Struct DetectorParameters
- Namespace
- OpenCvSharp.Aruco
- Assembly
- OpenCvSharp.dll
Parameters for the detectMarker process
public struct DetectorParameters
- Inherited Members
Constructors
- DetectorParameters()
Constructor
Fields
- AdaptiveThreshConstant
constant for adaptive thresholding before finding contours (default 7)
- AdaptiveThreshWinSizeMax
adaptiveThreshWinSizeMax: maximum window size for adaptive thresholding before finding contours(default 23).
- AdaptiveThreshWinSizeMin
minimum window size for adaptive thresholding before finding contours (default 3).
- AdaptiveThreshWinSizeStep
increments from adaptiveThreshWinSizeMin to adaptiveThreshWinSizeMax during the thresholding(default 10).
- AprilTagCriticalRad
Reject quads where pairs of edges have angles that are close to straight or close to 180 degrees. Zero means that no quads are rejected. (In radians).
- AprilTagDeglitch
should the thresholded image be deglitched? Only useful for very noisy images
- AprilTagMaxLineFitMse
When fitting lines to the contours, what is the maximum mean squared error allowed? This is useful in rejecting contours that are far from being quad shaped; rejecting these quads "early" saves expensive decoding processing.
- AprilTagMaxNmaxima
how many corner candidates to consider when segmenting a group of pixels into a quad.
- AprilTagMinClusterPixels
reject quads containing too few pixels.
- AprilTagMinWhiteBlackDiff
When we build our model of black & white pixels, we add an extra check that the white model must be (overall) brighter than the black model. How much brighter? (in pixel values, [0,255]).
- AprilTagQuadDecimate
Detection of quads can be done on a lower-resolution image, improving speed at a cost of pose accuracy and a slight decrease in detection rate. Decoding the binary payload is still done at full resolution.
- AprilTagQuadSigma
What Gaussian blur should be applied to the segmented image (used for quad detection?) Parameter is the standard deviation in pixels. Very noisy images benefit from non-zero values (e.g. 0.8).
- CornerRefinementMaxIterations
maximum number of iterations for stop criteria of the corner refinement process(default 30).
- CornerRefinementMethod
corner refinement method. (CORNER_REFINE_NONE, no refinement. CORNER_REFINE_SUBPIX, do subpixel refinement. CORNER_REFINE_CONTOUR use contour-Points)
- CornerRefinementMinAccuracy
minimum error for the stop criteria of the corner refinement process(default: 0.1)
- CornerRefinementWinSize
window size for the corner refinement process (in pixels) (default 5).
- ErrorCorrectionRate
errorCorrectionRate error correction rate respect to the maximun error correction capability for each dictionary. (default 0.6).
- MarkerBorderBits
number of bits of the marker border, i.e. marker border width (default 1).
- MaxErroneousBitsInBorderRate
maximum number of accepted erroneous bits in the border (i.e. number of allowed white bits in the border). Represented as a rate respect to the total number of bits per marker(default 0.35).
- MaxMarkerPerimeterRate
determine maximum perimeter for marker contour to be detected. This is defined as a rate respect to the maximum dimension of the input image(default 4.0).
- MinCornerDistanceRate
minimum distance between corners for detected markers relative to its perimeter(default 0.05)
- MinDistanceToBorder
minimum distance of any corner to the image border for detected markers (in pixels) (default 3)
- MinGroupDistance
minimum average distance between the corners of the two markers in group to add them to the list of candidates (default 0.21).
- MinMarkerDistanceRate
minimum mean distance between two marker corners to be considered similar, so that the smaller one is removed.The rate is relative to the smaller perimeter of the two markers(default 0.05).
- MinMarkerLengthRatioOriginalImg
range [0,1], eq (2) from paper. The parameter tau_i has a direct influence on the processing speed.
- MinMarkerPerimeterRate
determine minimum perimeter for marker contour to be detected. This is defined as a rate respect to the maximum dimension of the input image(default 0.03).
- MinOtsuStdDev
minimun standard deviation in pixels values during the decodification step to apply Otsu thresholding(otherwise, all the bits are set to 0 or 1 depending on mean higher than 128 or not) (default 5.0)
- MinSideLengthCanonicalImg
minimum side length of a marker in the canonical image. Latter is the binarized image in which contours are searched.
- PerspectiveRemoveIgnoredMarginPerCell
width of the margin of pixels on each cell not considered for the determination of the cell bit.Represents the rate respect to the total size of the cell, i.e. perspectiveRemovePixelPerCell (default 0.13)
- PerspectiveRemovePixelPerCell
number of bits (per dimension) for each cell of the marker when removing the perspective(default 8).
- PolygonalApproxAccuracyRate
minimum accuracy during the polygonal approximation process to determine which contours are squares.
- RelativeCornerRefinmentWinSize
Dynamic window size for corner refinement relative to Aruco module size (default 0.3).
Properties
- DetectInvertedMarker
to check if there is a white marker. In order to generate a "white" marker just invert a normal marker by using a tilde, ~markerImage. (default false)
- UseAruco3Detection
enable the new and faster Aruco detection strategy. Proposed in the paper:
- Romero-Ramirez et al: Speeded up detection of squared fiducial markers (2018)
- https://www.researchgate.net/publication/325787310_Speeded_Up_Detection_of_Squared_Fiducial_Markers