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/**
*
* File Name: omxVCM4P2_DecodeBlockCoef_Inter.c
* OpenMAX DL: v1.0.2
* Revision: 12290
* Date: Wednesday, April 9, 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
*
* Description:
* Decodes the INTER block coefficients. Inverse quantization, inversely zigzag
* positioning and IDCT, with appropriate clipping on each step, are performed
* 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.
*
* Remarks:
*
* Parameters:
* [in] ppBitStream pointer to the pointer to the current byte in
* the bit stream buffer. There is no boundary
* check for the bit stream buffer.
* [in] pBitOffset pointer to the bit position in the byte pointed
* to by *ppBitStream. *pBitOffset is valid within
* [0-7]
* [in] QP quantization parameter
* [in] shortVideoHeader a flag indicating presence of short_video_header;
* shortVideoHeader==1 indicates using quantization method defined in short
* video header mode, and shortVideoHeader==0 indicates normail quantization method.
* [out] ppBitStream *ppBitStream is updated after the block is decoded, so that it points to the
* current byte in the bit stream buffer.
* [out] pBitOffset *pBitOffset is updated so that it points to the current bit position in the
* byte pointed by *ppBitStream
* [out] pDst pointer to the decoded residual buffer (a contiguous array of 64 elements of
* OMX_S16 data type). Must be 16-byte aligned.
*
* Return Value:
* OMX_Sts_NoErr - no error
* OMX_Sts_BadArgErr - bad arguments
* - At least one of the following pointers is Null: ppBitStream, *ppBitStream, pBitOffset , pDst
* - At least one of the below case:
* - *pBitOffset exceeds [0,7], QP <= 0;
* - pDst not 16-byte aligned
* OMX_Sts_Err - status error
*
*/
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);
/* 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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