Class PCTSignaturesSQFD

Namespace

OpenCvSharp.XFeatures2D

Assembly

OpenCvSharp.dll

Class implementing Signature Quadratic Form Distance (SQFD).

public class PCTSignaturesSQFD : Algorithm, IDisposable

Inheritance

object

CvObject

CvPtrObject

Algorithm

PCTSignaturesSQFD

Implements

IDisposable

Inherited Members

Algorithm.Write(FileStorage)

Algorithm.Read(FileNode)

Algorithm.Empty

Algorithm.Save(string)

Algorithm.GetDefaultName()

CvPtrObject.RawPtr

CvObject.IsDisposed

CvObject.ptr

CvObject.SetSafeHandle(OpenCvSafeHandle)

CvObject.Dispose()

CvObject.Dispose(bool)

CvObject.DisposeManaged()

CvObject.DisposeUnmanaged()

CvObject.ThrowIfDisposed()

CvObject.CvPtr

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Methods

ComputeQuadraticFormDistance(InputArray, InputArray)

Computes the Signature Quadratic Form Distance of two signatures.

public float ComputeQuadraticFormDistance(InputArray signature0, InputArray signature1)

Parameters

signature0 InputArray

The first signature.

signature1 InputArray

The second signature.

Returns

float

ComputeQuadraticFormDistances(Mat, IEnumerable<Mat>)

Computes the Signature Quadratic Form Distance between the reference signature and each of the other image signatures.

public float[] ComputeQuadraticFormDistances(Mat sourceSignature, IEnumerable<Mat> imageSignatures)

Parameters

sourceSignature Mat

The signature to measure the distance of other signatures from.

imageSignatures IEnumerable<Mat>

Vector of signatures to measure the distance from the source signature.

Returns

float[]

Measured distances.

Remarks

OpenCV's native implementation has a known bug for imageSignatures with more than one element: it validates each signature via mImageSignatures[i].empty() where mImageSignatures is a pointer to the whole vector rather than an element accessor, so any index beyond 0 reads out-of-bounds memory. Prefer calling ComputeQuadraticFormDistance(InputArray, InputArray) in a loop for more than one signature.

Create(PCTSignaturesDistanceFunction, PCTSignaturesSimilarityFunction, float)

Creates the algorithm instance using the selected distance function, similarity function, and similarity function parameter.

public static PCTSignaturesSQFD Create(PCTSignaturesDistanceFunction distanceFunction = PCTSignaturesDistanceFunction.L2, PCTSignaturesSimilarityFunction similarityFunction = PCTSignaturesSimilarityFunction.Heuristic, float similarityParameter = 1)

Parameters

distanceFunction PCTSignaturesDistanceFunction

Distance function selector.

similarityFunction PCTSignaturesSimilarityFunction

Similarity function selector.

similarityParameter float

Parameter of the similarity function.

Returns

PCTSignaturesSQFD