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/**
*
* File Name: omxVCM4P2_DecodeBlockCoef_Inter.c
* OpenMAX DL: v1.0.2
* Revision: 9641
* Date: Thursday, February 7, 2008
*
* (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
*
*
*
* Description:
* Contains modules for inter reconstruction
*
*/
#include "omxtypes.h"
#include "armOMX.h"
#include "omxVC.h"
#include "armCOMM.h"
/**
* Function: omxVCM4P2_DecodeBlockCoef_Inter (6.2.5.4.2)
*
* Description:
* Decodes the INTER block coefficients. This function performs inverse
* quantization, inverse zigzag positioning, and IDCT (with appropriate
* clipping on each step) on the coefficients. The results (residuals) are
* placed in a contiguous array of 64 elements. For INTER block, the output
* buffer holds the residuals for further reconstruction.
*
* Input Arguments:
*
* ppBitStream - pointer to the pointer to the current byte in the bit
* stream buffer. There is no boundary check for the bit stream
* buffer.
* pBitOffset - pointer to the bit position in the byte pointed to by
* *ppBitStream. *pBitOffset is valid within [0-7]
* QP - quantization parameter
* shortVideoHeader - binary flag indicating presence of
* short_video_header; shortVideoHeader==1 selects linear intra DC
* mode, and shortVideoHeader==0 selects non linear intra DC mode.
*
* Output Arguments:
*
* ppBitStream - *ppBitStream is updated after the block is decoded, so
* that it points to the current byte in the bit stream buffer
* pBitOffset - *pBitOffset is updated so that it points to the current bit
* position in the byte pointed by *ppBitStream
* pDst - pointer to the decoded residual buffer (a contiguous array of 64
* elements of OMX_S16 data type); must be aligned on a 16-byte
* boundary.
*
* Return Value:
*
* OMX_Sts_NoErr - no error
* OMX_Sts_BadArgErr - bad arguments, if:
* - At least one of the following pointers is Null:
* ppBitStream, *ppBitStream, pBitOffset , pDst
* - *pBitOffset exceeds [0,7]
* - QP <= 0.
* - pDst is not 16-byte aligned
* OMX_Sts_Err - status error. Refer to OMX_Sts_Err of DecodeVLCZigzag_Inter .
*
*/
OMXResult omxVCM4P2_DecodeBlockCoef_Inter(
const OMX_U8 ** ppBitStream,
OMX_INT * pBitOffset,
OMX_S16 * pDst,
OMX_INT QP,
OMX_INT shortVideoHeader
)
{
/* 64 elements are needed but to align it to 16 bytes need
15 more elements of padding */
OMX_S16 tempBuf[79];
OMX_S16 *pTempBuf1;
OMXResult errorCode;
/* Aligning the local buffers */
pTempBuf1 = armAlignTo16Bytes(tempBuf);
/* Argument error checks */
armRetArgErrIf(ppBitStream == NULL, OMX_Sts_BadArgErr);
armRetArgErrIf(*ppBitStream == NULL, OMX_Sts_BadArgErr);
armRetArgErrIf(pBitOffset == NULL, OMX_Sts_BadArgErr);
armRetArgErrIf(pDst == NULL, OMX_Sts_BadArgErr);
armRetArgErrIf(!armIs16ByteAligned(pDst), OMX_Sts_BadArgErr);
armRetArgErrIf(((QP <= 0) || (QP >= 32)), OMX_Sts_BadArgErr);
armRetArgErrIf(((*pBitOffset < 0) || (*pBitOffset > 7)), OMX_Sts_BadArgErr);
/* VLD and zigzag */
errorCode = omxVCM4P2_DecodeVLCZigzag_Inter(ppBitStream, pBitOffset,
pTempBuf1,shortVideoHeader);
armRetDataErrIf((errorCode != OMX_Sts_NoErr), errorCode);
/* Dequantization */
errorCode = omxVCM4P2_QuantInvInter_I(
pTempBuf1,
QP);
armRetDataErrIf((errorCode != OMX_Sts_NoErr), errorCode);
/* Inverse transform */
errorCode = omxVCM4P2_IDCT8x8blk(pTempBuf1, pDst);
armRetDataErrIf((errorCode != OMX_Sts_NoErr), errorCode);
return OMX_Sts_NoErr;
}
/* End of file */
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