DownsampleFour16x16

Performs factor-of-4 downsampling on a 16x16 block.

Syntax

IppStatus ippiDownsampleFour16x16_H263_16s_C1R(const Ipp16s* pSrc, int srcStep, Ipp16s* pDst, int dstStep);

Parameters

pSrc	Pointer to the origin of the source 16x16 block.
srcStep	Width in bytes of the source image plane, that is, distance in bytes between the starts of consecutive lines of the source block.
pDst	Pointer to the origin of the destination 8x8 block.
dstStep	Width in bytes of the destination image plane.

Description

The function ippiDownsampleFour16x16_H263_16s_C1R is declared in the ippvc.h header file. This function performs factor-of-4 downsampling of a 16x16 source block to an 8x8 destination block, which is used for block encoding in Reduced-Resolution Update mode specified in [ITUH263], Annex Q. The inverse factor-of-4 upsampling procedure, specified in [ITUH263], Annex Q, clause Q.6, is performed by the function UpsampleFour8x8_H263.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error condition if at least one of the specified pointers is NULL.