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/*
* Copyright (C) 2007-2008 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
/**
*
* File Name: omxVCM4P2_DecodeVLCZigzag_Inter.c
* OpenMAX DL: v1.0.2
* Revision: 9641
* Date: Thursday, February 7, 2008
*
*
*
*
* Description:
* Contains modules for zigzag scanning and VLC decoding
* for inter block.
*
*/
#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: omxVCM4P2_DecodeVLCZigzag_Inter (6.2.5.2.3)
*
* Description:
* Performs VLC decoding and inverse zigzag scan for one inter-coded block.
*
* Input Arguments:
*
* ppBitStream - double pointer to the current byte in the stream buffer
* pBitOffset - pointer to the next available bit in the current stream
* byte referenced by *ppBitStream. The parameter *pBitOffset is
* valid within the range [0-7].
* shortVideoHeader - binary flag indicating presence of
* short_video_header; escape modes 0-3 are used if
* shortVideoHeader==0, and escape mode 4 is used when
* shortVideoHeader==1.
*
* Output Arguments:
*
* ppBitStream - *ppBitStream is updated after the block is decoded such
* that it points to the current byte in the stream buffer
* pBitOffset - *pBitOffset is updated after decoding such that it points
* to the next available bit in the stream byte referenced by
* *ppBitStream
* pDst - pointer to the coefficient buffer of current block; must be
* 4-byte aligned.
*
* Return Value:
*
* OMX_Sts_BadArgErr - bad arguments:
* - At least one of the following pointers is NULL:
* ppBitStream, *ppBitStream, pBitOffset, pDst
* - pDst is not 4-byte aligned
* - *pBitOffset exceeds [0,7]
* OMX_Sts_Err - status error, if:
* - At least one mark bit is equal to zero
* - Encountered an illegal stream code that cannot be found in the VLC table
* - Encountered an illegal code in the VLC FLC table
* - The number of coefficients is greater than 64
*
*/
OMXResult omxVCM4P2_DecodeVLCZigzag_Inter(
const OMX_U8 ** ppBitStream,
OMX_INT * pBitOffset,
OMX_S16 * pDst,
OMX_INT shortVideoHeader
)
{
OMX_U8 last,start = 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);
errorCode = armVCM4P2_GetVLCBits (
ppBitStream,
pBitOffset,
pDst,
shortVideoHeader,
start,
&last,
11,
42,
2,
5,
armVCM4P2_InterL0RunIdx,
armVCM4P2_InterVlcL0,
armVCM4P2_InterL1RunIdx,
armVCM4P2_InterVlcL1,
armVCM4P2_InterL0LMAX,
armVCM4P2_InterL1LMAX,
armVCM4P2_InterL0RMAX,
armVCM4P2_InterL1RMAX,
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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