ref: a0320dac5d0eea33be9d7dd3b226598e4dadcf48
dir: /codec/encoder/core/inc/svc_enc_golomb.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.h
*
* \brief Exponential Golomb entropy coding/decoding routine
*
* \date 03/13/2009 Created
*
*************************************************************************************
*/
#ifndef WELS_EXPONENTIAL_GOLOMB_ENTROPY_CODING_H__
#define WELS_EXPONENTIAL_GOLOMB_ENTROPY_CODING_H__
#include "typedefs.h"
#include "bit_stream.h"
#include "macros.h"
namespace WelsSVCEnc {
#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 ENCODER */
/************************************************************************/
/*
* Exponential Golomb codes encoding routines
*/
#define CAVLC_BS_INIT( pBs ) \
uint8_t * pBufPtr = pBs->pBufPtr; \
uint32_t uiCurBits = pBs->uiCurBits; \
int32_t iLeftBits = pBs->iLeftBits;
#define CAVLC_BS_UNINIT( pBs ) \
pBs->pBufPtr = pBufPtr; \
pBs->uiCurBits = uiCurBits; \
pBs->iLeftBits = iLeftBits;
#define CAVLC_BS_WRITE( n, v ) \
{ \
if ( (n) < iLeftBits ) {\
uiCurBits = (uiCurBits<<(n))|(v);\
iLeftBits -= (n);\
}\
else {\
(n) -= iLeftBits;\
uiCurBits = (uiCurBits<<iLeftBits) | ((v)>>(n));\
WRITE_BE_32(pBufPtr, uiCurBits);\
pBufPtr += 4;\
uiCurBits = (v) & ((1<<(n))-1);\
iLeftBits = 32 - (n);\
}\
} ;
extern const uint32_t g_uiGolombUELength[256];
/*
* Get size of unsigned exp golomb codes
*/
static inline uint32_t BsSizeUE (const uint32_t kiValue) {
if (256 > kiValue) {
return g_uiGolombUELength[kiValue];
} else {
uint32_t n = 0;
uint32_t iTmpValue = kiValue + 1;
if (iTmpValue & 0xffff0000) {
iTmpValue >>= 16;
n += 16;
}
if (iTmpValue & 0xff00) {
iTmpValue >>= 8;
n += 8;
}
//n += (g_uiGolombUELength[iTmpValue] >> 1);
n += (g_uiGolombUELength[iTmpValue - 1] >> 1);
return ((n << 1) + 1);
}
}
/*
* Get size of signed exp golomb codes
*/
static inline uint32_t BsSizeSE (const int32_t kiValue) {
uint32_t iTmpValue;
if (0 == kiValue) {
return 1;
} else if (0 < kiValue) {
iTmpValue = (kiValue << 1) - 1;
return BsSizeUE (iTmpValue);
} else {
iTmpValue = ((-kiValue) << 1);
return BsSizeUE (iTmpValue);
}
}
/*
* Get size of truncated exp golomb codes
*/
static inline int32_t BsSizeTE (const int32_t kiX, const int32_t kiValue) {
return 0;
}
static inline int32_t BsWriteBits (SBitStringAux* pBs, int32_t n, const uint32_t kuiValue) {
if (n < pBs->iLeftBits) {
pBs->uiCurBits = (pBs->uiCurBits << n) | kuiValue;
pBs->iLeftBits -= n;
} else {
n -= pBs->iLeftBits;
pBs->uiCurBits = (pBs->uiCurBits << pBs->iLeftBits) | (kuiValue >> n);
WRITE_BE_32 (pBs->pBufPtr, pBs->uiCurBits);
pBs->pBufPtr += 4;
pBs->uiCurBits = kuiValue & ((1 << n) - 1);
pBs->iLeftBits = 32 - n;
}
return 0;
}
/*
* Write 1 bit
*/
static inline int32_t BsWriteOneBit (SBitStringAux* pBs, const uint32_t kuiValue) {
BsWriteBits (pBs, 1, kuiValue);
return 0;
}
static inline void BsFlush (SBitStringAux* pBs) {
WRITE_BE_32 (pBs->pBufPtr, pBs->uiCurBits << pBs->iLeftBits);
pBs->pBufPtr += 4 - pBs->iLeftBits / 8;
pBs->iLeftBits = 32;
pBs->uiCurBits = 0; // for future writing safe, 5/19/2010
}
/*
* Write unsigned exp golomb codes
*/
static inline void BsWriteUE (SBitStringAux* pBs, const uint32_t kuiValue) {
uint32_t iTmpValue = kuiValue + 1;
if (256 > kuiValue) {
BsWriteBits (pBs, g_uiGolombUELength[kuiValue], kuiValue + 1);
} else {
uint32_t n = 0;
if (iTmpValue & 0xffff0000) {
iTmpValue >>= 16;
n += 16;
}
if (iTmpValue & 0xff00) {
iTmpValue >>= 8;
n += 8;
}
//n += (g_uiGolombUELength[iTmpValue] >> 1);
n += (g_uiGolombUELength[iTmpValue - 1] >> 1);
BsWriteBits (pBs, (n << 1) + 1, kuiValue + 1);
}
return;
}
/*
* Write signed exp golomb codes
*/
static inline void BsWriteSE (SBitStringAux* pBs, int32_t iValue) {
uint32_t iTmpValue;
if (0 == iValue) {
BsWriteOneBit (pBs, 1);
} else if (0 < iValue) {
iTmpValue = (iValue << 1) - 1;
BsWriteUE (pBs, iTmpValue);
} else {
iTmpValue = ((-iValue) << 1);
BsWriteUE (pBs, iTmpValue);
}
return;
}
/*
* Write truncated exp golomb codes
*/
static inline void BsWriteTE (SBitStringAux* pBs, const int32_t kiX, const uint32_t kuiValue) {
if (1 == kiX) {
BsWriteOneBit (pBs, !kuiValue);
} else {
BsWriteUE (pBs, kuiValue);
}
}
/*
* Write RBSP trailing bits
*/
static inline void BsRbspTrailingBits (SBitStringAux* pBs) {
BsWriteOneBit (pBs, 1);
BsFlush (pBs);
}
static inline bool BsCheckByteAlign (SBitStringAux* pBs) {
return ! (pBs->iLeftBits & 0x7);
}
static inline int32_t BsGetBitsPos (SBitStringAux* pBs) {
return (int32_t) (((pBs->pBufPtr - pBs->pBuf) << 3) + 32 - pBs->iLeftBits);
}
}
#endif//WELS_EXPONENTIAL_GOLOMB_ENTROPY_CODING_H__