openh264/codec/decoder/core/inc/bit_stream.h
2014-11-24 00:04:36 -08:00

81 lines
3.3 KiB
C++

/*!
* \copy
* Copyright (c) 2004-2013, Cisco Systems
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
//bit_stream.h - bit-stream reading and / writing auxiliary data
#ifndef WELS_BIT_STREAM_H__
#define WELS_BIT_STREAM_H__
#include "typedefs.h"
namespace WelsDec {
/*
* Bit-stream auxiliary reading / writing
*/
typedef struct TagBitStringAux {
uint8_t* pStartBuf; // buffer to start position
uint8_t* pEndBuf; // buffer + length
int32_t iBits; // count bits of overall bitstreaming input
intX_t iIndex; //only for cavlc usage
uint8_t* pCurBuf; // current reading position
uint32_t uiCurBits;
int32_t iLeftBits; // count number of available bits left ([1, 8]),
// need pointer to next byte start position in case 0 bit left then 8 instead
} SBitStringAux, *PBitStringAux;
/*!
* \brief input bits for decoder or initialize bitstream writing in encoder
*
* \param pBitString Bit string auxiliary pointer
* \param kpBuf bit-stream buffer
* \param kiSize size in bits for decoder; size in bytes for encoder
*
* \return size of buffer data in byte; failed in -1 return
*/
int32_t InitBits (PBitStringAux pBitString, const uint8_t* kpBuf, const int32_t kiSize);
int32_t InitReadBits (PBitStringAux pBitString, intX_t iEndOffset);
//The following for writing bs in decoder for Parse Only purpose
void DecInitBitsForEncoding (PBitStringAux pBitString, uint8_t* kpBuf, const int32_t kiSize);
int32_t DecBsWriteBits (PBitStringAux pBitString, int32_t iLen, const uint32_t kuiValue);
int32_t DecBsWriteOneBit (PBitStringAux pBitString, const uint32_t kuiValue);
int32_t DecBsFlush (PBitStringAux pBitString);
int32_t DecBsWriteUe (PBitStringAux pBitString, const uint32_t kuiValue);
int32_t DecBsWriteSe (PBitStringAux pBitString, const int32_t kiValue);
int32_t DecBsRbspTrailingBits (PBitStringAux pBitString);
void RBSP2EBSP (uint8_t* pDstBuf, uint8_t* pSrcBuf, const int32_t kiSize);
} // namespace WelsDec
#endif//WELS_BIT_STREAM_H__