ref: 2b9a250fbda09220e480898421926d8ebdb498fd
dir: /codec/common/inc/golomb_common.h/
/*!
* \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 golomb_common.h
*
* \brief Exponential Golomb entropy coding/decoding routine
*
* \date 03/12/2015 Created
*
*************************************************************************************
*/
#ifndef EXPONENTIAL_GOLOMB_ENTROPY_CODING_COMMON_H__
#define EXPONENTIAL_GOLOMB_ENTROPY_CODING_COMMON_H__
#include "typedefs.h"
namespace WelsCommon {
#define WRITE_BE_32(ptr, val) do { \
(ptr)[0] = (val) >> 24; \
(ptr)[1] = (val) >> 16; \
(ptr)[2] = (val) >> 8; \
(ptr)[3] = (val) >> 0; \
} while (0)
/************************************************************************/
/* GOLOMB CODIMG FOR WELS COMMON */
/************************************************************************/
/*!
* \brief initialize bitstream writing
*
* \param pBs Bit string auxiliary pointer
* \param pBuf bit-stream pBuffer
* \param iSize iSize in bits for decoder; iSize in bytes for encoder
*
* \return iSize of pBuffer pData in byte; failed in -1 return
*/
static inline int32_t InitBits (SBitStringAux* pBs, const uint8_t* kpBuf, const int32_t kiSize) {
uint8_t* ptr = (uint8_t*)kpBuf;
pBs->pStartBuf = ptr;
pBs->pCurBuf = ptr;
pBs->pEndBuf = ptr + kiSize;
pBs->iLeftBits = 32;
pBs->uiCurBits = 0;
return kiSize;
}
static inline int32_t BsWriteBits (PBitStringAux pBitString, int32_t iLen, const uint32_t kuiValue) {
if (iLen < pBitString->iLeftBits) {
pBitString->uiCurBits = (pBitString->uiCurBits << iLen) | kuiValue;
pBitString->iLeftBits -= iLen;
} else {
iLen -= pBitString->iLeftBits;
pBitString->uiCurBits = (pBitString->uiCurBits << pBitString->iLeftBits) | (kuiValue >> iLen);
WRITE_BE_32 (pBitString->pCurBuf, pBitString->uiCurBits);
pBitString->pCurBuf += 4;
pBitString->uiCurBits = kuiValue & ((1 << iLen) - 1);
pBitString->iLeftBits = 32 - iLen;
}
return 0;
}
/*
* Write 1 bit
*/
static inline int32_t BsWriteOneBit (PBitStringAux pBitString, const uint32_t kuiValue) {
BsWriteBits (pBitString, 1, kuiValue);
return 0;
}
static inline int32_t BsFlush (PBitStringAux pBitString) {
WRITE_BE_32 (pBitString->pCurBuf, pBitString->uiCurBits << pBitString->iLeftBits);
pBitString->pCurBuf += 4 - pBitString->iLeftBits / 8;
pBitString->iLeftBits = 32;
pBitString->uiCurBits = 0;
return 0;
}
/*
* Write unsigned exp golomb codes
*/
static inline int32_t BsWriteUE (PBitStringAux pBitString, const uint32_t kuiValue) {
uint32_t iTmpValue = kuiValue + 1;
if (256 > kuiValue) {
BsWriteBits (pBitString, g_kuiGolombUELength[kuiValue], kuiValue + 1);
} else {
uint32_t n = 0;
if (iTmpValue & 0xffff0000) {
iTmpValue >>= 16;
n += 16;
}
if (iTmpValue & 0xff00) {
iTmpValue >>= 8;
n += 8;
}
//n += (g_kuiGolombUELength[iTmpValue] >> 1);
n += (g_kuiGolombUELength[iTmpValue - 1] >> 1);
BsWriteBits (pBitString, (n << 1) + 1, kuiValue + 1);
}
return 0;
}
/*
* Write signed exp golomb codes
*/
static inline int32_t BsWriteSE (PBitStringAux pBitString, const int32_t kiValue) {
uint32_t iTmpValue;
if (0 == kiValue) {
BsWriteOneBit (pBitString, 1);
} else if (0 < kiValue) {
iTmpValue = (kiValue << 1) - 1;
BsWriteUE (pBitString, iTmpValue);
} else {
iTmpValue = ((-kiValue) << 1);
BsWriteUE (pBitString, iTmpValue);
}
return 0;
}
/*
* Write RBSP trailing bits
*/
static inline int32_t BsRbspTrailingBits (PBitStringAux pBitString) {
BsWriteOneBit (pBitString, 1);
BsFlush (pBitString);
return 0;
}
}
#endif//EXPONENTIAL_GOLOMB_ENTROPY_CODING_COMMON_H__