum. If you do not want to use this flag, then simply add a 0 as value.
System.Boolean	conjB	optional flag that conjugates the second input array before the multiplication (true) or not (false).

Multiply(InputArray, InputArray, OutputArray, Double, Int32)

Calculates the per-element scaled product of two arrays

Declaration

public static void Multiply(InputArray src1, InputArray src2, OutputArray dst, double scale = 1, int dtype = -1)

Parameters

Type	Name	Description
InputArray	src1	The first source array
InputArray	src2	The second source array of the same size and the same type as src1
OutputArray	dst	The destination array; will have the same size and the same type as src1
System.Double	scale	The optional scale factor. [By default this is 1]
System.Int32	dtype

MulTransposed(InputArray, OutputArray, Boolean, InputArray, Double, Int32)

multiplies matrix by its transposition from the left or from the right

Declaration

public static void MulTransposed(InputArray src, OutputArray dst, bool aTa, InputArray delta = null, double scale = 1, int dtype = -1)

Parameters

Type	Name	Description
InputArray	src	The source matrix
OutputArray	dst	The destination square matrix
System.Boolean	aTa	Specifies the multiplication ordering; see the description below
InputArray	delta	The optional delta matrix, subtracted from src before the multiplication. When the matrix is empty ( delta=Mat() ), it’s assumed to be zero, i.e. nothing is subtracted, otherwise if it has the same size as src, then it’s simply subtracted, otherwise it is "repeated" to cover the full src and then subtracted. Type of the delta matrix, when it's not empty, must be the same as the type of created destination matrix, see the rtype description
System.Double	scale	The optional scale factor for the matrix product
System.Int32	dtype	When it’s negative, the destination matrix will have the same type as src . Otherwise, it will have type=CV_MAT_DEPTH(rtype), which should be either CV_32F or CV_64F

NamedWindow(String, WindowFlags)

Creates a window.

Declaration

public static void NamedWindow(string winName, WindowFlags flags = WindowFlags.Normal)

Parameters

Type	Name	Description
System.String	winName	Name of the window in the window caption that may be used as a window identifier.
WindowFlags	flags	Flags of the window. Currently the only supported flag is CV WINDOW AUTOSIZE. If this is set, the window size is automatically adjusted to fit the displayed image (see imshow ), and the user can not change the window size manually.

Norm(InputArray, InputArray, NormTypes, InputArray)

computes norm of selected part of the difference between two arrays

Declaration

public static double Norm(InputArray src1, InputArray src2, NormTypes normType = NormTypes.L2, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src1	The first source array
InputArray	src2	The second source array of the same size and the same type as src1
NormTypes	normType	Type of the norm
InputArray	mask	The optional operation mask

Returns

Type	Description
System.Double

Norm(InputArray, NormTypes, InputArray)

Calculates absolute array norm, absolute difference norm, or relative difference norm.

Declaration

public static double Norm(InputArray src1, NormTypes normType = NormTypes.L2, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src1	The first source array
NormTypes	normType	Type of the norm
InputArray	mask	The optional operation mask

Returns

Type	Description
System.Double

Normalize(InputArray, InputOutputArray, Double, Double, NormTypes, Int32, InputArray)

scales and shifts array elements so that either the specified norm (alpha) or the minimum (alpha) and maximum (beta) array values get the specified values

Declaration

public static void Normalize(InputArray src, InputOutputArray dst, double alpha = 1, double beta = 0, NormTypes normType = NormTypes.L2, int dtype = -1, InputArray mask = null)

Parameters

Type	Name	Description
InputArray	src	The source array
InputOutputArray	dst	The destination array; will have the same size as src
System.Double	alpha	The norm value to normalize to or the lower range boundary in the case of range normalization
System.Double	beta	The upper range boundary in the case of range normalization; not used for norm normalization
NormTypes	normType	The normalization type
System.Int32	dtype	When the parameter is negative, the destination array will have the same type as src, otherwise it will have the same number of channels as src and the depth =CV_MAT_DEPTH(rtype)
InputArray	mask	The optional operation mask

Partition<T>(IEnumerable<T>, out Int32[], Cv2.PartitionPredicate<T>)

Splits an element set into equivalency classes. Consider using GroupBy of Linq instead.

Declaration

public static int Partition<T>(IEnumerable<T> vec, out int[] labels, Cv2.PartitionPredicate<T> predicate)

Parameters

Type	Name	Description
IEnumerable<T>	vec	Set of elements stored as a vector.
System.Int32[]	labels	Output vector of labels. It contains as many elements as vec. Each label labels[i] is a 0-based cluster index of vec[i] .
Cv2.PartitionPredicate<T>	predicate	Equivalence predicate (a boolean function of two arguments). The predicate returns true when the elements are certainly in the same class, and returns false if they may or may not be in the same class.

Returns

Type	Description
System.Int32

Type Parameters

Name	Description
T

PatchNaNs(InputOutputArray, Double)

converts NaN's to the given number

Declaration

public static void PatchNaNs(InputOutputArray a, double val = 0)

Parameters

Type	Name	Description
InputOutputArray	a
System.Double	val

PCABackProject(InputArray, InputArray, InputArray, OutputArray)

Reconstructs vectors from their PC projections.

Declaration

public static void PCABackProject(InputArray data, InputArray mean, InputArray eigenvectors, OutputArray result)

Parameters

Type	Name	Description
InputArray	data	input samples stored as the matrix rows or as the matrix columns.
InputArray	mean	optional mean value; if the matrix is empty (noArray()), the mean is computed from the data.
InputArray	eigenvectors	eigenvectors of the covariation matrix
OutputArray	result	output vectors

PCACompute(InputArray, InputOutputArray, OutputArray, OutputArray, Int32)

PCA of the supplied dataset.

Declaration

public static void PCACompute(InputArray data, InputOutputArray mean, OutputArray eigenvectors, OutputArray eigenvalues, int maxComponents = 0)

Parameters

Type	Name	Description
InputArray	data	input samples stored as the matrix rows or as the matrix columns.
InputOutputArray	mean	optional mean value; if the matrix is empty (noArray()), the mean is computed from the data.
OutputArray	eigenvectors	eigenvectors of the covariation matrix
OutputArray	eigenvalues	eigenvalues of the covariation matrix
System.Int32	maxComponents	maximum number of components that PCA should retain; by default, all the components are retained.

PCACompute(InputArray, InputOutputArray, OutputArray, Int32)

PCA of the supplied dataset.

Declaration

public static void PCACompute(InputArray data, InputOutputArray mean, OutputArray eigenvectors, int maxComponents = 0)

Parameters

Type	Name	Description
InputArray	data	input samples stored as the matrix rows or as the matrix columns.
InputOutputArray	mean	optional mean value; if the matrix is empty (noArray()), the mean is computed from the data.
OutputArray	eigenvectors	eigenvectors of the covariation matrix
System.Int32	maxComponents	maximum number of components that PCA should retain; by default, all the components are retained.

PCAComputeVar(InputArray, InputOutputArray, OutputArray, OutputArray, Double)

PCA of the supplied dataset.

Declaration

public static void PCAComputeVar(InputArray data, InputOutputArray mean, OutputArray eigenvectors, OutputArray eigenvalues, double retainedVariance)

Parameters

Type	Name	Description
InputArray	data	input samples stored as the matrix rows or as the matrix columns.
InputOutputArray	mean	optional mean value; if the matrix is empty (noArray()), the mean is computed from the data.
OutputArray	eigenvectors	eigenvectors of the covariation matrix
OutputArray	eigenvalues	eigenvalues of the covariation matrix
System.Double	retainedVariance	Percentage of variance that PCA should retain. Using this parameter will let the PCA decided how many components to retain but it will always keep at least 2.

PCAComputeVar(InputArray, InputOutputArray, OutputArray, Double)

PCA of the supplied dataset.

Declaration

public static void PCAComputeVar(InputArray data, InputOutputArray mean, OutputArray eigenvectors, double retainedVariance)

Parameters

Type	Name	Description
InputArray	data	input samples stored as the matrix rows or as the matrix columns.
InputOutputArray	mean	optional mean value; if the matrix is empty (noArray()), the mean is computed from the data.
OutputArray	eigenvectors	eigenvectors of the covariation matrix
System.Double	retainedVariance	Percentage of variance that PCA should retain. Using this parameter will let the PCA decided how many components to retain but it will always keep at least 2.

PCAProject(InputArray, InputArray, InputArray, OutputArray)

Projects vector(s) to the principal component subspace.

Declaration

public static void PCAProject(InputArray data, InputArray mean, InputArray eigenvectors, OutputArray result)

Parameters

Type	Name	Description
InputArray	data	input samples stored as the matrix rows or as the matrix columns.
InputArray	mean	optional mean value; if the matrix is empty (noArray()), the mean is computed from the data.
InputArray	eigenvectors	eigenvectors of the covariation matrix
OutputArray	result	output vectors

PencilSketch(InputArray, OutputArray, OutputArray, Single, Single, Single)

Pencil-like non-photorealistic line drawing

Declaration

public static void PencilSketch(InputArray src, OutputArray dst1, OutputArray dst2, float sigmaS = 60F, float sigmaR = 0.07F, float shadeFactor = 0.02F)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
OutputArray	dst1	Output 8-bit 1-channel image.
OutputArray	dst2	Output image with the same size and type as src.
System.Single	sigmaS	Range between 0 to 200.
System.Single	sigmaR	Range between 0 to 1.
System.Single	shadeFactor	Range between 0 to 0.1.

PerspectiveTransform(IEnumerable<Point2d>, Mat)

performs perspective transformation of each element of multi-channel input matrix

Declaration

public static Point2d[] PerspectiveTransform(IEnumerable<Point2d> src, Mat m)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2d>	src	The source two-channel or three-channel floating-point array; each element is 2D/3D vector to be transformed
Mat	m	3x3 or 4x4 transformation matrix

Returns

Type	Description
OpenCvSharp.Point2d[]	The destination array; it will have the same size and same type as src

PerspectiveTransform(IEnumerable<Point2f>, Mat)

performs perspective transformation of each element of multi-channel input matrix

Declaration

public static Point2f[] PerspectiveTransform(IEnumerable<Point2f> src, Mat m)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	src	The source two-channel or three-channel floating-point array; each element is 2D/3D vector to be transformed
Mat	m	3x3 or 4x4 transformation matrix

Returns

Type	Description
OpenCvSharp.Point2f[]	The destination array; it will have the same size and same type as src

PerspectiveTransform(IEnumerable<Point3d>, Mat)

performs perspective transformation of each element of multi-channel input matrix

Declaration

public static Point3d[] PerspectiveTransform(IEnumerable<Point3d> src, Mat m)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3d>	src	The source two-channel or three-channel floating-point array; each element is 2D/3D vector to be transformed
Mat	m	3x3 or 4x4 transformation matrix

Returns

Type	Description
OpenCvSharp.Point3d[]	The destination array; it will have the same size and same type as src

PerspectiveTransform(IEnumerable<Point3f>, Mat)

performs perspective transformation of each element of multi-channel input matrix

Declaration

public static Point3f[] PerspectiveTransform(IEnumerable<Point3f> src, Mat m)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3f>	src	The source two-channel or three-channel floating-point array; each element is 2D/3D vector to be transformed
Mat	m	3x3 or 4x4 transformation matrix

Returns

Type	Description
OpenCvSharp.Point3f[]	The destination array; it will have the same size and same type as src

PerspectiveTransform(InputArray, OutputArray, InputArray)

performs perspective transformation of each element of multi-channel input matrix

Declaration

public static void PerspectiveTransform(InputArray src, OutputArray dst, InputArray m)

Parameters

Type	Name	Description
InputArray	src	The source two-channel or three-channel floating-point array; each element is 2D/3D vector to be transformed
OutputArray	dst	The destination array; it will have the same size and same type as src
InputArray	m	3x3 or 4x4 transformation matrix

Phase(InputArray, InputArray, OutputArray, Boolean)

Calculates the rotation angle of 2D vectors.

Declaration

public static void Phase(InputArray x, InputArray y, OutputArray angle, bool angleInDegrees = false)

Parameters

Type	Name	Description
InputArray	x	input floating-point array of x-coordinates of 2D vectors.
InputArray	y	input array of y-coordinates of 2D vectors; it must have the same size and the same type as x.
OutputArray	angle	output array of vector angles; it has the same size and same type as x.
System.Boolean	angleInDegrees	when true, the function calculates the angle in degrees, otherwise, they are measured in radians.

PhaseCorrelate(InputArray, InputArray, InputArray, out Double)

The function is used to detect translational shifts that occur between two images.

The operation takes advantage of the Fourier shift theorem for detecting the translational shift in the frequency domain.It can be used for fast image registration as well as motion estimation. For more information please see http://en.wikipedia.org/wiki/Phase_correlation.

Calculates the cross-power spectrum of two supplied source arrays. The arrays are padded if needed with getOptimalDFTSize.

Declaration

public static Point2d PhaseCorrelate(InputArray src1, InputArray src2, InputArray window, out double response)

Parameters

Type	Name	Description
InputArray	src1	Source floating point array (CV_32FC1 or CV_64FC1)
InputArray	src2	Source floating point array (CV_32FC1 or CV_64FC1)
InputArray	window	Floating point array with windowing coefficients to reduce edge effects (optional).
System.Double	response	Signal power within the 5x5 centroid around the peak, between 0 and 1 (optional).

Returns

Type	Description
OpenCvSharp.Point2d	detected phase shift(sub-pixel) between the two arrays.

PointPolygonTest(IEnumerable<Point>, Point2f, Boolean)

Checks if the point is inside the contour. Optionally computes the signed distance from the point to the contour boundary

Declaration

public static double PointPolygonTest(IEnumerable<Point> contour, Point2f pt, bool measureDist)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point>	contour
OpenCvSharp.Point2f	pt
System.Boolean	measureDist

Returns

Type	Description
System.Double

PointPolygonTest(IEnumerable<Point2f>, Point2f, Boolean)

Checks if the point is inside the contour. Optionally computes the signed distance from the point to the contour boundary.

Declaration

public static double PointPolygonTest(IEnumerable<Point2f> contour, Point2f pt, bool measureDist)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2f>	contour	Input contour.
OpenCvSharp.Point2f	pt	Point tested against the contour.
System.Boolean	measureDist	If true, the function estimates the signed distance from the point to the nearest contour edge. Otherwise, the function only checks if the point is inside a contour or not.

Returns

Type	Description
System.Double	Positive (inside), negative (outside), or zero (on an edge) value.

PointPolygonTest(InputArray, Point2f, Boolean)

Checks if the point is inside the contour. Optionally computes the signed distance from the point to the contour boundary

Declaration

public static double PointPolygonTest(InputArray contour, Point2f pt, bool measureDist)

Parameters

Type	Name	Description
InputArray	contour
OpenCvSharp.Point2f	pt
System.Boolean	measureDist

Returns

Type	Description
System.Double

PolarToCart(InputArray, InputArray, OutputArray, OutputArray, Boolean)

Calculates x and y coordinates of 2D vectors from their magnitude and angle.

Declaration

public static void PolarToCart(InputArray magnitude, InputArray angle, OutputArray x, OutputArray y, bool angleInDegrees = false)

Parameters

Type	Name	Description
InputArray	magnitude	input floating-point array of magnitudes of 2D vectors; it can be an empty matrix(=Mat()), in this case, the function assumes that all the magnitudes are = 1; if it is not empty, it must have the same size and type as angle.
InputArray	angle	input floating-point array of angles of 2D vectors.
OutputArray	x	output array of x-coordinates of 2D vectors; it has the same size and type as angle.
OutputArray	y	output array of y-coordinates of 2D vectors; it has the same size and type as angle.
System.Boolean	angleInDegrees	when true, the input angles are measured in degrees, otherwise, they are measured in radians.

Polylines(InputOutputArray, InputArray, Boolean, Scalar, Int32, LineTypes, Int32)

draws one or more polygonal curves

Declaration

public static void Polylines(InputOutputArray img, InputArray pts, bool isClosed, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img
InputArray	pts
System.Boolean	isClosed
OpenCvSharp.Scalar	color
System.Int32	thickness
LineTypes	lineType
System.Int32	shift

Polylines(Mat, IEnumerable<IEnumerable<Point>>, Boolean, Scalar, Int32, LineTypes, Int32)

draws one or more polygonal curves

Declaration

public static void Polylines(Mat img, IEnumerable<IEnumerable<Point>> pts, bool isClosed, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
Mat	img
IEnumerable<IEnumerable<OpenCvSharp.Point>>	pts
System.Boolean	isClosed
OpenCvSharp.Scalar	color
System.Int32	thickness
LineTypes	lineType
System.Int32	shift

Pow(InputArray, Double, OutputArray)

raises the input matrix elements to the specified power (b = a**power)

Declaration

public static void Pow(InputArray src, double power, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	The source array
System.Double	power	The exponent of power
OutputArray	dst	The destination array; will have the same size and the same type as src

PreCornerDetect(InputArray, OutputArray, Int32, BorderTypes)

computes another complex cornerness criteria at each pixel

Declaration

public static void PreCornerDetect(InputArray src, OutputArray dst, int ksize, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src
OutputArray	dst
System.Int32	ksize
BorderTypes	borderType

ProjectPoints(IEnumerable<Point3f>, Double[], Double[], Double[,], Double[], out Point2f[], out Double[,], Double)

projects points from the model coordinate space to the image coordinates. Also computes derivatives of the image coordinates w.r.t the intrinsic and extrinsic camera parameters

Declaration

public static void ProjectPoints(IEnumerable<Point3f> objectPoints, double[] rvec, double[] tvec, double[, ] cameraMatrix, double[] distCoeffs, out Point2f[] imagePoints, out double[, ] jacobian, double aspectRatio = 0)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3f>	objectPoints	Array of object points, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel, where N is the number of points in the view.
System.Double[]	rvec	Rotation vector (3x1).
System.Double[]	tvec	Translation vector (3x1).
System.Double[,]	cameraMatrix	Camera matrix (3x3)
System.Double[]	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
OpenCvSharp.Point2f[]	imagePoints	Output array of image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel
System.Double[,]	jacobian	Optional output 2Nx(10 + numDistCoeffs) jacobian matrix of derivatives of image points with respect to components of the rotation vector, translation vector, focal lengths, coordinates of the principal point and the distortion coefficients. In the old interface different components of the jacobian are returned via different output parameters.
System.Double	aspectRatio	Optional “fixed aspect ratio” parameter. If the parameter is not 0, the function assumes that the aspect ratio (fx/fy) is fixed and correspondingly adjusts the jacobian matrix.

ProjectPoints(InputArray, InputArray, InputArray, InputArray, InputArray, OutputArray, OutputArray, Double)

projects points from the model coordinate space to the image coordinates. Also computes derivatives of the image coordinates w.r.t the intrinsic and extrinsic camera parameters

Declaration

public static void ProjectPoints(InputArray objectPoints, InputArray rvec, InputArray tvec, InputArray cameraMatrix, InputArray distCoeffs, OutputArray imagePoints, OutputArray jacobian = null, double aspectRatio = 0)

Parameters

Type	Name	Description
InputArray	objectPoints	Array of object points, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel, where N is the number of points in the view.
InputArray	rvec	Rotation vector (3x1).
InputArray	tvec	Translation vector (3x1).
InputArray	cameraMatrix	Camera matrix (3x3)
InputArray	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
OutputArray	imagePoints	Output array of image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel
OutputArray	jacobian	Optional output 2Nx(10 + numDistCoeffs) jacobian matrix of derivatives of image points with respect to components of the rotation vector, translation vector, focal lengths, coordinates of the principal point and the distortion coefficients. In the old interface different components of the jacobian are returned via different output parameters.
System.Double	aspectRatio	Optional “fixed aspect ratio” parameter. If the parameter is not 0, the function assumes that the aspect ratio (fx/fy) is fixed and correspondingly adjusts the jacobian matrix.

PSNR(InputArray, InputArray, Double)

Computes the Peak Signal-to-Noise Ratio (PSNR) image quality metric.

This function calculates the Peak Signal-to-Noise Ratio(PSNR) image quality metric in decibels(dB), between two input arrays src1 and src2.The arrays must have the same type.

Declaration

public static double PSNR(InputArray src1, InputArray src2, double r = 255)

Parameters

Type	Name	Description
InputArray	src1	first input array.
InputArray	src2	second input array of the same size as src1.
System.Double	r	the maximum pixel value (255 by default)

Returns

Type	Description
System.Double

PutText(InputOutputArray, String, Point, HersheyFonts, Double, Scalar, Int32, LineTypes, Boolean)

renders text string in the image

Declaration

public static void PutText(InputOutputArray img, string text, Point org, HersheyFonts fontFace, double fontScale, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, bool bottomLeftOrigin = false)

Parameters

Type	Name	Description
InputOutputArray	img	Image.
System.String	text	Text string to be drawn.
OpenCvSharp.Point	org	Bottom-left corner of the text string in the image.
HersheyFonts	fontFace	Font type, see #HersheyFonts.
System.Double	fontScale	Font scale factor that is multiplied by the font-specific base size.
OpenCvSharp.Scalar	color	Text color.
System.Int32	thickness	Thickness of the lines used to draw a text.
LineTypes	lineType	Line type. See #LineTypes
System.Boolean	bottomLeftOrigin	When true, the image data origin is at the bottom-left corner. Otherwise, it is at the top-left corner.

PyrDown(InputArray, OutputArray, Nullable<Size>, BorderTypes)

Blurs an image and downsamples it.

Declaration

public static void PyrDown(InputArray src, OutputArray dst, Size? dstSize = null, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	input image.
OutputArray	dst	output image; it has the specified size and the same type as src.
System.Nullable<OpenCvSharp.Size>	dstSize	size of the output image; by default, it is computed as Size((src.cols+1)/2
BorderTypes	borderType

PyrMeanShiftFiltering(InputArray, OutputArray, Double, Double, Int32, Nullable<TermCriteria>)

Performs initial step of meanshift segmentation of an image.

Declaration

public static void PyrMeanShiftFiltering(InputArray src, OutputArray dst, double sp, double sr, int maxLevel = 1, TermCriteria? termcrit = null)

Parameters

Type	Name	Description
InputArray	src	The source 8-bit, 3-channel image.
OutputArray	dst	The destination image of the same format and the same size as the source.
System.Double	sp	The spatial window radius.
System.Double	sr	The color window radius.
System.Int32	maxLevel	Maximum level of the pyramid for the segmentation.
System.Nullable<OpenCvSharp.TermCriteria>	termcrit	Termination criteria: when to stop meanshift iterations.

PyrUp(InputArray, OutputArray, Nullable<Size>, BorderTypes)

Upsamples an image and then blurs it.

Declaration

public static void PyrUp(InputArray src, OutputArray dst, Size? dstSize = null, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	input image.
OutputArray	dst	output image. It has the specified size and the same type as src.
System.Nullable<OpenCvSharp.Size>	dstSize	size of the output image; by default, it is computed as Size(src.cols2, (src.rows2)
BorderTypes	borderType

Randn(InputOutputArray, InputArray, InputArray)

fills array with normally-distributed random numbers with the specified mean and the standard deviation

Declaration

public static void Randn(InputOutputArray dst, InputArray mean, InputArray stddev)

Parameters

Type	Name	Description
InputOutputArray	dst	The output array of random numbers. The array must be pre-allocated and have 1 to 4 channels
InputArray	mean	The mean value (expectation) of the generated random numbers
InputArray	stddev	The standard deviation of the generated random numbers

Randn(InputOutputArray, Scalar, Scalar)

fills array with normally-distributed random numbers with the specified mean and the standard deviation

Declaration

public static void Randn(InputOutputArray dst, Scalar mean, Scalar stddev)

Parameters

Type	Name	Description
InputOutputArray	dst	The output array of random numbers. The array must be pre-allocated and have 1 to 4 channels
OpenCvSharp.Scalar	mean	The mean value (expectation) of the generated random numbers
OpenCvSharp.Scalar	stddev	The standard deviation of the generated random numbers

RandShuffle(InputOutputArray, Double)

shuffles the input array elements

Declaration

public static void RandShuffle(InputOutputArray dst, double iterFactor)

Parameters

Type	Name	Description
InputOutputArray	dst	The input/output numerical 1D array
System.Double	iterFactor	The scale factor that determines the number of random swap operations.

RandShuffle(InputOutputArray, Double, ref RNG)

shuffles the input array elements

Declaration

public static void RandShuffle(InputOutputArray dst, double iterFactor, ref RNG rng)

Parameters

Type	Name	Description
InputOutputArray	dst	The input/output numerical 1D array
System.Double	iterFactor	The scale factor that determines the number of random swap operations.
RNG	rng	The optional random number generator used for shuffling. If it is null, theRng() is used instead.

Randu(InputOutputArray, InputArray, InputArray)

fills array with uniformly-distributed random numbers from the range [low, high)

Declaration

public static void Randu(InputOutputArray dst, InputArray low, InputArray high)

Parameters

Type	Name	Description
InputOutputArray	dst	The output array of random numbers. The array must be pre-allocated and have 1 to 4 channels
InputArray	low	The inclusive lower boundary of the generated random numbers
InputArray	high	The exclusive upper boundary of the generated random numbers

Randu(InputOutputArray, Scalar, Scalar)

fills array with uniformly-distributed random numbers from the range [low, high)

Declaration

public static void Randu(InputOutputArray dst, Scalar low, Scalar high)

Parameters

Type	Name	Description
InputOutputArray	dst	The output array of random numbers. The array must be pre-allocated and have 1 to 4 channels
OpenCvSharp.Scalar	low	The inclusive lower boundary of the generated random numbers
OpenCvSharp.Scalar	high	The exclusive upper boundary of the generated random numbers

RecoverPose(InputArray, InputArray, InputArray, InputArray, OutputArray, OutputArray, InputOutputArray)

Recover relative camera rotation and translation from an estimated essential matrix and the corresponding points in two images, using cheirality check. Returns the number of inliers which pass the check.

Declaration

public static int RecoverPose(InputArray E, InputArray points1, InputArray points2, InputArray cameraMatrix, OutputArray R, OutputArray t, InputOutputArray mask = null)

Parameters

Type	Name	Description
InputArray	E	The input essential matrix.
InputArray	points1	Array of N 2D points from the first image. The point coordinates should be floating-point (single or double precision).
InputArray	points2	Array of the second image points of the same size and format as points1.
InputArray	cameraMatrix	Camera matrix K=⎡⎣⎢fx000fy0cxcy1⎤⎦⎥ . Note that this function assumes that points1 and points2 are feature points from cameras with the same camera matrix.
OutputArray	R	Recovered relative rotation.
OutputArray	t	Recovered relative translation.
InputOutputArray	mask	Input/output mask for inliers in points1 and points2. : If it is not empty, then it marks inliers in points1 and points2 for then given essential matrix E. Only these inliers will be used to recover pose. In the output mask only inliers which pass the cheirality check. This function decomposes an essential matrix using decomposeEssentialMat and then verifies possible pose hypotheses by doing cheirality check. The cheirality check basically means that the triangulated 3D points should have positive depth.

Returns

Type	Description
System.Int32

RecoverPose(InputArray, InputArray, InputArray, InputArray, OutputArray, OutputArray, Double, InputOutputArray, OutputArray)

Recover relative camera rotation and translation from an estimated essential matrix and the corresponding points in two images, using cheirality check. Returns the number of inliers which pass the check.

Declaration

public static int RecoverPose(InputArray E, InputArray points1, InputArray points2, InputArray cameraMatrix, OutputArray R, OutputArray t, double distanceTresh, InputOutputArray mask = null, OutputArray triangulatedPoints = null)

Parameters

Type	Name	Description
InputArray	E	The input essential matrix.
InputArray	points1	Array of N 2D points from the first image. The point coordinates should be floating-point (single or double precision).
InputArray	points2	Array of the second image points of the same size and format as points1.
InputArray	cameraMatrix	Camera matrix K=⎡⎣⎢fx000fy0cxcy1⎤⎦⎥ . Note that this function assumes that points1 and points2 are feature points from cameras with the same camera matrix.
OutputArray	R	Recovered relative rotation.
OutputArray	t	Recovered relative translation.
System.Double	distanceTresh	threshold distance which is used to filter out far away points (i.e. infinite points).
InputOutputArray	mask	Input/output mask for inliers in points1 and points2. : If it is not empty, then it marks inliers in points1 and points2 for then given essential matrix E. Only these inliers will be used to recover pose. In the output mask only inliers which pass the cheirality check. This function decomposes an essential matrix using decomposeEssentialMat and then verifies possible pose hypotheses by doing cheirality check. The cheirality check basically means that the triangulated 3D points should have positive depth.
OutputArray	triangulatedPoints	3d points which were reconstructed by triangulation.

Returns

Type	Description
System.Int32

RecoverPose(InputArray, InputArray, InputArray, OutputArray, OutputArray, Double, Point2d, InputOutputArray)

Recover relative camera rotation and translation from an estimated essential matrix and the corresponding points in two images, using cheirality check. Returns the number of inliers which pass the check.

Declaration

public static int RecoverPose(InputArray E, InputArray points1, InputArray points2, OutputArray R, OutputArray t, double focal, Point2d pp, InputOutputArray mask = null)

Parameters

Type	Name	Description
InputArray	E	The input essential matrix.
InputArray	points1	Array of N 2D points from the first image. The point coordinates should be floating-point (single or double precision).
InputArray	points2	Array of the second image points of the same size and format as points1.
OutputArray	R	Recovered relative rotation.
OutputArray	t	Recovered relative translation.
System.Double	focal	Focal length of the camera. Note that this function assumes that points1 and points2 are feature points from cameras with same focal length and principal point.
OpenCvSharp.Point2d	pp	principal point of the camera.
InputOutputArray	mask	Input/output mask for inliers in points1 and points2. : If it is not empty, then it marks inliers in points1 and points2 for then given essential matrix E. Only these inliers will be used to recover pose. In the output mask only inliers which pass the cheirality check. This function decomposes an essential matrix using decomposeEssentialMat and then verifies possible pose hypotheses by doing cheirality check. The cheirality check basically means that the triangulated 3D points should have positive depth.

Returns

Type	Description
System.Int32

Rectangle(InputOutputArray, Point, Point, Scalar, Int32, LineTypes, Int32)

Draws simple, thick or filled rectangle

Declaration

public static void Rectangle(InputOutputArray img, Point pt1, Point pt2, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	Image.
OpenCvSharp.Point	pt1	One of the rectangle vertices.
OpenCvSharp.Point	pt2	Opposite rectangle vertex.
OpenCvSharp.Scalar	color	Line color (RGB) or brightness (grayscale image).
System.Int32	thickness	Thickness of lines that make up the rectangle. Negative values make the function to draw a filled rectangle. [By default this is 1]
LineTypes	lineType	Type of the line, see cvLine description. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the point coordinates. [By default this is 0]

Rectangle(InputOutputArray, Rect, Scalar, Int32, LineTypes, Int32)

Draws simple, thick or filled rectangle

Declaration

public static void Rectangle(InputOutputArray img, Rect rect, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
InputOutputArray	img	Image.
OpenCvSharp.Rect	rect	Rectangle.
OpenCvSharp.Scalar	color	Line color (RGB) or brightness (grayscale image).
System.Int32	thickness	Thickness of lines that make up the rectangle. Negative values make the function to draw a filled rectangle. [By default this is 1]
LineTypes	lineType	Type of the line, see cvLine description. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the point coordinates. [By default this is 0]

Rectangle(Mat, Point, Point, Scalar, Int32, LineTypes, Int32)

Draws simple, thick or filled rectangle

Declaration

public static void Rectangle(Mat img, Point pt1, Point pt2, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
Mat	img	Image.
OpenCvSharp.Point	pt1	One of the rectangle vertices.
OpenCvSharp.Point	pt2	Opposite rectangle vertex.
OpenCvSharp.Scalar	color	Line color (RGB) or brightness (grayscale image).
System.Int32	thickness	Thickness of lines that make up the rectangle. Negative values make the function to draw a filled rectangle. [By default this is 1]
LineTypes	lineType	Type of the line, see cvLine description. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the point coordinates. [By default this is 0]

Rectangle(Mat, Rect, Scalar, Int32, LineTypes, Int32)

Draws simple, thick or filled rectangle

Declaration

public static void Rectangle(Mat img, Rect rect, Scalar color, int thickness = 1, LineTypes lineType = LineTypes.Link8, int shift = 0)

Parameters

Type	Name	Description
Mat	img	Image.
OpenCvSharp.Rect	rect	Rectangle.
OpenCvSharp.Scalar	color	Line color (RGB) or brightness (grayscale image).
System.Int32	thickness	Thickness of lines that make up the rectangle. Negative values make the function to draw a filled rectangle. [By default this is 1]
LineTypes	lineType	Type of the line, see cvLine description. [By default this is LineType.Link8]
System.Int32	shift	Number of fractional bits in the point coordinates. [By default this is 0]

Rectify3Collinear(InputArray, InputArray, InputArray, InputArray, InputArray, InputArray, IEnumerable<InputArray>, IEnumerable<InputArray>, Size, InputArray, InputArray, InputArray, InputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, Double, Size, out Rect, out Rect, StereoRectificationFlags)

computes the rectification transformations for 3-head camera, where all the heads are on the same line.

Declaration

public static float Rectify3Collinear(InputArray cameraMatrix1, InputArray distCoeffs1, InputArray cameraMatrix2, InputArray distCoeffs2, InputArray cameraMatrix3, InputArray distCoeffs3, IEnumerable<InputArray> imgpt1, IEnumerable<InputArray> imgpt3, Size imageSize, InputArray R12, InputArray T12, InputArray R13, InputArray T13, OutputArray R1, OutputArray R2, OutputArray R3, OutputArray P1, OutputArray P2, OutputArray P3, OutputArray Q, double alpha, Size newImgSize, out Rect roi1, out Rect roi2, StereoRectificationFlags flags)

Parameters

Type	Name	Description
InputArray	cameraMatrix1
InputArray	distCoeffs1
InputArray	cameraMatrix2
InputArray	distCoeffs2
InputArray	cameraMatrix3
InputArray	distCoeffs3
IEnumerable<InputArray>	imgpt1
IEnumerable<InputArray>	imgpt3
OpenCvSharp.Size	imageSize
InputArray	R12
InputArray	T12
InputArray	R13
InputArray	T13
OutputArray	R1
OutputArray	R2
OutputArray	R3
OutputArray	P1
OutputArray	P2
OutputArray	P3
OutputArray	Q
System.Double	alpha
OpenCvSharp.Size	newImgSize
OpenCvSharp.Rect	roi1
OpenCvSharp.Rect	roi2
StereoRectificationFlags	flags

Returns

Type	Description
System.Single

Reduce(InputArray, OutputArray, ReduceDimension, ReduceTypes, Int32)

transforms 2D matrix to 1D row or column vector by taking sum, minimum, maximum or mean value over all the rows

Declaration

public static void Reduce(InputArray src, OutputArray dst, ReduceDimension dim, ReduceTypes rtype, int dtype)

Parameters

Type	Name	Description
InputArray	src	The source 2D matrix
OutputArray	dst	The destination vector. Its size and type is defined by dim and dtype parameters
ReduceDimension	dim	The dimension index along which the matrix is reduced. 0 means that the matrix is reduced to a single row and 1 means that the matrix is reduced to a single column
ReduceTypes	rtype
System.Int32	dtype	When it is negative, the destination vector will have the same type as the source matrix, otherwise, its type will be CV_MAKE_TYPE(CV_MAT_DEPTH(dtype), mtx.channels())

ReduceArgMax(InputArray, OutputArray, Int32, Boolean)

Finds indices of max elements along provided axis

Declaration

public static void ReduceArgMax(InputArray src, OutputArray dst, int axis, bool lastIndex = false)

Parameters

Type	Name	Description
InputArray	src	Input single-channel array
OutputArray	dst	Output array of type CV_32SC1 with the same dimensionality as src, except for axis being reduced - it should be set to 1.
System.Int32	axis	Axis to reduce along
System.Boolean	lastIndex	Whether to get the index of first or last occurrence of max

ReduceArgMin(InputArray, OutputArray, Int32, Boolean)

Finds indices of min elements along provided axis

Declaration

public static void ReduceArgMin(InputArray src, OutputArray dst, int axis, bool lastIndex = false)

Parameters

Type	Name	Description
InputArray	src	Input single-channel array
OutputArray	dst	Output array of type CV_32SC1 with the same dimensionality as src, except for axis being reduced - it should be set to 1.
System.Int32	axis	Axis to reduce along
System.Boolean	lastIndex	Whether to get the index of first or last occurrence of min

Remap(InputArray, OutputArray, InputArray, InputArray, InterpolationFlags, BorderTypes, Nullable<Scalar>)

Applies a generic geometrical transformation to an image.

Declaration

public static void Remap(InputArray src, OutputArray dst, InputArray map1, InputArray map2, InterpolationFlags interpolation = InterpolationFlags.Linear, BorderTypes borderMode = BorderTypes.Constant, Scalar? borderValue = null)

Parameters

Type	Name	Description
InputArray	src	Source image.
OutputArray	dst	Destination image. It has the same size as map1 and the same type as src
InputArray	map1	The first map of either (x,y) points or just x values having the type CV_16SC2, CV_32FC1, or CV_32FC2.
InputArray	map2	The second map of y values having the type CV_16UC1, CV_32FC1, or none (empty map if map1 is (x,y) points), respectively.
InterpolationFlags	interpolation	Interpolation method. The method INTER_AREA is not supported by this function.
BorderTypes	borderMode	Pixel extrapolation method. When borderMode=BORDER_TRANSPARENT, it means that the pixels in the destination image that corresponds to the "outliers" in the source image are not modified by the function.
System.Nullable<OpenCvSharp.Scalar>	borderValue	Value used in case of a constant border. By default, it is 0.

Repeat(InputArray, Int32, Int32, OutputArray)

replicates the input matrix the specified number of times in the horizontal and/or vertical direction

Declaration

public static void Repeat(InputArray src, int ny, int nx, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	The source array to replicate
System.Int32	ny	How many times the src is repeated along the vertical axis
System.Int32	nx	How many times the src is repeated along the horizontal axis
OutputArray	dst	The destination array; will have the same type as src

Repeat(Mat, Int32, Int32)

replicates the input matrix the specified number of times in the horizontal and/or vertical direction

Declaration

public static Mat Repeat(Mat src, int ny, int nx)

Parameters

Type	Name	Description
Mat	src	The source array to replicate
System.Int32	ny	How many times the src is repeated along the vertical axis
System.Int32	nx	How many times the src is repeated along the horizontal axis

Returns

Type	Description
Mat

ReprojectImageTo3D(InputArray, OutputArray, InputArray, Boolean, Int32)

reprojects disparity image to 3D: (x,y,d)->(X,Y,Z) using the matrix Q returned by cv::stereoRectify

Declaration

public static void ReprojectImageTo3D(InputArray disparity, OutputArray _3dImage, InputArray Q, bool handleMissingValues = false, int ddepth = -1)

Parameters

Type	Name	Description
InputArray	disparity	Input single-channel 8-bit unsigned, 16-bit signed, 32-bit signed or 32-bit floating-point disparity image.
OutputArray	_3dImage	Output 3-channel floating-point image of the same size as disparity. Each element of _3dImage(x,y) contains 3D coordinates of the point (x,y) computed from the disparity map.
InputArray	Q	4 x 4 perspective transformation matrix that can be obtained with stereoRectify().
System.Boolean	handleMissingValues	Indicates, whether the function should handle missing values (i.e. points where the disparity was not computed). If handleMissingValues=true, then pixels with the minimal disparity that corresponds to the outliers (see StereoBM::operator() ) are transformed to 3D points with a very large Z value (currently set to 10000).
System.Int32	ddepth	he optional output array depth. If it is -1, the output image will have CV_32F depth. ddepth can also be set to CV_16S, CV_32S or CV_32F.

Resize(InputArray, OutputArray, Size, Double, Double, InterpolationFlags)

Resizes an image.

Declaration

public static void Resize(InputArray src, OutputArray dst, Size dsize, double fx = 0, double fy = 0, InterpolationFlags interpolation = InterpolationFlags.Linear)

Parameters

Type	Name	Description
InputArray	src	input image.
OutputArray	dst	output image; it has the size dsize (when it is non-zero) or the size computed from src.size(), fx, and fy; the type of dst is the same as of src.
OpenCvSharp.Size	dsize	output image size; if it equals zero, it is computed as: dsize = Size(round(fxsrc.cols), round(fysrc.rows)) Either dsize or both fx and fy must be non-zero.
System.Double	fx	scale factor along the horizontal axis; when it equals 0, it is computed as: (double)dsize.width/src.cols
System.Double	fy	scale factor along the vertical axis; when it equals 0, it is computed as: (double)dsize.height/src.rows
InterpolationFlags	interpolation	interpolation method

ResizeWindow(String, Size)

Resizes window to the specified size

Declaration

public static void ResizeWindow(string winName, Size size)

Parameters

Type	Name	Description
System.String	winName	Window name
OpenCvSharp.Size	size	The new window size

ResizeWindow(String, Int32, Int32)

Resizes window to the specified size

Declaration

public static void ResizeWindow(string winName, int width, int height)

Parameters

Type	Name	Description
System.String	winName	Window name
System.Int32	width	The new window width
System.Int32	height	The new window height

Rodrigues(InputArray, OutputArray, OutputArray)

converts rotation vector to rotation matrix or vice versa using Rodrigues transformation

Declaration

public static void Rodrigues(InputArray src, OutputArray dst, OutputArray jacobian = null)

Parameters

Type	Name	Description
InputArray	src	Input rotation vector (3x1 or 1x3) or rotation matrix (3x3).
OutputArray	dst	Output rotation matrix (3x3) or rotation vector (3x1 or 1x3), respectively.
OutputArray	jacobian	Optional output Jacobian matrix, 3x9 or 9x3, which is a matrix of partial derivatives of the output array components with respect to the input array components.

Rodrigues(Double[], out Double[,], out Double[,])

converts rotation vector to rotation matrix using Rodrigues transformation

Declaration

public static void Rodrigues(double[] vector, out double[, ] matrix, out double[, ] jacobian)

Parameters

Type	Name	Description
System.Double[]	vector	Input rotation vector (3x1).
System.Double[,]	matrix	Output rotation matrix (3x3).
System.Double[,]	jacobian	Optional output Jacobian matrix, 3x9, which is a matrix of partial derivatives of the output array components with respect to the input array components.

Rodrigues(Double[,], out Double[], out Double[,])

converts rotation matrix to rotation vector using Rodrigues transformation

Declaration

public static void Rodrigues(double[, ] matrix, out double[] vector, out double[, ] jacobian)

Parameters

Type	Name	Description
System.Double[,]	matrix	Input rotation matrix (3x3).
System.Double[]	vector	Output rotation vector (3x1).
System.Double[,]	jacobian	Optional output Jacobian matrix, 3x9, which is a matrix of partial derivatives of the output array components with respect to the input array components.

Rotate(InputArray, OutputArray, RotateFlags)

Rotates a 2D array in multiples of 90 degrees.

Declaration

public static void Rotate(InputArray src, OutputArray dst, RotateFlags rotateCode)

Parameters

Type	Name	Description
InputArray	src	input array.
OutputArray	dst	output array of the same type as src. The size is the same with ROTATE_180, and the rows and cols are switched for ROTATE_90_CLOCKWISE and ROTATE_90_COUNTERCLOCKWISE.
RotateFlags	rotateCode	an enum to specify how to rotate the array.

RotatedRectangleIntersection(RotatedRect, RotatedRect, OutputArray)

Finds out if there is any intersection between two rotated rectangles. If there is then the vertices of the interesecting region are returned as well. Below are some examples of intersection configurations. The hatched pattern indicates the intersecting region and the red vertices are returned by the function.

Declaration

public static RectanglesIntersectTypes RotatedRectangleIntersection(RotatedRect rect1, RotatedRect rect2, OutputArray intersectingRegion)

Parameters

Type	Name	Description
OpenCvSharp.RotatedRect	rect1	First rectangle
OpenCvSharp.RotatedRect	rect2	Second rectangle
OutputArray	intersectingRegion	The output array of the verticies of the intersecting region. It returns at most 8 vertices. Stored as std::vector<cv::Point2f> or cv::Mat as Mx1 of type CV_32FC2.

Returns

Type	Description
RectanglesIntersectTypes

RotatedRectangleIntersection(RotatedRect, RotatedRect, out Point2f[])

Finds out if there is any intersection between two rotated rectangles. If there is then the vertices of the interesecting region are returned as well. Below are some examples of intersection configurations. The hatched pattern indicates the intersecting region and the red vertices are returned by the function.

Declaration

public static RectanglesIntersectTypes RotatedRectangleIntersection(RotatedRect rect1, RotatedRect rect2, out Point2f[] intersectingRegion)

Parameters

Type	Name	Description
OpenCvSharp.RotatedRect	rect1	First rectangle
OpenCvSharp.RotatedRect	rect2	Second rectangle
OpenCvSharp.Point2f[]	intersectingRegion	The output array of the verticies of the intersecting region. It returns at most 8 vertices.

Returns

Type	Description
RectanglesIntersectTypes

RQDecomp3x3(InputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray)

Computes RQ decomposition of 3x3 matrix

Declaration

public static Vec3d RQDecomp3x3(InputArray src, OutputArray mtxR, OutputArray mtxQ, OutputArray qx = null, OutputArray qy = null, OutputArray qz = null)

Parameters

Type	Name	Description
InputArray	src	3x3 input matrix.
OutputArray	mtxR	Output 3x3 upper-triangular matrix.
OutputArray	mtxQ	Output 3x3 orthogonal matrix.
OutputArray	qx	Optional output 3x3 rotation matrix around x-axis.
OutputArray	qy	Optional output 3x3 rotation matrix around y-axis.
OutputArray	qz	Optional output 3x3 rotation matrix around z-axis.

Returns

Type	Description
Vec3d

RQDecomp3x3(Double[,], out Double[,], out Double[,])

Computes RQ decomposition of 3x3 matrix

Declaration

public static Vec3d RQDecomp3x3(double[, ] src, out double[, ] mtxR, out double[, ] mtxQ)

Parameters

Type	Name	Description
System.Double[,]	src	3x3 input matrix.
System.Double[,]	mtxR	Output 3x3 upper-triangular matrix.
System.Double[,]	mtxQ	Output 3x3 orthogonal matrix.

Returns

Type	Description
Vec3d

RQDecomp3x3(Double[,], out Double[,], out Double[,], out Double[,], out Double[,], out Double[,])

Computes RQ decomposition of 3x3 matrix

Declaration

public static Vec3d RQDecomp3x3(double[, ] src, out double[, ] mtxR, out double[, ] mtxQ, out double[, ] qx, out double[, ] qy, out double[, ] qz)

Parameters

Type	Name	Description
System.Double[,]	src	3x3 input matrix.
System.Double[,]	mtxR	Output 3x3 upper-triangular matrix.
System.Double[,]	mtxQ	Output 3x3 orthogonal matrix.
System.Double[,]	qx	Optional output 3x3 rotation matrix around x-axis.
System.Double[,]	qy	Optional output 3x3 rotation matrix around y-axis.
System.Double[,]	qz	Optional output 3x3 rotation matrix around z-axis.

Returns

Type	Description
Vec3d

SampsonDistance(InputArray, InputArray, InputArray)

Calculates the Sampson Distance between two points.

Declaration

public static double SampsonDistance(InputArray pt1, InputArray pt2, InputArray f)

Parameters

Type	Name	Description
InputArray	pt1	first homogeneous 2d point
InputArray	pt2	second homogeneous 2d point
InputArray	f	F fundamental matrix

Returns

Type	Description
System.Double	The computed Sampson distance.

Remarks

https://github.com/opencv/opencv/blob/master/modules/calib3d/src/fundam.cpp#L1109

SampsonDistance(Point3d, Point3d, Double[,])

Calculates the Sampson Distance between two points.

Declaration

public static double SampsonDistance(Point3d pt1, Point3d pt2, double[, ] f)

Parameters

Type	Name	Description
OpenCvSharp.Point3d	pt1	first homogeneous 2d point
OpenCvSharp.Point3d	pt2	second homogeneous 2d point
System.Double[,]	f	F fundamental matrix

Returns

Type	Description
System.Double	The computed Sampson distance.

Remarks

https://github.com/opencv/opencv/blob/master/modules/calib3d/src/fundam.cpp#L1109

ScaleAdd(InputArray, Double, InputArray, OutputArray)

adds scaled array to another one (dst = alpha*src1 + src2)

Declaration

public static void ScaleAdd(InputArray src1, double alpha, InputArray src2, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src1
System.Double	alpha
InputArray	src2
OutputArray	dst

Scharr(InputArray, OutputArray, MatType, Int32, Int32, Double, Double, BorderTypes)

Calculates the first x- or y- image derivative using Scharr operator

Declaration

public static void Scharr(InputArray src, OutputArray dst, MatType ddepth, int xorder, int yorder, double scale = 1, double delta = 0, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image; will have the same size and the same number of channels as src
OpenCvSharp.MatType	ddepth	The destination image depth
System.Int32	xorder	Order of the derivative x
System.Int32	yorder	Order of the derivative y
System.Double	scale	The optional scale factor for the computed derivative values (by default, no scaling is applie
System.Double	delta	The optional delta value, added to the results prior to storing them in dst
BorderTypes	borderType	The pixel extrapolation method

SeamlessClone(InputArray, InputArray, InputArray, Point, OutputArray, SeamlessCloneMethods)

Image editing tasks concern either global changes (color/intensity corrections, filters, deformations) or local changes concerned to a selection. Here we are interested in achieving local changes, ones that are restricted to a region manually selected (ROI), in a seamless and effortless manner. The extent of the changes ranges from slight distortions to complete replacement by novel content @cite PM03 .

Declaration

public static void SeamlessClone(InputArray src, InputArray dst, InputArray mask, Point p, OutputArray blend, SeamlessCloneMethods flags)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
InputArray	dst	Input 8-bit 3-channel image.
InputArray	mask	Input 8-bit 1 or 3-channel image.
OpenCvSharp.Point	p	Point in dst image where object is placed.
OutputArray	blend	Output image with the same size and type as dst.
SeamlessCloneMethods	flags	Cloning method

SelectROI(InputArray, Boolean, Boolean)

Selects ROI on the given image. Function creates a window and allows user to select a ROI using mouse. Controls: use space or enter to finish selection, use key c to cancel selection (function will return the zero cv::Rect).

Declaration

public static Rect SelectROI(InputArray img, bool showCrosshair = true, bool fromCenter = false)

Parameters

Type	Name	Description
InputArray	img	image to select a ROI.
System.Boolean	showCrosshair	if true crosshair of selection rectangle will be shown.
System.Boolean	fromCenter	if true center of selection will match initial mouse position. In opposite case a corner of selection rectangle will correspond to the initial mouse position.

Returns

Type	Description
OpenCvSharp.Rect	selected ROI or empty rect if selection canceled.

SelectROI(String, InputArray, Boolean, Boolean)

Selects ROI on the given image. Function creates a window and allows user to select a ROI using mouse. Controls: use space or enter to finish selection, use key c to cancel selection (function will return the zero cv::Rect).

Declaration

public static Rect SelectROI(string windowName, InputArray img, bool showCrosshair = true, bool fromCenter = false)

Parameters

Type	Name	Description
System.String	windowName	name of the window where selection process will be shown.
InputArray	img	image to select a ROI.
System.Boolean	showCrosshair	if true crosshair of selection rectangle will be shown.
System.Boolean	fromCenter	if true center of selection will match initial mouse position. In opposite case a corner of selection rectangle will correspond to the initial mouse position.

Returns

Type	Description
OpenCvSharp.Rect	selected ROI or empty rect if selection canceled.

SelectROIs(String, InputArray, Boolean, Boolean)

Selects ROIs on the given image. Function creates a window and allows user to select a ROIs using mouse. Controls: use space or enter to finish current selection and start a new one, use esc to terminate multiple ROI selection process.

Declaration

public static Rect[] SelectROIs(string windowName, InputArray img, bool showCrosshair = true, bool fromCenter = false)

Parameters

Type	Name	Description
System.String	windowName	name of the window where selection process will be shown.
InputArray	img	image to select a ROI.
System.Boolean	showCrosshair	if true crosshair of selection rectangle will be shown.
System.Boolean	fromCenter	if true center of selection will match initial mouse position. In opposite case a corner of selection rectangle will correspond to the initial mouse position.

Returns

Type	Description
OpenCvSharp.Rect[]	selected ROIs.

SepFilter2D(InputArray, OutputArray, MatType, InputArray, InputArray, Nullable<Point>, Double, BorderTypes)

Applies separable linear filter to an image

Declaration

public static void SepFilter2D(InputArray src, OutputArray dst, MatType ddepth, InputArray kernelX, InputArray kernelY, Point? anchor = null, double delta = 0, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image; will have the same size and the same number of channels as src
OpenCvSharp.MatType	ddepth	The destination image depth
InputArray	kernelX	The coefficients for filtering each row
InputArray	kernelY	The coefficients for filtering each column
System.Nullable<OpenCvSharp.Point>	anchor	The anchor position within the kernel; The default value (-1, 1) means that the anchor is at the kernel center
System.Double	delta	The value added to the filtered results before storing them
BorderTypes	borderType	The pixel extrapolation method

SetBreakOnError(Boolean)

Sets/resets the break-on-error mode. When the break-on-error mode is set, the default error handler issues a hardware exception, which can make debugging more convenient.

Declaration

public static bool SetBreakOnError(bool flag)

Parameters

Type	Name	Description
System.Boolean	flag

Returns

Type	Description
System.Boolean	the previous state

SetIdentity(InputOutputArray, Nullable<Scalar>)

initializes scaled identity matrix

Declaration

public static void SetIdentity(InputOutputArray mtx, Scalar? s = null)

Parameters

Type	Name	Description
InputOutputArray	mtx	The matrix to initialize (not necessarily square)
System.Nullable<OpenCvSharp.Scalar>	s	The value to assign to the diagonal elements

SetLogLevel(LogLevel)

Set global logging level

Declaration

public static LogLevel SetLogLevel(LogLevel logLevel)

Parameters

Type	Name	Description
LogLevel	logLevel	logging level

Returns

Type	Description
LogLevel	previous logging level

SetMouseCallback(String, MouseCallback, IntPtr)

Sets the callback function for mouse events occuring within the specified window.

Declaration

public static void SetMouseCallback(string windowName, MouseCallback onMouse, IntPtr userData = null)

Parameters

Type	Name	Description
System.String	windowName	Name of the window.
MouseCallback	onMouse	Reference to the function to be called every time mouse event occurs in the specified window.
IntPtr	userData

SetNumThreads(Int32)

OpenCV will try to set the number of threads for the next parallel region. If threads == 0, OpenCV will disable threading optimizations and run all it's functions sequentially.Passing threads < 0 will reset threads number to system default. This function must be called outside of parallel region. OpenCV will try to run its functions with specified threads number, but some behaviour differs from framework:

• TBB - User-defined parallel constructions will run with the same threads number, if another is not specified.If later on user creates his own scheduler, OpenCV will use it.
• OpenMP - No special defined behaviour.
• Concurrency - If threads == 1, OpenCV will disable threading optimizations and run its functions sequentially.
• GCD - Supports only values <= 0.
• C= - No special defined behaviour.

Declaration

public static void SetNumThreads(int nThreads)

Parameters

Type	Name	Description
System.Int32	nThreads	Number of threads used by OpenCV.

SetTheRNG(UInt64)

Sets the thread-local Random number generator

Declaration

public static RNG SetTheRNG(ulong state)

Parameters

Type	Name	Description
System.UInt64	state

Returns

Type	Description
RNG

SetTrackbarMax(String, String, Int32)

Sets the trackbar maximum position. The function sets the maximum position of the specified trackbar in the specified window.

Declaration

public static void SetTrackbarMax(string trackbarName, string winName, int maxVal)

Parameters

Type	Name	Description
System.String	trackbarName	Name of the trackbar.
System.String	winName	Name of the window that is the parent of trackbar.
System.Int32	maxVal	New maximum position.

SetTrackbarMin(String, String, Int32)

Sets the trackbar minimum position. The function sets the minimum position of the specified trackbar in the specified window.

Declaration

public static void SetTrackbarMin(string trackbarName, string winName, int minVal)

Parameters

Type	Name	Description
System.String	trackbarName	Name of the trackbar.
System.String	winName	Name of the window that is the parent of trackbar.
System.Int32	minVal	New minimum position.

SetTrackbarPos(String, String, Int32)

Sets the trackbar position.

Declaration

public static void SetTrackbarPos(string trackbarName, string winName, int pos)

Parameters

Type	Name	Description
System.String	trackbarName	Name of the trackbar.
System.String	winName	Name of the window that is the parent of trackbar.
System.Int32	pos	New position.

SetUseOptimized(Boolean)

Turns on/off available optimization. The function turns on or off the optimized code in OpenCV. Some optimization can not be enabled or disabled, but, for example, most of SSE code in OpenCV can be temporarily turned on or off this way.

Declaration

public static void SetUseOptimized(bool onoff)

Parameters

Type	Name	Description
System.Boolean	onoff

SetWindowProperty(String, WindowPropertyFlags, Double)

Changes parameters of a window dynamically.

Declaration

public static void SetWindowProperty(string winName, WindowPropertyFlags propId, double propValue)

Parameters

Type	Name	Description
System.String	winName	Name of the window.
WindowPropertyFlags	propId	Window property to retrieve.
System.Double	propValue	New value of the window property.

SetWindowTitle(String, String)

Updates window title

Declaration

public static void SetWindowTitle(string winName, string title)

Parameters

Type	Name	Description
System.String	winName	Name of the window
System.String	title	New title

Sobel(InputArray, OutputArray, MatType, Int32, Int32, Int32, Double, Double, BorderTypes)

Calculates the first, second, third or mixed image derivatives using an extended Sobel operator

Declaration

public static void Sobel(InputArray src, OutputArray dst, MatType ddepth, int xorder, int yorder, int ksize = 3, double scale = 1, double delta = 0, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	The source image
OutputArray	dst	The destination image; will have the same size and the same number of channels as src
OpenCvSharp.MatType	ddepth	The destination image depth
System.Int32	xorder	Order of the derivative x
System.Int32	yorder	Order of the derivative y
System.Int32	ksize	Size of the extended Sobel kernel, must be 1, 3, 5 or 7
System.Double	scale	The optional scale factor for the computed derivative values (by default, no scaling is applied
System.Double	delta	The optional delta value, added to the results prior to storing them in dst
BorderTypes	borderType	The pixel extrapolation method

Solve(InputArray, InputArray, OutputArray, DecompTypes)

solves linear system or a least-square problem

Declaration

public static bool Solve(InputArray src1, InputArray src2, OutputArray dst, DecompTypes flags = DecompTypes.LU)

Parameters

Type	Name	Description
InputArray	src1
InputArray	src2
OutputArray	dst
DecompTypes	flags

Returns

Type	Description
System.Boolean

SolveCubic(InputArray, OutputArray)

finds real roots of a cubic polynomial

Declaration

public static int SolveCubic(InputArray coeffs, OutputArray roots)

Parameters

Type	Name	Description
InputArray	coeffs	The equation coefficients, an array of 3 or 4 elements
OutputArray	roots	The destination array of real roots which will have 1 or 3 elements

Returns

Type	Description
System.Int32

SolveLP(InputArray, InputArray, OutputArray)

Solve given (non-integer) linear programming problem using the Simplex Algorithm (Simplex Method).

Declaration

public static SolveLPResult SolveLP(InputArray func, InputArray constr, OutputArray z)

Parameters

Type	Name	Description
InputArray	func	This row-vector corresponds to \f$c\f$ in the LP problem formulation (see above). It should contain 32- or 64-bit floating point numbers.As a convenience, column-vector may be also submitted, in the latter case it is understood to correspond to \f$c^T\f$.
InputArray	constr	m-by-n+1 matrix, whose rightmost column corresponds to \f$b\f$ in formulation above and the remaining to \f$A\f$. It should containt 32- or 64-bit floating point numbers.
OutputArray	z	The solution will be returned here as a column-vector - it corresponds to \f$c\f$ in the formulation above.It will contain 64-bit floating point numbers.

Returns

Type	Description
SolveLPResult

SolvePnP(IEnumerable<Point3f>, IEnumerable<Point2f>, Double[,], Nullable<IEnumerable<Double>>, ref Double[], ref Double[], Boolean, SolvePnPFlags)

Finds an object pose from 3D-2D point correspondences.

Declaration

public static void SolvePnP(IEnumerable<Point3f> objectPoints, IEnumerable<Point2f> imagePoints, double[, ] cameraMatrix, IEnumerable<double>? distCoeffs, ref double[] rvec, ref double[] tvec, bool useExtrinsicGuess = false, SolvePnPFlags flags = SolvePnPFlags.Iterative)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3f>	objectPoints	Array of object points in the object coordinate space, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel, where N is the number of points. vector<Point3f> can be also passed here.
IEnumerable<OpenCvSharp.Point2f>	imagePoints	Array of corresponding image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel, where N is the number of points. vector<Point2f> can be also passed here.
System.Double[,]	cameraMatrix	Input camera matrix
System.Nullable<IEnumerable<System.Double>>	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
System.Double[]	rvec	Output rotation vector that, together with tvec , brings points from the model coordinate system to the camera coordinate system.
System.Double[]	tvec	Output translation vector.
System.Boolean	useExtrinsicGuess	If true, the function uses the provided rvec and tvec values as initial approximations of the rotation and translation vectors, respectively, and further optimizes them.
SolvePnPFlags	flags	Method for solving a PnP problem

SolvePnP(InputArray, InputArray, InputArray, InputArray, OutputArray, OutputArray, Boolean, SolvePnPFlags)

Finds an object pose from 3D-2D point correspondences.

Declaration

public static void SolvePnP(InputArray objectPoints, InputArray imagePoints, InputArray cameraMatrix, InputArray distCoeffs, OutputArray rvec, OutputArray tvec, bool useExtrinsicGuess = false, SolvePnPFlags flags = SolvePnPFlags.Iterative)

Parameters

Type	Name	Description
InputArray	objectPoints	Array of object points in the object coordinate space, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel, where N is the number of points. vector<Point3f> can be also passed here.
InputArray	imagePoints	Array of corresponding image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel, where N is the number of points. vector<Point2f> can be also passed here.
InputArray	cameraMatrix	Input camera matrix
InputArray	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
OutputArray	rvec	Output rotation vector that, together with tvec , brings points from the model coordinate system to the camera coordinate system.
OutputArray	tvec	Output translation vector.
System.Boolean	useExtrinsicGuess	If true, the function uses the provided rvec and tvec values as initial approximations of the rotation and translation vectors, respectively, and further optimizes them.
SolvePnPFlags	flags	Method for solving a PnP problem:

SolvePnPRansac(IEnumerable<Point3f>, IEnumerable<Point2f>, Double[,], IEnumerable<Double>, out Double[], out Double[])

computes the camera pose from a few 3D points and the corresponding projections. The outliers are possible.

Declaration

public static void SolvePnPRansac(IEnumerable<Point3f> objectPoints, IEnumerable<Point2f> imagePoints, double[, ] cameraMatrix, IEnumerable<double> distCoeffs, out double[] rvec, out double[] tvec)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3f>	objectPoints	Array of object points in the object coordinate space, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel, where N is the number of points. List<Point3f> can be also passed here.
IEnumerable<OpenCvSharp.Point2f>	imagePoints	Array of corresponding image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel, where N is the number of points. List<Point2f> can be also passed here.
System.Double[,]	cameraMatrix	Input 3x3 camera matrix
IEnumerable<System.Double>	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
System.Double[]	rvec	Output rotation vector that, together with tvec , brings points from the model coordinate system to the camera coordinate system.
System.Double[]	tvec	Output translation vector.

SolvePnPRansac(IEnumerable<Point3f>, IEnumerable<Point2f>, Double[,], Nullable<IEnumerable<Double>>, out Double[], out Double[], out Int32[], Boolean, Int32, Single, Double, SolvePnPFlags)

computes the camera pose from a few 3D points and the corresponding projections. The outliers are possible.

Declaration

public static void SolvePnPRansac(IEnumerable<Point3f> objectPoints, IEnumerable<Point2f> imagePoints, double[, ] cameraMatrix, IEnumerable<double>? distCoeffs, out double[] rvec, out double[] tvec, out int[] inliers, bool useExtrinsicGuess = false, int iterationsCount = 100, float reprojectionError = 8F, double confidence = 0.99, SolvePnPFlags flags = SolvePnPFlags.Iterative)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point3f>	objectPoints	Array of object points in the object coordinate space, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel, where N is the number of points. List<Point3f> can be also passed here.
IEnumerable<OpenCvSharp.Point2f>	imagePoints	Array of corresponding image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel, where N is the number of points. List<Point2f> can be also passed here.
System.Double[,]	cameraMatrix	Input 3x3 camera matrix
System.Nullable<IEnumerable<System.Double>>	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
System.Double[]	rvec	Output rotation vector that, together with tvec , brings points from the model coordinate system to the camera coordinate system.
System.Double[]	tvec	Output translation vector.
System.Int32[]	inliers	Output vector that contains indices of inliers in objectPoints and imagePoints .
System.Boolean	useExtrinsicGuess	If true, the function uses the provided rvec and tvec values as initial approximations of the rotation and translation vectors, respectively, and further optimizes them.
System.Int32	iterationsCount	Number of iterations.
System.Single	reprojectionError	Inlier threshold value used by the RANSAC procedure. The parameter value is the maximum allowed distance between the observed and computed point projections to consider it an inlier.
System.Double	confidence	The probability that the algorithm produces a useful result.
SolvePnPFlags	flags	Method for solving a PnP problem

SolvePnPRansac(InputArray, InputArray, InputArray, InputArray, OutputArray, OutputArray, Boolean, Int32, Single, Double, OutputArray, SolvePnPFlags)

computes the camera pose from a few 3D points and the corresponding projections. The outliers are possible.

Declaration

public static void SolvePnPRansac(InputArray objectPoints, InputArray imagePoints, InputArray cameraMatrix, InputArray distCoeffs, OutputArray rvec, OutputArray tvec, bool useExtrinsicGuess = false, int iterationsCount = 100, float reprojectionError = 8F, double confidence = 0.99, OutputArray inliers = null, SolvePnPFlags flags = SolvePnPFlags.Iterative)

Parameters

Type	Name	Description
InputArray	objectPoints	Array of object points in the object coordinate space, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel, where N is the number of points. List<Point3f> can be also passed here.
InputArray	imagePoints	Array of corresponding image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel, where N is the number of points. List<Point2f> can be also passed here.
InputArray	cameraMatrix	Input 3x3 camera matrix
InputArray	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
OutputArray	rvec	Output rotation vector that, together with tvec , brings points from the model coordinate system to the camera coordinate system.
OutputArray	tvec	Output translation vector.
System.Boolean	useExtrinsicGuess	If true, the function uses the provided rvec and tvec values as initial approximations of the rotation and translation vectors, respectively, and further optimizes them.
System.Int32	iterationsCount	Number of iterations.
System.Single	reprojectionError	Inlier threshold value used by the RANSAC procedure. The parameter value is the maximum allowed distance between the observed and computed point projections to consider it an inlier.
System.Double	confidence	The probability that the algorithm produces a useful result.
OutputArray	inliers	Output vector that contains indices of inliers in objectPoints and imagePoints .
SolvePnPFlags	flags	Method for solving a PnP problem

SolvePoly(InputArray, OutputArray, Int32)

finds real and complex roots of a polynomial

Declaration

public static double SolvePoly(InputArray coeffs, OutputArray roots, int maxIters = 300)

Parameters

Type	Name	Description
InputArray	coeffs	The array of polynomial coefficients
OutputArray	roots	The destination (complex) array of roots
System.Int32	maxIters	The maximum number of iterations the algorithm does

Returns

Type	Description
System.Double

Sort(InputArray, OutputArray, SortFlags)

sorts independently each matrix row or each matrix column

Declaration

public static void Sort(InputArray src, OutputArray dst, SortFlags flags)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
OutputArray	dst	The destination array of the same size and the same type as src
SortFlags	flags	The operation flags, a combination of the SortFlag values

SortIdx(InputArray, OutputArray, SortFlags)

sorts independently each matrix row or each matrix column

Declaration

public static void SortIdx(InputArray src, OutputArray dst, SortFlags flags)

Parameters

Type	Name	Description
InputArray	src	The source single-channel array
OutputArray	dst	The destination integer array of the same size as src
SortFlags	flags	The operation flags, a combination of SortFlag values

SpatialGradient(InputArray, OutputArray, OutputArray, Int32, BorderTypes)

Calculates the first order image derivative in both x and y using a Sobel operator

Declaration

public static void SpatialGradient(InputArray src, OutputArray dx, OutputArray dy, int ksize = 3, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src	input image.
OutputArray	dx	output image with first-order derivative in x.
OutputArray	dy	output image with first-order derivative in y.
System.Int32	ksize	size of Sobel kernel. It must be 3.
BorderTypes	borderType	pixel extrapolation method

Split(Mat)

Copies each plane of a multi-channel array to a dedicated array

Declaration

public static Mat[] Split(Mat src)

Parameters

Type	Name	Description
Mat	src	The source multi-channel array

Returns

Type	Description
Mat[]	The number of arrays must match mtx.channels() . The arrays themselves will be reallocated if needed

Split(Mat, out Mat[])

Copies each plane of a multi-channel array to a dedicated array

Declaration

public static void Split(Mat src, out Mat[] mv)

Parameters

Type	Name	Description
Mat	src	The source multi-channel array
Mat[]	mv	The destination array or vector of arrays; The number of arrays must match mtx.channels() . The arrays themselves will be reallocated if needed

SqrBoxFilter(InputArray, OutputArray, Int32, Size, Nullable<Point>, Boolean, BorderTypes)

Calculates the normalized sum of squares of the pixel values overlapping the filter.

For every pixel f(x, y) in the source image, the function calculates the sum of squares of those neighboring pixel values which overlap the filter placed over the pixel f(x, y).

The unnormalized square box filter can be useful in computing local image statistics such as the the local variance and standard deviation around the neighborhood of a pixel.

Declaration

public static void SqrBoxFilter(InputArray src, OutputArray dst, int ddepth, Size ksize, Point? anchor = null, bool normalize = true, BorderTypes borderType = BorderTypes.Reflect101)

Parameters

Type	Name	Description
InputArray	src
OutputArray	dst
System.Int32	ddepth
OpenCvSharp.Size	ksize
System.Nullable<OpenCvSharp.Point>	anchor
System.Boolean	normalize
BorderTypes	borderType

Sqrt(InputArray, OutputArray)

computes square root of each matrix element (dst = src**0.5)

Declaration

public static void Sqrt(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	The source floating-point array
OutputArray	dst	The destination array; will have the same size and the same type as src

StartWindowThread()

Declaration

public static int StartWindowThread()

Returns

Type	Description
System.Int32

StereoCalibrate(IEnumerable<IEnumerable<Point3f>>, IEnumerable<IEnumerable<Point2f>>, IEnumerable<IEnumerable<Point2f>>, Double[,], Double[], Double[,], Double[], Size, OutputArray, OutputArray, OutputArray, OutputArray, CalibrationFlags, Nullable<TermCriteria>)

finds intrinsic and extrinsic parameters of a stereo camera

Declaration

public static double StereoCalibrate(IEnumerable<IEnumerable<Point3f>> objectPoints, IEnumerable<IEnumerable<Point2f>> imagePoints1, IEnumerable<IEnumerable<Point2f>> imagePoints2, double[, ] cameraMatrix1, double[] distCoeffs1, double[, ] cameraMatrix2, double[] distCoeffs2, Size imageSize, OutputArray R, OutputArray T, OutputArray E, OutputArray F, CalibrationFlags flags = CalibrationFlags.FixIntrinsic, TermCriteria? criteria = null)

Parameters

Type	Name	Description
IEnumerable<IEnumerable<OpenCvSharp.Point3f>>	objectPoints	Vector of vectors of the calibration pattern points.
IEnumerable<IEnumerable<OpenCvSharp.Point2f>>	imagePoints1	Vector of vectors of the projections of the calibration pattern points, observed by the first camera.
IEnumerable<IEnumerable<OpenCvSharp.Point2f>>	imagePoints2	Vector of vectors of the projections of the calibration pattern points, observed by the second camera.
System.Double[,]	cameraMatrix1	Input/output first camera matrix
System.Double[]	distCoeffs1	Input/output vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. The output vector length depends on the flags.
System.Double[,]	cameraMatrix2	Input/output second camera matrix. The parameter is similar to cameraMatrix1 .
System.Double[]	distCoeffs2	Input/output lens distortion coefficients for the second camera. The parameter is similar to distCoeffs1 .
OpenCvSharp.Size	imageSize	Size of the image used only to initialize intrinsic camera matrix.
OutputArray	R	Output rotation matrix between the 1st and the 2nd camera coordinate systems.
OutputArray	T	Output translation vector between the coordinate systems of the cameras.
OutputArray	E	Output essential matrix.
OutputArray	F	Output fundamental matrix.
CalibrationFlags	flags	Different flags that may be zero or a combination of the CalibrationFlag values
System.Nullable<OpenCvSharp.TermCriteria>	criteria	Termination criteria for the iterative optimization algorithm.

Returns

Type	Description
System.Double

StereoCalibrate(IEnumerable<InputArray>, IEnumerable<InputArray>, IEnumerable<InputArray>, InputOutputArray, InputOutputArray, InputOutputArray, InputOutputArray, Size, OutputArray, OutputArray, OutputArray, OutputArray, CalibrationFlags, Nullable<TermCriteria>)

finds intrinsic and extrinsic parameters of a stereo camera

Declaration

public static double StereoCalibrate(IEnumerable<InputArray> objectPoints, IEnumerable<InputArray> imagePoints1, IEnumerable<InputArray> imagePoints2, InputOutputArray cameraMatrix1, InputOutputArray distCoeffs1, InputOutputArray cameraMatrix2, InputOutputArray distCoeffs2, Size imageSize, OutputArray R, OutputArray T, OutputArray E, OutputArray F, CalibrationFlags flags = CalibrationFlags.FixIntrinsic, TermCriteria? criteria = null)

Parameters

Type	Name	Description
IEnumerable<InputArray>	objectPoints	Vector of vectors of the calibration pattern points.
IEnumerable<InputArray>	imagePoints1	Vector of vectors of the projections of the calibration pattern points, observed by the first camera.
IEnumerable<InputArray>	imagePoints2	Vector of vectors of the projections of the calibration pattern points, observed by the second camera.
InputOutputArray	cameraMatrix1	Input/output first camera matrix
InputOutputArray	distCoeffs1	Input/output vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. The output vector length depends on the flags.
InputOutputArray	cameraMatrix2	Input/output second camera matrix. The parameter is similar to cameraMatrix1 .
InputOutputArray	distCoeffs2	Input/output lens distortion coefficients for the second camera. The parameter is similar to distCoeffs1 .
OpenCvSharp.Size	imageSize	Size of the image used only to initialize intrinsic camera matrix.
OutputArray	R	Output rotation matrix between the 1st and the 2nd camera coordinate systems.
OutputArray	T	Output translation vector between the coordinate systems of the cameras.
OutputArray	E	Output essential matrix.
OutputArray	F	Output fundamental matrix.
CalibrationFlags	flags	Different flags that may be zero or a combination of the CalibrationFlag values
System.Nullable<OpenCvSharp.TermCriteria>	criteria	Termination criteria for the iterative optimization algorithm.

Returns

Type	Description
System.Double

StereoRectify(InputArray, InputArray, InputArray, InputArray, Size, InputArray, InputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, StereoRectificationFlags, Double, Size, out Rect, out Rect)

computes the rectification transformation for a stereo camera from its intrinsic and extrinsic parameters

Declaration

public static void StereoRectify(InputArray cameraMatrix1, InputArray distCoeffs1, InputArray cameraMatrix2, InputArray distCoeffs2, Size imageSize, InputArray R, InputArray T, OutputArray R1, OutputArray R2, OutputArray P1, OutputArray P2, OutputArray Q, StereoRectificationFlags flags, double alpha, Size newImageSize, out Rect validPixROI1, out Rect validPixROI2)

Parameters

Type	Name	Description
InputArray	cameraMatrix1	First camera matrix.
InputArray	distCoeffs1	First camera distortion parameters.
InputArray	cameraMatrix2	Second camera matrix.
InputArray	distCoeffs2	Second camera distortion parameters.
OpenCvSharp.Size	imageSize	Size of the image used for stereo calibration.
InputArray	R	Rotation matrix between the coordinate systems of the first and the second cameras.
InputArray	T	Translation vector between coordinate systems of the cameras.
OutputArray	R1	Output 3x3 rectification transform (rotation matrix) for the first camera.
OutputArray	R2	Output 3x3 rectification transform (rotation matrix) for the second camera.
OutputArray	P1	Output 3x4 projection matrix in the new (rectified) coordinate systems for the first camera.
OutputArray	P2	Output 3x4 projection matrix in the new (rectified) coordinate systems for the second camera.
OutputArray	Q	Output 4x4 disparity-to-depth mapping matrix (see reprojectImageTo3D() ).
StereoRectificationFlags	flags	Operation flags that may be zero or CV_CALIB_ZERO_DISPARITY. If the flag is set, the function makes the principal points of each camera have the same pixel coordinates in the rectified views. And if the flag is not set, the function may still shift the images in the horizontal or vertical direction (depending on the orientation of epipolar lines) to maximize the useful image area.
System.Double	alpha	Free scaling parameter. If it is -1 or absent, the function performs the default scaling. Otherwise, the parameter should be between 0 and 1. alpha=0 means that the rectified images are zoomed and shifted so that only valid pixels are visible (no black areas after rectification). alpha=1 means that the rectified image is decimated and shifted so that all the pixels from the original images from the cameras are retained in the rectified images (no source image pixels are lost). Obviously, any intermediate value yields an intermediate result between those two extreme cases.
OpenCvSharp.Size	newImageSize	New image resolution after rectification. The same size should be passed to initUndistortRectifyMap(). When (0,0) is passed (default), it is set to the original imageSize . Setting it to larger value can help you preserve details in the original image, especially when there is a big radial distortion.
OpenCvSharp.Rect	validPixROI1	Optional output rectangles inside the rectified images where all the pixels are valid. If alpha=0 , the ROIs cover the whole images. Otherwise, they are likely to be smaller.
OpenCvSharp.Rect	validPixROI2	Optional output rectangles inside the rectified images where all the pixels are valid. If alpha=0 , the ROIs cover the whole images. Otherwise, they are likely to be smaller.

StereoRectify(InputArray, InputArray, InputArray, InputArray, Size, InputArray, InputArray, OutputArray, OutputArray, OutputArray, OutputArray, OutputArray, StereoRectificationFlags, Double, Nullable<Size>)

computes the rectification transformation for a stereo camera from its intrinsic and extrinsic parameters

Declaration

public static void StereoRectify(InputArray cameraMatrix1, InputArray distCoeffs1, InputArray cameraMatrix2, InputArray distCoeffs2, Size imageSize, InputArray R, InputArray T, OutputArray R1, OutputArray R2, OutputArray P1, OutputArray P2, OutputArray Q, StereoRectificationFlags flags = StereoRectificationFlags.ZeroDisparity, double alpha = -1, Size? newImageSize = null)

Parameters

Type	Name	Description
InputArray	cameraMatrix1	First camera matrix.
InputArray	distCoeffs1	First camera distortion parameters.
InputArray	cameraMatrix2	Second camera matrix.
InputArray	distCoeffs2	Second camera distortion parameters.
OpenCvSharp.Size	imageSize	Size of the image used for stereo calibration.
InputArray	R	Rotation matrix between the coordinate systems of the first and the second cameras.
InputArray	T	Translation vector between coordinate systems of the cameras.
OutputArray	R1	Output 3x3 rectification transform (rotation matrix) for the first camera.
OutputArray	R2	Output 3x3 rectification transform (rotation matrix) for the second camera.
OutputArray	P1	Output 3x4 projection matrix in the new (rectified) coordinate systems for the first camera.
OutputArray	P2	Output 3x4 projection matrix in the new (rectified) coordinate systems for the second camera.
OutputArray	Q	Output 4x4 disparity-to-depth mapping matrix (see reprojectImageTo3D() ).
StereoRectificationFlags	flags	Operation flags that may be zero or CV_CALIB_ZERO_DISPARITY. If the flag is set, the function makes the principal points of each camera have the same pixel coordinates in the rectified views. And if the flag is not set, the function may still shift the images in the horizontal or vertical direction (depending on the orientation of epipolar lines) to maximize the useful image area.
System.Double	alpha	Free scaling parameter. If it is -1 or absent, the function performs the default scaling. Otherwise, the parameter should be between 0 and 1. alpha=0 means that the rectified images are zoomed and shifted so that only valid pixels are visible (no black areas after rectification). alpha=1 means that the rectified image is decimated and shifted so that all the pixels from the original images from the cameras are retained in the rectified images (no source image pixels are lost). Obviously, any intermediate value yields an intermediate result between those two extreme cases.
System.Nullable<OpenCvSharp.Size>	newImageSize	New image resolution after rectification. The same size should be passed to initUndistortRectifyMap(). When (0,0) is passed (default), it is set to the original imageSize . Setting it to larger value can help you preserve details in the original image, especially when there is a big radial distortion.

StereoRectify(Double[,], Double[], Double[,], Double[], Size, Double[,], Double[], out Double[,], out Double[,], out Double[,], out Double[,], out Double[,], StereoRectificationFlags, Double, Size, out Rect, out Rect)

computes the rectification transformation for a stereo camera from its intrinsic and extrinsic parameters

Declaration

public static void StereoRectify(double[, ] cameraMatrix1, double[] distCoeffs1, double[, ] cameraMatrix2, double[] distCoeffs2, Size imageSize, double[, ] R, double[] T, out double[, ] R1, out double[, ] R2, out double[, ] P1, out double[, ] P2, out double[, ] Q, StereoRectificationFlags flags, double alpha, Size newImageSize, out Rect validPixROI1, out Rect validPixROI2)

Parameters

Type	Name	Description
System.Double[,]	cameraMatrix1	First camera matrix.
System.Double[]	distCoeffs1	First camera distortion parameters.
System.Double[,]	cameraMatrix2	Second camera matrix.
System.Double[]	distCoeffs2	Second camera distortion parameters.
OpenCvSharp.Size	imageSize	Size of the image used for stereo calibration.
System.Double[,]	R	Rotation matrix between the coordinate systems of the first and the second cameras.
System.Double[]	T	Translation vector between coordinate systems of the cameras.
System.Double[,]	R1	Output 3x3 rectification transform (rotation matrix) for the first camera.
System.Double[,]	R2	Output 3x3 rectification transform (rotation matrix) for the second camera.
System.Double[,]	P1	Output 3x4 projection matrix in the new (rectified) coordinate systems for the first camera.
System.Double[,]	P2	Output 3x4 projection matrix in the new (rectified) coordinate systems for the second camera.
System.Double[,]	Q	Output 4x4 disparity-to-depth mapping matrix (see reprojectImageTo3D() ).
StereoRectificationFlags	flags	Operation flags that may be zero or CV_CALIB_ZERO_DISPARITY. If the flag is set, the function makes the principal points of each camera have the same pixel coordinates in the rectified views. And if the flag is not set, the function may still shift the images in the horizontal or vertical direction (depending on the orientation of epipolar lines) to maximize the useful image area.
System.Double	alpha	Free scaling parameter. If it is -1 or absent, the function performs the default scaling. Otherwise, the parameter should be between 0 and 1. alpha=0 means that the rectified images are zoomed and shifted so that only valid pixels are visible (no black areas after rectification). alpha=1 means that the rectified image is decimated and shifted so that all the pixels from the original images from the cameras are retained in the rectified images (no source image pixels are lost). Obviously, any intermediate value yields an intermediate result between those two extreme cases.
OpenCvSharp.Size	newImageSize	New image resolution after rectification. The same size should be passed to initUndistortRectifyMap(). When (0,0) is passed (default), it is set to the original imageSize . Setting it to larger value can help you preserve details in the original image, especially when there is a big radial distortion.
OpenCvSharp.Rect	validPixROI1	Optional output rectangles inside the rectified images where all the pixels are valid. If alpha=0 , the ROIs cover the whole images. Otherwise, they are likely to be smaller.
OpenCvSharp.Rect	validPixROI2	Optional output rectangles inside the rectified images where all the pixels are valid. If alpha=0 , the ROIs cover the whole images. Otherwise, they are likely to be smaller.

StereoRectify(Double[,], Double[], Double[,], Double[], Size, Double[,], Double[], out Double[,], out Double[,], out Double[,], out Double[,], out Double[,], StereoRectificationFlags, Double, Nullable<Size>)

computes the rectification transformation for a stereo camera from its intrinsic and extrinsic parameters

Declaration

public static void StereoRectify(double[, ] cameraMatrix1, double[] distCoeffs1, double[, ] cameraMatrix2, double[] distCoeffs2, Size imageSize, double[, ] R, double[] T, out double[, ] R1, out double[, ] R2, out double[, ] P1, out double[, ] P2, out double[, ] Q, StereoRectificationFlags flags = StereoRectificationFlags.ZeroDisparity, double alpha = -1, Size? newImageSize = null)

Parameters

Type	Name	Description
System.Double[,]	cameraMatrix1	First camera matrix.
System.Double[]	distCoeffs1	First camera distortion parameters.
System.Double[,]	cameraMatrix2	Second camera matrix.
System.Double[]	distCoeffs2	Second camera distortion parameters.
OpenCvSharp.Size	imageSize	Size of the image used for stereo calibration.
System.Double[,]	R	Rotation matrix between the coordinate systems of the first and the second cameras.
System.Double[]	T	Translation vector between coordinate systems of the cameras.
System.Double[,]	R1	Output 3x3 rectification transform (rotation matrix) for the first camera.
System.Double[,]	R2	Output 3x3 rectification transform (rotation matrix) for the second camera.
System.Double[,]	P1	Output 3x4 projection matrix in the new (rectified) coordinate systems for the first camera.
System.Double[,]	P2	Output 3x4 projection matrix in the new (rectified) coordinate systems for the second camera.
System.Double[,]	Q	Output 4x4 disparity-to-depth mapping matrix (see reprojectImageTo3D() ).
StereoRectificationFlags	flags	Operation flags that may be zero or CV_CALIB_ZERO_DISPARITY. If the flag is set, the function makes the principal points of each camera have the same pixel coordinates in the rectified views. And if the flag is not set, the function may still shift the images in the horizontal or vertical direction (depending on the orientation of epipolar lines) to maximize the useful image area.
System.Double	alpha	Free scaling parameter. If it is -1 or absent, the function performs the default scaling. Otherwise, the parameter should be between 0 and 1. alpha=0 means that the rectified images are zoomed and shifted so that only valid pixels are visible (no black areas after rectification). alpha=1 means that the rectified image is decimated and shifted so that all the pixels from the original images from the cameras are retained in the rectified images (no source image pixels are lost). Obviously, any intermediate value yields an intermediate result between those two extreme cases.
System.Nullable<OpenCvSharp.Size>	newImageSize	New image resolution after rectification. The same size should be passed to initUndistortRectifyMap(). When (0,0) is passed (default), it is set to the original imageSize . Setting it to larger value can help you preserve details in the original image, especially when there is a big radial distortion.

StereoRectifyUncalibrated(IEnumerable<Point2d>, IEnumerable<Point2d>, Double[,], Size, out Double[,], out Double[,], Double)

computes the rectification transformation for an uncalibrated stereo camera (zero distortion is assumed)

Declaration

public static bool StereoRectifyUncalibrated(IEnumerable<Point2d> points1, IEnumerable<Point2d> points2, double[, ] F, Size imgSize, out double[, ] H1, out double[, ] H2, double threshold = 5)

Parameters

Type	Name	Description
IEnumerable<OpenCvSharp.Point2d>	points1	Array of feature points in the first image.
IEnumerable<OpenCvSharp.Point2d>	points2	The corresponding points in the second image. The same formats as in findFundamentalMat() are supported.
System.Double[,]	F	Input fundamental matrix. It can be computed from the same set of point pairs using findFundamentalMat() .
OpenCvSharp.Size	imgSize	Size of the image.
System.Double[,]	H1	Output rectification homography matrix for the first image.
System.Double[,]	H2	Output rectification homography matrix for the second image.
System.Double	threshold	Optional threshold used to filter out the outliers. If the parameter is greater than zero, all the point pairs that do not comply with the epipolar geometry (that is, the points for which |points2[i]^T * F * points1[i]| > threshold ) are rejected prior to computing the homographies. Otherwise, all the points are considered inliers.

Returns

Type	Description
System.Boolean

StereoRectifyUncalibrated(InputArray, InputArray, InputArray, Size, OutputArray, OutputArray, Double)

computes the rectification transformation for an uncalibrated stereo camera (zero distortion is assumed)

Declaration

public static bool StereoRectifyUncalibrated(InputArray points1, InputArray points2, InputArray F, Size imgSize, OutputArray H1, OutputArray H2, double threshold = 5)

Parameters

Type	Name	Description
InputArray	points1	Array of feature points in the first image.
InputArray	points2	The corresponding points in the second image. The same formats as in findFundamentalMat() are supported.
InputArray	F	Input fundamental matrix. It can be computed from the same set of point pairs using findFundamentalMat() .
OpenCvSharp.Size	imgSize	Size of the image.
OutputArray	H1	Output rectification homography matrix for the first image.
OutputArray	H2	Output rectification homography matrix for the second image.
System.Double	threshold	Optional threshold used to filter out the outliers. If the parameter is greater than zero, all the point pairs that do not comply with the epipolar geometry (that is, the points for which |points2[i]^T * F * points1[i]| > threshold ) are rejected prior to computing the homographies. Otherwise, all the points are considered inliers.

Returns

Type	Description
System.Boolean

Stylization(InputArray, OutputArray, Single, Single)

Stylization aims to produce digital imagery with a wide variety of effects not focused on photorealism. Edge-aware filters are ideal for stylization, as they can abstract regions of low contrast while preserving, or enhancing, high-contrast features.

Declaration

public static void Stylization(InputArray src, OutputArray dst, float sigmaS = 60F, float sigmaR = 0.45F)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
OutputArray	dst	Output image with the same size and type as src.
System.Single	sigmaS	Range between 0 to 200.
System.Single	sigmaR	Range between 0 to 1.

Subtract(InputArray, InputArray, OutputArray, InputArray, Int32)

Calculates per-element difference between two arrays or array and a scalar

Declaration

public static void Subtract(InputArray src1, InputArray src2, OutputArray dst, InputArray mask = null, int dtype = -1)

Parameters

Type	Name	Description
InputArray	src1	The first source array
InputArray	src2	The second source array. It must have the same size and same type as src1
OutputArray	dst	The destination array; it will have the same size and same type as src1
InputArray	mask	The optional operation mask, 8-bit single channel array; specifies elements of the destination array to be changed. [By default this is null]
System.Int32	dtype

Subtract(InputArray, Scalar, OutputArray, InputArray, Int32)

Calculates per-element difference between two arrays or array and a scalar

Declaration

public static void Subtract(InputArray src1, Scalar src2, OutputArray dst, InputArray mask = null, int dtype = -1)

Parameters

Type	Name	Description
InputArray	src1	The first source array
OpenCvSharp.Scalar	src2	The second source array. It must have the same size and same type as src1
OutputArray	dst	The destination array; it will have the same size and same type as src1
InputArray	mask	The optional operation mask, 8-bit single channel array; specifies elements of the destination array to be changed. [By default this is null]
System.Int32	dtype

Subtract(Scalar, InputArray, OutputArray, InputArray, Int32)

Calculates per-element difference between two arrays or array and a scalar

Declaration

public static void Subtract(Scalar src1, InputArray src2, OutputArray dst, InputArray mask = null, int dtype = -1)

Parameters

Type	Name	Description
OpenCvSharp.Scalar	src1	The first source array
InputArray	src2	The second source array. It must have the same size and same type as src1
OutputArray	dst	The destination array; it will have the same size and same type as src1
InputArray	mask	The optional operation mask, 8-bit single channel array; specifies elements of the destination array to be changed. [By default this is null]
System.Int32	dtype

Sum(InputArray)

computes sum of array elements

Declaration

public static Scalar Sum(InputArray src)

Parameters

Type	Name	Description
InputArray	src	The source array; must have 1 to 4 channels

Returns

Type	Description
OpenCvSharp.Scalar

SVBackSubst(InputArray, InputArray, InputArray, InputArray, OutputArray)

performs back substitution for the previously computed SVD

Declaration

public static void SVBackSubst(InputArray w, InputArray u, InputArray vt, InputArray rhs, OutputArray dst)

Parameters

Type	Name	Description
InputArray	w	calculated singular values
InputArray	u	calculated left singular vectors
InputArray	vt	transposed matrix of right singular vectors
InputArray	rhs	right-hand side of a linear system (uwv')*dst = rhs to be solved, where A has been previously decomposed.
OutputArray	dst	output

SVDecomp(InputArray, OutputArray, OutputArray, OutputArray, SVD.Flags)

decomposes matrix and stores the results to user-provided matrices

Declaration

public static void SVDecomp(InputArray src, OutputArray w, OutputArray u, OutputArray vt, SVD.Flags flags = SVD.Flags.None)

Parameters

Type	Name	Description
InputArray	src	decomposed matrix. The depth has to be CV_32F or CV_64F.
OutputArray	w	calculated singular values
OutputArray	u	calculated left singular vectors
OutputArray	vt	transposed matrix of right singular vectors
SVD.Flags	flags	peration flags - see SVD::Flags.

TextureFlattening(InputArray, InputArray, OutputArray, Single, Single, Int32)

By retaining only the gradients at edge locations, before integrating with the Poisson solver, one washes out the texture of the selected region, giving its contents a flat aspect. Here Canny Edge Detector is used.

Declaration

public static void TextureFlattening(InputArray src, InputArray mask, OutputArray dst, float lowThreshold = 30F, float highThreshold = 45F, int kernelSize = 3)

Parameters

Type	Name	Description
InputArray	src	Input 8-bit 3-channel image.
InputArray	mask	Input 8-bit 1 or 3-channel image.
OutputArray	dst	Output image with the same size and type as src.
System.Single	lowThreshold	Range from 0 to 100.
System.Single	highThreshold	Value > 100.
System.Int32	kernelSize	The size of the Sobel kernel to be used.

Threshold(InputArray, OutputArray, Double, Double, ThresholdTypes)

Applies a fixed-level threshold to each array element.

Declaration

public static double Threshold(InputArray src, OutputArray dst, double thresh, double maxval, ThresholdTypes type)

Parameters

Type	Name	Description
InputArray	src	input array (single-channel, 8-bit or 32-bit floating point).
OutputArray	dst	output array of the same size and type as src.
System.Double	thresh	threshold value.
System.Double	maxval	maximum value to use with the THRESH_BINARY and THRESH_BINARY_INV thresholding types.
ThresholdTypes	type	thresholding type (see the details below).

Returns

Type	Description
System.Double	the computed threshold value when type == OTSU

Trace(InputArray)

computes trace of a matrix

Declaration

public static Scalar Trace(InputArray mtx)

Parameters

Type	Name	Description
InputArray	mtx	The source matrix

Returns

Type	Description
OpenCvSharp.Scalar

Transform(InputArray, OutputArray, InputArray)

performs affine transformation of each element of multi-channel input matrix

Declaration

public static void Transform(InputArray src, OutputArray dst, InputArray m)

Parameters

Type	Name	Description
InputArray	src	The source array; must have as many channels (1 to 4) as mtx.cols or mtx.cols-1
OutputArray	dst	The destination array; will have the same size and depth as src and as many channels as mtx.rows
InputArray	m	The transformation matrix

Transpose(InputArray, OutputArray)

transposes the matrix

Declaration

public static void Transpose(InputArray src, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src	The source array
OutputArray	dst	The destination array of the same type as src

TriangulatePoints(InputArray, InputArray, InputArray, InputArray, OutputArray)

Reconstructs points by triangulation.

Declaration

public static void TriangulatePoints(InputArray projMatr1, InputArray projMatr2, InputArray projPoints1, InputArray projPoints2, OutputArray points4D)

Parameters

Type	Name	Description
InputArray	projMatr1	3x4 projection matrix of the first camera.
InputArray	projMatr2	3x4 projection matrix of the second camera.
InputArray	projPoints1	2xN array of feature points in the first image. In case of c++ version it can be also a vector of feature points or two-channel matrix of size 1xN or Nx1.
InputArray	projPoints2	2xN array of corresponding points in the second image. In case of c++ version it can be also a vector of feature points or two-channel matrix of size 1xN or Nx1.
OutputArray	points4D	4xN array of reconstructed points in homogeneous coordinates.

TriangulatePoints(Double[,], Double[,], IEnumerable<Point2d>, IEnumerable<Point2d>)

Reconstructs points by triangulation.

Declaration

public static Vec4d[] TriangulatePoints(double[, ] projMatr1, double[, ] projMatr2, IEnumerable<Point2d> projPoints1, IEnumerable<Point2d> projPoints2)

Parameters

Type	Name	Description
System.Double[,]	projMatr1	3x4 projection matrix of the first camera.
System.Double[,]	projMatr2	3x4 projection matrix of the second camera.
IEnumerable<OpenCvSharp.Point2d>	projPoints1	2xN array of feature points in the first image. In case of c++ version it can be also a vector of feature points or two-channel matrix of size 1xN or Nx1.
IEnumerable<OpenCvSharp.Point2d>	projPoints2	2xN array of corresponding points in the second image. In case of c++ version it can be also a vector of feature points or two-channel matrix of size 1xN or Nx1.

Returns

Type	Description
Vec4d[]	4xN array of reconstructed points in homogeneous coordinates.

Undistort(InputArray, OutputArray, InputArray, InputArray, InputArray)

corrects lens distortion for the given camera matrix and distortion coefficients

Declaration

public static void Undistort(InputArray src, OutputArray dst, InputArray cameraMatrix, InputArray distCoeffs, InputArray newCameraMatrix = null)

Parameters

Type	Name	Description
InputArray	src	Input (distorted) image.
OutputArray	dst	Output (corrected) image that has the same size and type as src .
InputArray	cameraMatrix	Input camera matrix
InputArray	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
InputArray	newCameraMatrix	Camera matrix of the distorted image. By default, it is the same as cameraMatrix but you may additionally scale and shift the result by using a different matrix.

UndistortPoints(InputArray, OutputArray, InputArray, InputArray, InputArray, InputArray)

Computes the ideal point coordinates from the observed point coordinates.

Declaration

public static void UndistortPoints(InputArray src, OutputArray dst, InputArray cameraMatrix, InputArray distCoeffs, InputArray r = null, InputArray p = null)

Parameters

Type	Name	Description
InputArray	src	Observed point coordinates, 1xN or Nx1 2-channel (CV_32FC2 or CV_64FC2).
OutputArray	dst	Output ideal point coordinates after undistortion and reverse perspective transformation. If matrix P is identity or omitted, dst will contain normalized point coordinates.
InputArray	cameraMatrix	Camera matrix
InputArray	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
InputArray	r	Rectification transformation in the object space (3x3 matrix). R1 or R2 computed by stereoRectify() can be passed here. If the matrix is empty, the identity transformation is used.
InputArray	p	New camera matrix (3x3) or new projection matrix (3x4). P1 or P2 computed by stereoRectify() can be passed here. If the matrix is empty, the identity new camera matrix is used.

UndistortPointsIter(InputArray, OutputArray, InputArray, InputArray, InputArray, InputArray, Nullable<TermCriteria>)

Computes the ideal point coordinates from the observed point coordinates.

Declaration

public static void UndistortPointsIter(InputArray src, OutputArray dst, InputArray cameraMatrix, InputArray distCoeffs, InputArray r = null, InputArray p = null, TermCriteria? termCriteria = null)

Parameters

Type	Name	Description
InputArray	src	Observed point coordinates, 1xN or Nx1 2-channel (CV_32FC2 or CV_64FC2).
OutputArray	dst	Output ideal point coordinates after undistortion and reverse perspective transformation. If matrix P is identity or omitted, dst will contain normalized point coordinates.
InputArray	cameraMatrix	Camera matrix
InputArray	distCoeffs	Input vector of distortion coefficients (k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6]]) of 4, 5, or 8 elements. If the vector is null, the zero distortion coefficients are assumed.
InputArray	r	Rectification transformation in the object space (3x3 matrix). R1 or R2 computed by stereoRectify() can be passed here. If the matrix is empty, the identity transformation is used.
InputArray	p	New camera matrix (3x3) or new projection matrix (3x4). P1 or P2 computed by stereoRectify() can be passed here. If the matrix is empty, the identity new camera matrix is used.
System.Nullable<OpenCvSharp.TermCriteria>	termCriteria

UseOptimized()

Returns the current optimization status. The function returns the current optimization status, which is controlled by cv::setUseOptimized().

Declaration

public static bool UseOptimized()

Returns

Type	Description
System.Boolean

ValidateDisparity(InputOutputArray, InputArray, Int32, Int32, Int32)

validates disparity using the left-right check. The matrix "cost" should be computed by the stereo correspondence algorithm

Declaration

public static void ValidateDisparity(InputOutputArray disparity, InputArray cost, int minDisparity, int numberOfDisparities, int disp12MaxDisp = 1)

Parameters

Type	Name	Description
InputOutputArray	disparity
InputArray	cost
System.Int32	minDisparity
System.Int32	numberOfDisparities
System.Int32	disp12MaxDisp

VConcat(IEnumerable<Mat>, OutputArray)

Applies vertical concatenation to given matrices.

Declaration

public static void VConcat(IEnumerable<Mat> src, OutputArray dst)

Parameters

Type	Name	Description
IEnumerable<Mat>	src	input array or vector of matrices. all of the matrices must have the same number of cols and the same depth.
OutputArray	dst	output array. It has the same number of cols and depth as the src, and the sum of rows of the src.

VConcat(InputArray, InputArray, OutputArray)

Applies vertical concatenation to given matrices.

Declaration

public static void VConcat(InputArray src1, InputArray src2, OutputArray dst)

Parameters

Type	Name	Description
InputArray	src1	first input array to be considered for vertical concatenation.
InputArray	src2	second input array to be considered for vertical concatenation.
OutputArray	dst	output array. It has the same number of cols and depth as the src1 and src2, and the sum of rows of the src1 and src2.

WaitKey(Int32)

Waits for a pressed key.

Declaration

public static int WaitKey(int delay = 0)

Parameters

Type	Name	Description
System.Int32	delay	Delay in milliseconds. 0 is the special value that means ”forever”

Returns

Type	Description
System.Int32	Returns the code of the pressed key or -1 if no key was pressed before the specified time had elapsed.

WaitKeyEx(Int32)

Waits for a pressed key. Similar to #waitKey, but returns full key code. Key code is implementation specific and depends on used backend: QT/GTK/Win32/etc

Declaration

public static int WaitKeyEx(int delay = 0)

Parameters

Type	Name	Description
System.Int32	delay	Delay in milliseconds. 0 is the special value that means ”forever”

Returns

Type	Description
System.Int32	Returns the code of the pressed key or -1 if no key was pressed before the specified time had elapsed.

WarpAffine(InputArray, OutputArray, InputArray, Size, InterpolationFlags, BorderTypes, Nullable<Scalar>)

Applies an affine transformation to an image.

Declaration

public static void WarpAffine(InputArray src, OutputArray dst, InputArray m, Size dsize, InterpolationFlags flags = InterpolationFlags.Linear, BorderTypes borderMode = BorderTypes.Constant, Scalar? borderValue = null)

Parameters

Type	Name	Description
InputArray	src	input image.
OutputArray	dst	output image that has the size dsize and the same type as src.
InputArray	m	2x3 transformation matrix.
OpenCvSharp.Size	dsize	size of the output image.
InterpolationFlags	flags	combination of interpolation methods and the optional flag WARP_INVERSE_MAP that means that M is the inverse transformation (dst -> src) .
BorderTypes	borderMode	pixel extrapolation method; when borderMode=BORDER_TRANSPARENT, it means that the pixels in the destination image corresponding to the "outliers" in the source image are not modified by the function.
System.Nullable<OpenCvSharp.Scalar>	borderValue	value used in case of a constant border; by default, it is 0.

WarpPerspective(InputArray, OutputArray, InputArray, Size, InterpolationFlags, BorderTypes, Nullable<Scalar>)

Applies a perspective transformation to an image.

Declaration

public static void WarpPerspective(InputArray src, OutputArray dst, InputArray m, Size dsize, InterpolationFlags flags = InterpolationFlags.Linear, BorderTypes borderMode = BorderTypes.Constant, Scalar? borderValue = null)

Parameters

Type	Name	Description
InputArray	src	input image.
OutputArray	dst	output image that has the size dsize and the same type as src.
InputArray	m	3x3 transformation matrix.
OpenCvSharp.Size	dsize	size of the output image.
InterpolationFlags	flags	combination of interpolation methods (INTER_LINEAR or INTER_NEAREST) and the optional flag WARP_INVERSE_MAP, that sets M as the inverse transformation (dst -> src).
BorderTypes	borderMode	pixel extrapolation method (BORDER_CONSTANT or BORDER_REPLICATE).
System.Nullable<OpenCvSharp.Scalar>	borderValue	value used in case of a constant border; by default, it equals 0.

WarpPerspective(InputArray, OutputArray, Single[,], Size, InterpolationFlags, BorderTypes, Nullable<Scalar>)

Applies a perspective transformation to an image.

Declaration

public static void WarpPerspective(InputArray src, OutputArray dst, float[, ] m, Size dsize, InterpolationFlags flags = InterpolationFlags.Linear, BorderTypes borderMode = BorderTypes.Constant, Scalar? borderValue = null)

Parameters

Type	Name	Description
InputArray	src	input image.
OutputArray	dst	output image that has the size dsize and the same type as src.
System.Single[,]	m	3x3 transformation matrix.
OpenCvSharp.Size	dsize	size of the output image.
InterpolationFlags	flags	combination of interpolation methods (INTER_LINEAR or INTER_NEAREST) and the optional flag WARP_INVERSE_MAP, that sets M as the inverse transformation (dst -> src).
BorderTypes	borderMode	pixel extrapolation method (BORDER_CONSTANT or BORDER_REPLICATE).
System.Nullable<OpenCvSharp.Scalar>	borderValue	value used in case of a constant border; by default, it equals 0.

WarpPolar(InputArray, OutputArray, Size, Point2f, Double, InterpolationFlags, WarpPolarMode)

Remaps an image to polar or semilog-polar coordinates space.

Declaration

public static void WarpPolar(InputArray src, OutputArray dst, Size dsize, Point2f center, double maxRadius, InterpolationFlags interpolationFlags, WarpPolarMode warpPolarMode)

Parameters

Type	Name	Description
InputArray	src	Source image.
OutputArray	dst	Destination image. It will have same type as src.
OpenCvSharp.Size	dsize	The destination image size (see description for valid options).
OpenCvSharp.Point2f	center	The transformation center.
System.Double	maxRadius	The radius of the bounding circle to transform. It determines the inverse magnitude scale parameter too.
InterpolationFlags	interpolationFlags	interpolation methods.
WarpPolarMode	warpPolarMode	interpolation methods.

Remarks

• The function can not operate in-place.
• To calculate magnitude and angle in degrees #cartToPolar is used internally thus angles are measured from 0 to 360 with accuracy about 0.3 degrees.
• This function uses #remap. Due to current implementation limitations the size of an input and output images should be less than 32767x32767.

Watershed(InputArray, InputOutputArray)

Performs a marker-based image segmentation using the watershed algorithm.

Declaration

public static void Watershed(InputArray image, InputOutputArray markers)

Parameters

Type	Name	Description
InputArray	image	Input 8-bit 3-channel image.
InputOutputArray	markers	Input/output 32-bit single-channel image (map) of markers. It should have the same size as image.