ref: 3ccd2ae4cf47d6099737d1a842a67edc4c42ea74
dir: /codec/decoder/core/inc/dec_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"
//#include <assert.h>
#include "ls_defines.h"
#include "error_code.h"
namespace WelsDec {
#define WELS_READ_VERIFY(uiRet) { \
if( uiRet != ERR_NONE ) \
return uiRet; \
}
#define GET_WORD(iCurBits, pBufPtr, iLeftBits, iAllowedBytes, iReadBytes) { \
if (iReadBytes > iAllowedBytes+1) { \
return ERR_INFO_READ_OVERFLOW; \
} \
iCurBits |= ((uint32_t)((pBufPtr[0] << 8) | pBufPtr[1])) << (iLeftBits); \
iLeftBits -= 16; \
pBufPtr +=2; \
}
#define NEED_BITS(iCurBits, pBufPtr, iLeftBits, iAllowedBytes, iReadBytes) { \
if( iLeftBits > 0 ) { \
GET_WORD(iCurBits, pBufPtr, iLeftBits, iAllowedBytes, iReadBytes); \
} \
}
#define UBITS(iCurBits, iNumBits) (iCurBits>>(32-(iNumBits)))
#define DUMP_BITS(iCurBits, pBufPtr, iLeftBits, iNumBits, iAllowedBytes, iReadBytes) { \
iCurBits <<= (iNumBits); \
iLeftBits += (iNumBits); \
NEED_BITS(iCurBits, pBufPtr, iLeftBits, iAllowedBytes, iReadBytes); \
}
static inline int32_t BsGetBits (PBitStringAux pBs, int32_t iNumBits, uint32_t* pCode) {
int32_t iRc = UBITS (pBs->uiCurBits, iNumBits);
int32_t iAllowedBytes = pBs->pEndBuf - pBs->pStartBuf; //actual stream bytes
int32_t iReadBytes = pBs->pCurBuf - pBs->pStartBuf;
DUMP_BITS (pBs->uiCurBits, pBs->pCurBuf, pBs->iLeftBits, iNumBits, iAllowedBytes, iReadBytes);
*pCode = iRc;
return ERR_NONE;
}
/*
* Exponential Golomb codes decoding routines
*/
// for data sharing cross modules and try to reduce size of binary generated, 12/10/2009
extern const uint8_t g_kuiIntra4x4CbpTable[48];
extern const uint8_t g_kuiInterCbpTable[48];
extern const uint8_t g_kuiLeadingZeroTable[256];
static const uint32_t g_kuiPrefix8BitsTable[16] = {
0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3
};
static inline uint32_t GetPrefixBits (uint32_t uiValue) {
uint32_t iNumBit = 0;
if (uiValue & 0xffff0000) {
uiValue >>= 16;
iNumBit += 16;
}
if (uiValue & 0xff00) {
uiValue >>= 8;
iNumBit += 8;
}
if (uiValue & 0xf0) {
uiValue >>= 4;
iNumBit += 4;
}
iNumBit += g_kuiPrefix8BitsTable[uiValue];
return (32 - iNumBit);
}
/*
* Read one bit from bit stream followed
*/
static inline uint32_t BsGetOneBit (PBitStringAux pBs, uint32_t* pCode) {
return (BsGetBits (pBs, 1, pCode));
}
static inline int32_t GetLeadingZeroBits (uint32_t iCurBits) { //<=32 bits
uint32_t uiValue;
uiValue = UBITS (iCurBits, 8); //ShowBits( bs, 8 );
if (uiValue) {
return g_kuiLeadingZeroTable[uiValue];
}
uiValue = UBITS (iCurBits, 16); //ShowBits( bs, 16 );
if (uiValue) {
return (g_kuiLeadingZeroTable[uiValue] + 8);
}
uiValue = UBITS (iCurBits, 24); //ShowBits( bs, 24 );
if (uiValue) {
return (g_kuiLeadingZeroTable[uiValue] + 16);
}
uiValue = iCurBits; //ShowBits( bs, 32 );
if (uiValue) {
return (g_kuiLeadingZeroTable[uiValue] + 24);
}
//ASSERT(false); // should not go here
return -1;
}
static inline uint32_t BsGetUe (PBitStringAux pBs, uint32_t* pCode) {
uint32_t iValue = 0;
int32_t iLeadingZeroBits = GetLeadingZeroBits (pBs->uiCurBits);
int32_t iAllowedBytes, iReadBytes;
iAllowedBytes = pBs->pEndBuf - pBs->pStartBuf; //actual stream bytes
if (iLeadingZeroBits == -1) { //bistream error
return ERR_INFO_READ_LEADING_ZERO;//-1
} else if (iLeadingZeroBits >
16) { //rarely into this condition (even may be bitstream error), prevent from 16-bit reading overflow
//using two-step reading instead of one time reading of >16 bits.
iReadBytes = pBs->pCurBuf - pBs->pStartBuf;
DUMP_BITS (pBs->uiCurBits, pBs->pCurBuf, pBs->iLeftBits, 16, iAllowedBytes, iReadBytes);
iReadBytes = pBs->pCurBuf - pBs->pStartBuf;
DUMP_BITS (pBs->uiCurBits, pBs->pCurBuf, pBs->iLeftBits, iLeadingZeroBits + 1 - 16, iAllowedBytes, iReadBytes);
} else {
iReadBytes = pBs->pCurBuf - pBs->pStartBuf;
DUMP_BITS (pBs->uiCurBits, pBs->pCurBuf, pBs->iLeftBits, iLeadingZeroBits + 1, iAllowedBytes, iReadBytes);
}
if (iLeadingZeroBits) {
iValue = UBITS (pBs->uiCurBits, iLeadingZeroBits);
iReadBytes = pBs->pCurBuf - pBs->pStartBuf;
DUMP_BITS (pBs->uiCurBits, pBs->pCurBuf, pBs->iLeftBits, iLeadingZeroBits, iAllowedBytes, iReadBytes);
}
*pCode = ((1 << iLeadingZeroBits) - 1 + iValue);
return ERR_NONE;
}
/*
* Read signed exp golomb codes
*/
static inline int32_t BsGetSe (PBitStringAux pBs, int32_t* pCode) {
uint32_t uiCodeNum;
WELS_READ_VERIFY (BsGetUe (pBs, &uiCodeNum));
if (uiCodeNum & 0x01) {
*pCode = (int32_t) ((uiCodeNum + 1) >> 1);
} else {
*pCode = NEG_NUM ((int32_t) (uiCodeNum >> 1));
}
return ERR_NONE;
}
/*
* Get unsigned truncated exp golomb code.
*/
static inline int32_t BsGetTe0 (PBitStringAux pBs, int32_t iRange, uint32_t* pCode) {
if (iRange == 1) {
*pCode = 0;
} else if (iRange == 2) {
WELS_READ_VERIFY (BsGetOneBit (pBs, pCode));
*pCode ^= 1;
} else {
WELS_READ_VERIFY (BsGetUe (pBs, pCode));
}
return ERR_NONE;
}
/*
* Get number of trailing bits
*/
static inline int32_t BsGetTrailingBits (uint8_t* pBuf) {
// TODO
uint32_t uiValue = *pBuf;
int32_t iRetNum = 1;
do {
if (uiValue & 1)
return iRetNum;
uiValue >>= 1;
++ iRetNum;
} while (iRetNum < 9);
return 0;
}
//define macros to check syntax elements
#define WELS_CHECK_SE_BOTH_ERROR(val, lower_bound, upper_bound, syntax_name, ret_code) do {\
if ((val < lower_bound) || (val > upper_bound)) {\
WelsLog(pCtx, WELS_LOG_ERROR, "invalid syntax " syntax_name " %d\n", val);\
return ret_code;\
}\
}while(0)
#define WELS_CHECK_SE_LOWER_ERROR(val, lower_bound, syntax_name, ret_code) do {\
if (val < lower_bound) {\
WelsLog(pCtx, WELS_LOG_ERROR, "invalid syntax " syntax_name " %d\n", val);\
return ret_code;\
}\
}while(0)
#define WELS_CHECK_SE_UPPER_ERROR(val, upper_bound, syntax_name, ret_code) do {\
if (val > upper_bound) {\
WelsLog(pCtx, WELS_LOG_ERROR, "invalid syntax " syntax_name " %d\n", val);\
return ret_code;\
}\
}while(0)
#define WELS_CHECK_SE_BOTH_ERROR_NOLOG(val, lower_bound, upper_bound, syntax_name, ret_code) do {\
if ((val < lower_bound) || (val > upper_bound)) {\
return ret_code;\
}\
}while(0)
#define WELS_CHECK_SE_LOWER_ERROR_NOLOG(val, lower_bound, syntax_name, ret_code) do {\
if (val < lower_bound) {\
return ret_code;\
}\
}while(0)
#define WELS_CHECK_SE_UPPER_ERROR_NOLOG(val, upper_bound, syntax_name, ret_code) do {\
if (val > upper_bound) {\
return ret_code;\
}\
}while(0)
#define WELS_CHECK_SE_BOTH_WARNING(val, lower_bound, upper_bound, syntax_name) do {\
if ((val < lower_bound) || (val > upper_bound)) {\
WelsLog(pCtx, WELS_LOG_WARNING, "invalid syntax " syntax_name " %d\n", val);\
}\
}while(0)
#define WELS_CHECK_SE_LOWER_WARNING(val, lower_bound, syntax_name) do {\
if (val < lower_bound) {\
WelsLog(pCtx, WELS_LOG_WARNING, "invalid syntax " syntax_name " %d\n", val);\
}\
}while(0)
#define WELS_CHECK_SE_UPPER_WARNING(val, upper_bound, syntax_name) do {\
if (val > upper_bound) {\
WelsLog(pCtx, WELS_LOG_WARNING, "invalid syntax " syntax_name " %d\n", val);\
}\
}while(0)
// below define syntax element offset
// for bit_depth_luma_minus8 and bit_depth_chroma_minus8
#define BIT_DEPTH_LUMA_OFFSET 8
#define BIT_DEPTH_CHROMA_OFFSET 8
// for log2_max_frame_num_minus4
#define LOG2_MAX_FRAME_NUM_OFFSET 4
// for log2_max_pic_order_cnt_lsb_minus4
#define LOG2_MAX_PIC_ORDER_CNT_LSB_OFFSET 4
// for pic_width_in_mbs_minus1
#define PIC_WIDTH_IN_MBS_OFFSET 1
// for pic_height_in_map_units_minus1
#define PIC_HEIGHT_IN_MAP_UNITS_OFFSET 1
// for bit_depth_aux_minus8
#define BIT_DEPTH_AUX_OFFSET 8
// for num_slice_groups_minus1
#define NUM_SLICE_GROUPS_OFFSET 1
// for run_length_minus1
#define RUN_LENGTH_OFFSET 1
// for slice_group_change_rate_minus1
#define SLICE_GROUP_CHANGE_RATE_OFFSET 1
// for pic_size_in_map_units_minus1
#define PIC_SIZE_IN_MAP_UNITS_OFFSET 1
// for num_ref_idx_l0_default_active_minus1 and num_ref_idx_l1_default_active_minus1
#define NUM_REF_IDX_L0_DEFAULT_ACTIVE_OFFSET 1
#define NUM_REF_IDX_L1_DEFAULT_ACTIVE_OFFSET 1
// for pic_init_qp_minus26 and pic_init_qs_minus26
#define PIC_INIT_QP_OFFSET 26
#define PIC_INIT_QS_OFFSET 26
// for num_ref_idx_l0_active_minus1 and num_ref_idx_l1_active_minus1
#define NUM_REF_IDX_L0_ACTIVE_OFFSET 1
#define NUM_REF_IDX_L1_ACTIVE_OFFSET 1
// From Level 5.2
#define MAX_MB_SIZE 36864
} // namespace WelsDec
#endif//WELS_EXPONENTIAL_GOLOMB_ENTROPY_CODING_H__