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kirsch_dirkirsch_dirKirschDirkirsch_dirKirschDirKirschDir (Operator)

Name

kirsch_dirkirsch_dirKirschDirkirsch_dirKirschDirKirschDir — Detect edges (amplitude and direction) using the Kirsch operator.

Signature

kirsch_dir(Image : ImageEdgeAmp, ImageEdgeDir : : )

Herror kirsch_dir(const Hobject Image, Hobject* ImageEdgeAmp, Hobject* ImageEdgeDir)

Herror T_kirsch_dir(const Hobject Image, Hobject* ImageEdgeAmp, Hobject* ImageEdgeDir)

Herror kirsch_dir(Hobject Image, Hobject* ImageEdgeAmp, Hobject* ImageEdgeDir)

HImage HImage::KirschDir(HImage* ImageEdgeDir) const

HImageArray HImageArray::KirschDir(HImageArray* ImageEdgeDir) const

void KirschDir(const HObject& Image, HObject* ImageEdgeAmp, HObject* ImageEdgeDir)

HImage HImage::KirschDir(HImage* ImageEdgeDir) const

void HOperatorSetX.KirschDir(
[in] IHUntypedObjectX* Image, [out] IHUntypedObjectX*ImageEdgeAmp, [out] IHUntypedObjectX*ImageEdgeDir)

IHImageX* HImageX.KirschDir([out] IHImageX*ImageEdgeDir)

static void HOperatorSet.KirschDir(HObject image, out HObject imageEdgeAmp, out HObject imageEdgeDir)

HImage HImage.KirschDir(out HImage imageEdgeDir)

Description

kirsch_dirkirsch_dirKirschDirkirsch_dirKirschDirKirschDir calculates an approximation of the first derivative of the image data and is used as an edge detector. The filter is based on the following filter masks:

      -3  -3   5       -3   5   5      5   5   5       5   5  -3
      -3   0   5       -3   0   5     -3   0  -3       5   0  -3
      -3  -3   5       -3  -3  -3     -3  -3  -3      -3  -3  -3

       5  -3  -3       -3  -3  -3     -3  -3  -3      -3  -3  -3
       5   0  -3        5   0  -3     -3   0  -3      -3   0   5
       5  -3  -3        5   5  -3      5   5   5      -3   5   5
The result image contains the maximum response of all masks. The edge directions are returned in ImageEdgeDirImageEdgeDirImageEdgeDirImageEdgeDirImageEdgeDirimageEdgeDir, and are stored as x / 2. They correspond to the direction of the mask yielding the maximum response.

Attention

Note that filter operators may return unexpected results if an image with a reduced domain is used as input. Please refer to the chapter Filters.

Parallelization

Parameters

ImageImageImageImageImageimage (input_object)  (multichannel-)image(-array) objectHImageHImageHImageHImageXHobject (byte / int2 / uint2)

Input image.

ImageEdgeAmpImageEdgeAmpImageEdgeAmpImageEdgeAmpImageEdgeAmpimageEdgeAmp (output_object)  (multichannel-)image(-array) objectHImageHImageHImageHImageXHobject * (byte / int2 / uint2)

Edge amplitude (gradient magnitude) image.

ImageEdgeDirImageEdgeDirImageEdgeDirImageEdgeDirImageEdgeDirimageEdgeDir (output_object)  (multichannel-)image(-array) objectHImageHImageHImageHImageXHobject * (direction)

Edge direction image.

Example (HDevelop)

read_image(Image,'fabrik')
kirsch_dir(Image,Kirsch_dirA,Kirsch_dirD)
threshold(Kirsch_dirA,Res,128,255)

Example (C)

read_image(&Image,"fabrik");
kirsch_dir(Image,&Kirsch_dirA,&Kirsch_dirD);
threshold(Kirsch_dirA,&Res,128,255);

Example (HDevelop)

read_image(Image,'fabrik')
kirsch_dir(Image,Kirsch_dirA,Kirsch_dirD)
threshold(Kirsch_dirA,Res,128,255)

Example (HDevelop)

read_image(Image,'fabrik')
kirsch_dir(Image,Kirsch_dirA,Kirsch_dirD)
threshold(Kirsch_dirA,Res,128,255)

Example (HDevelop)

read_image(Image,'fabrik')
kirsch_dir(Image,Kirsch_dirA,Kirsch_dirD)
threshold(Kirsch_dirA,Res,128,255)

Example (HDevelop)

read_image(Image,'fabrik')
kirsch_dir(Image,Kirsch_dirA,Kirsch_dirD)
threshold(Kirsch_dirA,Res,128,255)

Result

kirsch_dirkirsch_dirKirschDirkirsch_dirKirschDirKirschDir always returns 2 (H_MSG_TRUE). If the input is empty the behavior can be set via set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>). If necessary, an exception is raised.

Possible Predecessors

binomial_filterbinomial_filterBinomialFilterbinomial_filterBinomialFilterBinomialFilter, gauss_filtergauss_filterGaussFiltergauss_filterGaussFilterGaussFilter, sigma_imagesigma_imageSigmaImagesigma_imageSigmaImageSigmaImage, median_imagemedian_imageMedianImagemedian_imageMedianImageMedianImage, smooth_imagesmooth_imageSmoothImagesmooth_imageSmoothImageSmoothImage

Possible Successors

hysteresis_thresholdhysteresis_thresholdHysteresisThresholdhysteresis_thresholdHysteresisThresholdHysteresisThreshold, thresholdthresholdThresholdthresholdThresholdThreshold, gray_skeletongray_skeletonGraySkeletongray_skeletonGraySkeletonGraySkeleton, nonmax_suppression_dirnonmax_suppression_dirNonmaxSuppressionDirnonmax_suppression_dirNonmaxSuppressionDirNonmaxSuppressionDir, close_edgesclose_edgesCloseEdgesclose_edgesCloseEdgesCloseEdges, close_edges_lengthclose_edges_lengthCloseEdgesLengthclose_edges_lengthCloseEdgesLengthCloseEdgesLength

Alternatives

edges_imageedges_imageEdgesImageedges_imageEdgesImageEdgesImage, sobel_dirsobel_dirSobelDirsobel_dirSobelDirSobelDir, robinson_dirrobinson_dirRobinsonDirrobinson_dirRobinsonDirRobinsonDir, prewitt_dirprewitt_dirPrewittDirprewitt_dirPrewittDirPrewittDir, frei_dirfrei_dirFreiDirfrei_dirFreiDirFreiDir

See also

bandpass_imagebandpass_imageBandpassImagebandpass_imageBandpassImageBandpassImage, laplace_of_gausslaplace_of_gaussLaplaceOfGausslaplace_of_gaussLaplaceOfGaussLaplaceOfGauss

Module

Foundation


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