Intel® Integrated Performance Primitives (Intel® IPP) Developer Guide and Reference

ID 790148
Date 3/22/2024
Public
Document Table of Contents

DecimateFilterRow, DecimateFilterColumn

Decimates an image by rows or by columns.

Syntax

IppStatus ippiDecimateFilterRow_8u_C1R(const Ipp8u* pSrc, int srcStep, IppiSize srcRoiSize, Ipp8u* pDst, int dstStep, IppiFraction fraction);

IppStatus ippiDecimateFilterColumn_8u_C1R(const Ipp8u* pSrc, int srcStep, IppiSize srcRoiSize, Ipp8u* pDst, int dstStep, IppiFraction fraction);

Include Files

ippi.h

Domain Dependencies

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

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

Parameters

pSrc

Pointer to the source image ROI.

srcStep

Distance in bytes between starts of consecutive lines in the source image.

srcRoiSize

Size of the source image ROI in pixels.

pDst

Pointer to the destination image.

dstStep

Distance in bytes between starts of consecutive lines in the destination image.

fraction

Specifies how the decimating is performed. Possible values:

ippPolyphase_1_2,

ippPolyphase_3_5,

ippPolyphase_2_3,

ippPolyphase_7_10,

ippPolyphase_3_4.

Description

These functions operate with ROI (see Regions of Interest in Intel IPP).

Functions DecimateFilterRow and DecimateFilterColumn perform decimating of the source image by rows or by columns respectively. These functions use the set of special internal polyphase filters. The parameter fraction specifies how the decimating is performed, for example, if the parameter is set to ippPolyphase_3_5, then each 5 pixels in the row (or column) of the source image give 3 pixels to the destination image, if the parameter is set to ippPolyphase_1_2, then each two pixels in the row (or column) of the source image give 1 pixel to the destination image, an so on.

To ensure valid operation, the application must correctly define additional border pixels (see Borders in Neighborhood Operations). For all fraction values the width of the border is four columns/rows all around the source image ROI.

Return Values

ippStsNoErr

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

ippStsNullPtrErr

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

ippStsSizeErr

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

ippStsStepErr

Indicates an error if srcStep or dstStep is less than or equal to zero.

ippStsDecimateFractionErr

Indicates an error if fraction has an illegal value.