DCT8x8Inv_AANTransposed_16s8u

Performs inverse DCT on pre-transposed block and converts output to unsigned char format.

Syntax

ippiDCT8x8Inv_AANTransposed_16s8u_C1R(const Ipp16s* pSrc, Ipp8u* pDst, Ipp32s dstStep, Ipp32s count);

Parameters

pSrc	Pointer to the block of DCT coefficients.
pDst	Pointer to the destination array.
dstStep	Distance in bytes between starts of the consecutive lines in the destination image.
count	Number of the last non-zero coefficient in zig-zag order. If the block contains no non-zero coefficients, pass the value -1.

Description

This function is declared in the ippvc.h header file. The function ippiDCT8x8Inv_AANTransposed_16s8u_C1R is used for intra macroblocks. The function performs inverse DCT on a transposed block and converts the output to unsigned char format. The block is transposed during the rearranging stage of VCL decoding, using the transposed scanning matrix as scanMatrix argument of the functions ReconstructDCTBlockIntra_MPEG1 and ReconstructDCTBlockIntra_MPEG2.

This function is used in the MPEG-2 decoder included into Intel IPP Samples. See introduction to MPEG-1 and MPEG-2.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error when at least one input pointer is NULL.