1 /*!
2 * \copy
3 * Copyright (c) 2009-2013, Cisco Systems
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * * Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * * Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
26 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
28 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 *
31 *
32 * \file golomb_common.h
33 *
34 * \brief Exponential Golomb entropy coding/decoding routine
35 *
36 * \date 03/12/2015 Created
37 *
38 *************************************************************************************
39 */
40 #ifndef EXPONENTIAL_GOLOMB_ENTROPY_CODING_COMMON_H__
41 #define EXPONENTIAL_GOLOMB_ENTROPY_CODING_COMMON_H__
42
43 #include "typedefs.h"
44
45 namespace WelsCommon {
46
47 #define WRITE_BE_32(ptr, val) do { \
48 (ptr)[0] = (val) >> 24; \
49 (ptr)[1] = (val) >> 16; \
50 (ptr)[2] = (val) >> 8; \
51 (ptr)[3] = (val) >> 0; \
52 } while (0)
53 /************************************************************************/
54 /* GOLOMB CODIMG FOR WELS COMMON */
55 /************************************************************************/
56
57
58 /*!
59 * \brief initialize bitstream writing
60 *
61 * \param pBs Bit string auxiliary pointer
62 * \param pBuf bit-stream pBuffer
63 * \param iSize iSize in bits for decoder; iSize in bytes for encoder
64 *
65 * \return iSize of pBuffer pData in byte; failed in -1 return
66 */
InitBits(SBitStringAux * pBs,const uint8_t * kpBuf,const int32_t kiSize)67 static inline int32_t InitBits (SBitStringAux* pBs, const uint8_t* kpBuf, const int32_t kiSize) {
68 uint8_t* ptr = (uint8_t*)kpBuf;
69
70 pBs->pStartBuf = ptr;
71 pBs->pCurBuf = ptr;
72 pBs->pEndBuf = ptr + kiSize;
73 pBs->iLeftBits = 32;
74 pBs->uiCurBits = 0;
75
76 return kiSize;
77 }
78
BsWriteBits(PBitStringAux pBitString,int32_t iLen,const uint32_t kuiValue)79 static inline int32_t BsWriteBits (PBitStringAux pBitString, int32_t iLen, const uint32_t kuiValue) {
80 if (iLen < pBitString->iLeftBits) {
81 pBitString->uiCurBits = (pBitString->uiCurBits << iLen) | kuiValue;
82 pBitString->iLeftBits -= iLen;
83 } else {
84 iLen -= pBitString->iLeftBits;
85 pBitString->uiCurBits = (pBitString->uiCurBits << pBitString->iLeftBits) | (kuiValue >> iLen);
86 WRITE_BE_32 (pBitString->pCurBuf, pBitString->uiCurBits);
87 pBitString->pCurBuf += 4;
88 pBitString->uiCurBits = kuiValue & ((1 << iLen) - 1);
89 pBitString->iLeftBits = 32 - iLen;
90 }
91 return 0;
92 }
93
94 /*
95 * Write 1 bit
96 */
BsWriteOneBit(PBitStringAux pBitString,const uint32_t kuiValue)97 static inline int32_t BsWriteOneBit (PBitStringAux pBitString, const uint32_t kuiValue) {
98 BsWriteBits (pBitString, 1, kuiValue);
99 return 0;
100 }
101
BsFlush(PBitStringAux pBitString)102 static inline int32_t BsFlush (PBitStringAux pBitString) {
103 WRITE_BE_32 (pBitString->pCurBuf, pBitString->uiCurBits << pBitString->iLeftBits);
104 pBitString->pCurBuf += 4 - pBitString->iLeftBits / 8;
105 pBitString->iLeftBits = 32;
106 pBitString->uiCurBits = 0;
107 return 0;
108 }
109
110 /*
111 * Write unsigned exp golomb codes
112 */
113
BsWriteUE(PBitStringAux pBitString,const uint32_t kuiValue)114 static inline int32_t BsWriteUE (PBitStringAux pBitString, const uint32_t kuiValue) {
115 uint32_t iTmpValue = kuiValue + 1;
116 if (256 > kuiValue) {
117 BsWriteBits (pBitString, g_kuiGolombUELength[kuiValue], kuiValue + 1);
118 } else {
119 uint32_t n = 0;
120 if (iTmpValue & 0xffff0000) {
121 iTmpValue >>= 16;
122 n += 16;
123 }
124 if (iTmpValue & 0xff00) {
125 iTmpValue >>= 8;
126 n += 8;
127 }
128
129 //n += (g_kuiGolombUELength[iTmpValue] >> 1);
130
131 n += (g_kuiGolombUELength[iTmpValue - 1] >> 1);
132 BsWriteBits (pBitString, (n << 1) + 1, kuiValue + 1);
133 }
134 return 0;
135 }
136
137 /*
138 * Write signed exp golomb codes
139 */
BsWriteSE(PBitStringAux pBitString,const int32_t kiValue)140 static inline int32_t BsWriteSE (PBitStringAux pBitString, const int32_t kiValue) {
141 uint32_t iTmpValue;
142 if (0 == kiValue) {
143 BsWriteOneBit (pBitString, 1);
144 } else if (0 < kiValue) {
145 iTmpValue = (kiValue << 1) - 1;
146 BsWriteUE (pBitString, iTmpValue);
147 } else {
148 iTmpValue = ((-kiValue) << 1);
149 BsWriteUE (pBitString, iTmpValue);
150 }
151 return 0;
152 }
153
154
155 /*
156 * Write RBSP trailing bits
157 */
BsRbspTrailingBits(PBitStringAux pBitString)158 static inline int32_t BsRbspTrailingBits (PBitStringAux pBitString) {
159 BsWriteOneBit (pBitString, 1);
160 BsFlush (pBitString);
161
162 return 0;
163 }
164
165 }
166 #endif//EXPONENTIAL_GOLOMB_ENTROPY_CODING_COMMON_H__
167