Applies the Gaussian to image and then performs down-sampling.
Syntax
IppStatus ippiPyrDown_Gauss5x5_<mod>(const Ipp<datatype>* pSrc, int srcStep, Ipp<datatype>* pDst, int dstStep, IppiSize roiSize, Ipp8u* pBuffer);
Supported values for mod:
8u_C1R |
8s_C1R |
32f_C1R |
8u_C3R |
8s_C3R |
32f_C3R |
Parameters
- pSrc
- Pointer to the source image ROI.
- srcStep
- Distance in bytes between starts of consecutive lines in the source image.
- pDst
- Pointer to the destination image ROI.
- dstStep
- Distance in bytes between starts of consecutive lines in the destination image.
- roiSize
- Size of the source image ROI in pixels.
- pBuffer
- Pointer to the temporary buffer.
Description
The function ippiPyrDown is declared in the ippcv.h file. It operates with ROI (see Regions of Interest in Intel IPP).
This function applies the 5x5 Gaussian
to the source image pSrc and
then down-samples it, that is, removes odd rows and columns from
the image. The size of the destination image is (
roiSize.height+1)/2 * (
roiSize.width+1)/2. The following
Gaussian mask is used:
The function uses the temporary buffer pBuffer - its size should be computed using the function ippiPyrDownGetBufSize beforehand.
Return Values
ippStsNoErr |
Indicates no error. Any other value indicates an error or a warning. |
ippStsNullPtr |
Indicates an error condition if one of the specified pointers is NULL. |
ippStsSizeErr |
Indicates an error condition if roiSize has a field with zero or negative value. |
ippStsStepErr |
Indicates an error condition if srcStep is less than roiSize.width * <pixelSize> , or dstStep is less than (roiSize.width * <pixelSize>)/2. |
ippStsNotEvenStepErr |
Indicates an error condition if steps for floating-point images are not divisible by 4. |