DisassembleChroma420Intra

Disassembles intra chroma macroblocks.

Syntax

IppStatus ippiDisassembleChroma420Intra_AVS_16s8u_C1R(const Ipp8u* pSrcPlane[2], Ipp32s srcStep, Ipp8u* pDstPlane[2], Ipp32s dstStep, Ipp16s** ppDstCoeff, const IppIntraChromaPredMode_AVS* pPredModes, Ipp32u* pChromaCBP, Ipp32u QP, Ipp32u edgeType);

Parameters

pSrcPlane	Array of pointers to the source macroblock that is coded in U-plane and Y-plane.
srcStep	Source chrominance plane step.
pDstPlane	Pointer to the current macroblock that is reconstructed in U-plane and Y-plane.
dstStep	Destination chrominance plane step.
ppDstCoeff	Double pointer to the order of 8x8 blocks of residual coefficients for this macroblock, which are taken as a result of intra-prediction, forward transforming, and forward quantization (8x8 chrominance intra blocks, if the block is not zero-filled) in the same order as is shown in Figure 6-7 of [AVS]. The pointer is updated by the function and points to free space for the blocks for the next macroblock.
pPredModes	Pointer to the variable to store chrominance prediction mode for both subblocks. The function calculates the best prediction mode for each subblock, trying to save as much of visual information as possible. pPredModes [i] is defined in the same order as the coded subblocks go.
pChromaCBP	Pointer to the variable to store a coded block pattern. This value is calculated by the function. If *pChromaCBP & (1<<(1+ i))is not equal to 0 (0 ≤ i < 4), i-th 8x8 AC chroma block is not zero-filled and it exists in ppDstCoeff.
QP	Quantization parameter (CurrentQP in [AVS]), must be within range [0;51].
edgeType	Flag that specifies the availability of the macroblocks used for prediction. If the upper macroblock is not available for 8x8 intra prediction, edgeType&IPPVC_TOP_EDGE must be non-zero. If the left macroblock is not available for 8x8 intra prediction, edgeType&IPPVC_LEFT_EDGE must be non-zero. If the upper-left macroblock is not available for 8x8Intra prediction, edgeType&IPPVC_TOP_LEFT_EDGE must be non-zero. If the upper-right macroblock is not available for 8x8Intra prediction, edgeType&IPPVC_TOP_RIGHT_EDGE must be non-zero.

Description

The function ippiDisassembleChroma420Intra_AVS_16s8u_C1R is declared in the ippvc.h file. This function disassembles intra chroma macroblocks. The process for the 8x8 blocks in the same order as is shown in Figure 6‑7 of [AVS] is described below:

Perform intra prediction for an 8x8 chroma component in accordance with 9.4.2 of [AVS].
Perform subtraction of an 8x8 prediction block from an 8x8 source block.
Perform scaling, integer transformation, and forward shift for an 8x8 block.
Perform these steps for every available prediction modes for each block and save the best modes to a corresponding variable.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error condition if at least one of the specified pointers is NULL.
ippStsOutOfRangeErr	QP is less than 0 or greater than 51.