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/**
*
* File Name: armVCM4P2_FillVLCBuffer.c
* OpenMAX DL: v1.0.2
* Revision: 9641
* Date: Thursday, February 7, 2008
*
* (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
*
*
*
* Description:
* Contains module for putting VLC bits
*
*/
#include "omxtypes.h"
#include "armOMX.h"
#include "armVC.h"
#include "armCOMM.h"
#include "armCOMM_Bitstream.h"
/**
* Function: armVCM4P2_FillVLCBuffer
*
* Description:
* Performs calculating the VLC bits depending on the escape type and insert
* the same in the bitstream
*
* Remarks:
*
* Parameters:
* [in] ppBitStream pointer to the pointer to the current byte in
* the bit stream
* [in] pBitOffset pointer to the bit position in the byte pointed
* by *ppBitStream. Valid within 0 to 7
* [in] run Run value (count of zeros) to be encoded
* [in] level Level value (non-zero value) to be encoded
* [in] runPlus Calculated as runPlus = run - (RMAX + 1)
* [in] levelPlus Calculated as
* levelPlus = sign(level)*[abs(level) - LMAX]
* [in] fMode Flag indicating the escape modes
* [in] last status of the last flag
* [in] maxRunForMultipleEntries
* The run value after which level will be equal to 1:
* (considering last and inter/intra status)
* [in] pRunIndexTable Run Index table defined in
* armVCM4P2_Huff_Tables_VLC.h
* [in] pVlcTable VLC table defined in armVCM4P2_Huff_Tables_VLC.h
* [out] ppBitStream *ppBitStream is updated after the block is encoded
* 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.
*
* Return Value:
* Standard OMXResult result. See enumeration for possible result codes.
*
*/
OMXResult armVCM4P2_FillVLCBuffer (
OMX_U8 **ppBitStream,
OMX_INT * pBitOffset,
OMX_U32 run,
OMX_S16 level,
OMX_U32 runPlus,
OMX_S16 levelPlus,
OMX_U8 fMode,
OMX_U8 last,
OMX_U8 maxRunForMultipleEntries,
const OMX_U8 *pRunIndexTable,
const ARM_VLC32 *pVlcTable
)
{
OMX_INT tempIndex;
OMX_U32 tempRun = run, sign = 0;
OMX_S16 tempLevel = level;
/* Escape sequence addition */
if (fMode == 1)
{
armPackBits(ppBitStream, pBitOffset, 3, 7);
armPackBits(ppBitStream, pBitOffset, 0, 1);
tempLevel = levelPlus;
}
else if(fMode == 2)
{
armPackBits(ppBitStream, pBitOffset, 3, 7);
armPackBits(ppBitStream, pBitOffset, 2, 2);
tempRun = runPlus;
}
else if (fMode == 3)
{
armPackBits(ppBitStream, pBitOffset, 3, 7);
armPackBits(ppBitStream, pBitOffset, 3, 2);
}
else if (fMode == 4)
{
armPackBits(ppBitStream, pBitOffset, 3, 7);
armPackBits(ppBitStream, pBitOffset, (OMX_U32)last, 1);
armPackBits(ppBitStream, pBitOffset, tempRun, 6);
if((tempLevel != 0) && (tempLevel != -128))
{
armPackBits(ppBitStream, pBitOffset,
(OMX_U32) tempLevel, 8);
}
return OMX_Sts_NoErr;
}
if (tempLevel < 0)
{
sign = 1;
tempLevel = armAbs(tempLevel);
}
/* Putting VLC bits in the stream */
if (fMode < 3)
{
if (tempRun > maxRunForMultipleEntries)
{
tempIndex = pRunIndexTable [maxRunForMultipleEntries + 1] +
(tempRun - maxRunForMultipleEntries - 1);
}
else
{
tempIndex = pRunIndexTable [tempRun] + (tempLevel -1);
}
armPackVLC32 (ppBitStream, pBitOffset,
pVlcTable [tempIndex]);
armPackBits(ppBitStream, pBitOffset, (OMX_U32)sign, 1);
}
else
{
if (sign)
{
tempLevel = -tempLevel;
}
tempRun = run;
armPackBits(ppBitStream, pBitOffset, (OMX_U32)last, 1);
armPackBits(ppBitStream, pBitOffset, tempRun, 6);
armPackBits(ppBitStream, pBitOffset, 1, 1);
armPackBits(ppBitStream, pBitOffset,
(OMX_U32) tempLevel, 12);
armPackBits(ppBitStream, pBitOffset, 1, 1);
}
return OMX_Sts_NoErr;
}
/*End of File*/
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