/*! * \copy *     Copyright (c)  2009-2013, 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. * * * \file	bit_stream.cpp * * \brief	Reading / writing bit-stream * * \date	03/10/2009 Created * ************************************************************************************* */#include "bit_stream.h"#include "error_code.h" namespace WelsDec { inline uint32_t GetValue4Bytes (uint8_t* pDstNal) {  uint32_t uiValue = 0;  uiValue = (pDstNal[0] << 24) | (pDstNal[1] << 16) | (pDstNal[2] << 8) | (pDstNal[3]);  return uiValue;} int32_t InitReadBits (PBitStringAux pBitString, intX_t iEndOffset) {  if(pBitString->pCurBuf>=(pBitString->pEndBuf - iEndOffset)) {    return ERR_INFO_INVALID_ACCESS;  }  pBitString->uiCurBits  = GetValue4Bytes (pBitString->pCurBuf);  pBitString->pCurBuf  += 4;  pBitString->iLeftBits = -16;  return ERR_NONE;} /*! * \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	0: success, other: fail */int32_t InitBits (PBitStringAux pBitString, const uint8_t* kpBuf, const int32_t kiSize) {  const int32_t kiSizeBuf = (kiSize + 7) >> 3;  uint8_t* pTmp = (uint8_t*)kpBuf;   if (NULL == pTmp)    return ERR_INFO_INVALID_ACCESS;   pBitString->pStartBuf   = pTmp;				// buffer to start position  pBitString->pEndBuf	    = pTmp + kiSizeBuf;	// buffer + length  pBitString->iBits	    = kiSize;				// count bits of overall bitstreaming inputindex;  pBitString->pCurBuf   = pBitString->pStartBuf;  int32_t iErr = InitReadBits (pBitString, 0);  if(iErr) {    return iErr;  }  return ERR_NONE;} } // namespace WelsDec