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/**
*
* File Name: armVCM4P2_DecodeVLCZigzag_intra.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 filling of the coefficient buffer
*
*/
#include "omxtypes.h"
#include "armOMX.h"
#include "omxVC.h"
#include "armVC.h"
#include "armCOMM_Bitstream.h"
#include "armCOMM.h"
#include "armVCM4P2_Huff_Tables_VLC.h"
#include "armVCM4P2_ZigZag_Tables.h"
/**
* Function: armVCM4P2_DecodeVLCZigzag_Intra
*
* Description:
* Performs VLC decoding and inverse zigzag scan for one intra coded block.
*
* Remarks:
*
* Parameters:
* [in] ppBitStream pointer to the pointer to the current byte in
* the bitstream buffer
* [in] pBitOffset pointer to the bit position in the byte pointed
* to by *ppBitStream. *pBitOffset is valid within
* [0-7].
* [in] predDir AC prediction direction which is used to decide
* the zigzag scan pattern. It takes one of the
* following values:
* OMX_VC_NONE AC prediction not used;
* perform classical zigzag scan;
* OMX_VC_HORIZONTAL Horizontal prediction;
* perform alternate-vertical
* zigzag scan;
* OMX_VC_VERTICAL Vertical prediction;
* thus perform
* alternate-horizontal
* zigzag scan.
* [in] start start indicates whether the encoding begins with 0th element
* or 1st.
* [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 coefficient buffer of current
* block. Should be 32-bit aligned
*
* Return Value:
* Standard OMXResult result. See enumeration for possible result codes.
*
*/
OMXResult armVCM4P2_DecodeVLCZigzag_Intra(
const OMX_U8 ** ppBitStream,
OMX_INT * pBitOffset,
OMX_S16 * pDst,
OMX_U8 predDir,
OMX_INT shortVideoHeader,
OMX_U8 start
)
{
OMX_U8 last = 0;
const OMX_U8 *pZigzagTable = armVCM4P2_aClassicalZigzagScan;
OMXResult errorCode;
/* 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(!armIs4ByteAligned(pDst), OMX_Sts_BadArgErr);
armRetArgErrIf((*pBitOffset < 0) || (*pBitOffset >7), OMX_Sts_BadArgErr);
armRetArgErrIf((predDir > 2), OMX_Sts_BadArgErr);
switch (predDir)
{
case OMX_VC_NONE:
{
pZigzagTable = armVCM4P2_aClassicalZigzagScan;
break;
}
case OMX_VC_HORIZONTAL:
{
pZigzagTable = armVCM4P2_aVerticalZigzagScan;
break;
}
case OMX_VC_VERTICAL:
{
pZigzagTable = armVCM4P2_aHorizontalZigzagScan;
break;
}
}
errorCode = armVCM4P2_GetVLCBits (
ppBitStream,
pBitOffset,
pDst,
shortVideoHeader,
start,
&last,
10,
62,
7,
21,
armVCM4P2_IntraL0RunIdx,
armVCM4P2_IntraVlcL0,
armVCM4P2_IntraL1RunIdx,
armVCM4P2_IntraVlcL1,
armVCM4P2_IntraL0LMAX,
armVCM4P2_IntraL1LMAX,
armVCM4P2_IntraL0RMAX,
armVCM4P2_IntraL1RMAX,
pZigzagTable );
armRetDataErrIf((errorCode != OMX_Sts_NoErr), errorCode);
if (last == 0)
{
return OMX_Sts_Err;
}
return OMX_Sts_NoErr;
}
/* End of file */
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