Developer Reference for Intel® Integrated Performance Primitives 2019

CannyBorder

Implements Canny algorithm for edge detection.

Syntax

IppStatus ippiCannyBorder_8u_C1R(const Ipp8u* pSrc, int srcStep, Ipp8u* pDst, int dstStep, IppiSize roiSize, IppiDifferentialKernel filterType, IppiMaskSize mask, IppiBorderType borderType, Ipp8u borderValue, Ipp32f lowThresh, Ipp32f highThresh, IppNormType norm, Ipp8u* pBuffer);

Include Files

ippcv.h

Domain Dependencies

Headers: ippcore.h, ippvm.h, ipps.h, ippi.h

Libraries: ippcore.lib, ippvm.lib, ipps.lib, ippi.lib

Parameters

pSrc
Pointer to the source image.
srcStep
Distance, in bytes, between the starting points of consecutive lines in the source image.
pDst
Pointer to the destination image.
dstStep
Distance, in bytes, between the starting points of consecutive lines in the destination image.
roiSize
Size of the source image ROI in pixels.
filterType
Type of the filter to be applied. Possible values are ippFilterSobel and ippFilterScharr.
mask
The size of the mask. Possible values are ippMskSize3x3 and ippMskSize5x5 for ippFilterSobel, and ippMskSize3x3 for ippFilterScharr.
borderType

Type of border. Possible values are:

ippBorderConst

Values of all border pixels are set to constant.

ippBorderRepl

Border is replicated from the edge pixels.

ippBorderInMem

Border is obtained from the source image pixels in memory.

Mixed borders are also supported. They can be obtained by the bitwise operation OR between ippBorderRepl and ippBorderInMemTop, ippBorderInMemBottom, ippBorderInMemLeft, ippBorderInMemRight.

borderValue

Constant value to assign to pixels of the constant border. This parameter is applicable only to the ippBorderConst border type.

lowThresh
Lower threshold for edges detection.
highThresh
Upper threshold for edges detection.
norm
Normalization mode. Possible values are ippNormL1 and ippNormL2.
pBuffer
Pointer to the pre-allocated temporary buffer. To calculate the size of the temporary buffer, use the CannyBorderGetSize function.

Description

This function operates with ROI (see Regions of Interest in Intel IPP). This function finds edges in the ROI of the source image with the user-defined border types using the Canny edge detector algorithm. The output image is stored in pDst.

Before using this function, compute the size of the temporary work buffer using the CannyBorderGetSize function.

Return Values

ippStsNoErr

Indicates no error. Any other value indicates an error or a warning.

ippStsNullPtrErr

Indicates an error when one of the specified pointers is NULL.

ippStsMaskSizeErr

Indicates an error when mask has an illegal value.

ippStsSizeErr

Indicates an error when roiSize has a field with a zero or negative value.

ippStsStepErr

Indicates an error when srcStep or dstStep is less than roi.width*<pixelSize>.

ippStsBadArgErr

Indicates an error when lowThresh is negative, or highThresh is less than lowThresh.

ippStsNotEvenStepErr

Indicates an error when one of the step values is not divisible by 2 for 16s images, and by 4 for 32f images.

Example

CannyBorder.c

See Also