ClassesClassesClassesClasses | | | | Operators

zero_crossingzero_crossingZeroCrossingzero_crossingZeroCrossingZeroCrossing (Operator)

Name

zero_crossingzero_crossingZeroCrossingzero_crossingZeroCrossingZeroCrossing — Extract zero crossings from an image.

Signature

zero_crossing(Image : RegionCrossing : : )

Herror zero_crossing(const Hobject Image, Hobject* RegionCrossing)

Herror T_zero_crossing(const Hobject Image, Hobject* RegionCrossing)

Herror zero_crossing(Hobject Image, Hobject* RegionCrossing)

HRegion HImage::ZeroCrossing() const

HRegionArray HImageArray::ZeroCrossing() const

void ZeroCrossing(const HObject& Image, HObject* RegionCrossing)

HRegion HImage::ZeroCrossing() const

void HOperatorSetX.ZeroCrossing(
[in] IHUntypedObjectX* Image, [out] IHUntypedObjectX*RegionCrossing)

IHRegionX* HImageX.ZeroCrossing()

static void HOperatorSet.ZeroCrossing(HObject image, out HObject regionCrossing)

HRegion HImage.ZeroCrossing()

Description

zero_crossingzero_crossingZeroCrossingzero_crossingZeroCrossingZeroCrossing returns the zero crossings of the input image as a region. A pixel is accepted as a zero crossing if its gray value (in ImageImageImageImageImageimage) is zero, or if at least one of its neighbors of the 4-neighborhood has a different sign.

This operator is intended to be used after edge operators returning the second derivative of the image (e.g., laplace_of_gausslaplace_of_gaussLaplaceOfGausslaplace_of_gaussLaplaceOfGaussLaplaceOfGauss), which were possibly followed by a smoothing operator. In this case, the zero crossings are (candidates for) edges.

Parallelization

Parameters

ImageImageImageImageImageimage (input_object)  singlechannelimage(-array) objectHImageHImageHImageHImageXHobject (int1 / int2 / int4 / real)

Input image.

RegionCrossingRegionCrossingRegionCrossingRegionCrossingRegionCrossingregionCrossing (output_object)  region(-array) objectHRegionHRegionHRegionHRegionXHobject *

Zero crossings.

Result

zero_crossingzero_crossingZeroCrossingzero_crossingZeroCrossingZeroCrossing usually returns the value 2 (H_MSG_TRUE). If necessary, an exception is raised.

Possible Predecessors

laplacelaplaceLaplacelaplaceLaplaceLaplace, laplace_of_gausslaplace_of_gaussLaplaceOfGausslaplace_of_gaussLaplaceOfGaussLaplaceOfGauss, derivate_gaussderivate_gaussDerivateGaussderivate_gaussDerivateGaussDerivateGauss

Possible Successors

connectionconnectionConnectionconnectionConnectionConnection, skeletonskeletonSkeletonskeletonSkeletonSkeleton, boundaryboundaryBoundaryboundaryBoundaryBoundary, select_shapeselect_shapeSelectShapeselect_shapeSelectShapeSelectShape, fill_upfill_upFillUpfill_upFillUpFillUp

Alternatives

thresholdthresholdThresholdthresholdThresholdThreshold, dual_thresholddual_thresholdDualThresholddual_thresholdDualThresholdDualThreshold, zero_crossing_sub_pixzero_crossing_sub_pixZeroCrossingSubPixzero_crossing_sub_pixZeroCrossingSubPixZeroCrossingSubPix

Module

Foundation


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