1cabdff1aSopenharmony_ci/*
2cabdff1aSopenharmony_ci * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
3cabdff1aSopenharmony_ci * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4cabdff1aSopenharmony_ci *
5cabdff1aSopenharmony_ci * This file is part of FFmpeg.
6cabdff1aSopenharmony_ci *
7cabdff1aSopenharmony_ci * FFmpeg is free software; you can redistribute it and/or
8cabdff1aSopenharmony_ci * modify it under the terms of the GNU Lesser General Public
9cabdff1aSopenharmony_ci * License as published by the Free Software Foundation; either
10cabdff1aSopenharmony_ci * version 2.1 of the License, or (at your option) any later version.
11cabdff1aSopenharmony_ci *
12cabdff1aSopenharmony_ci * FFmpeg is distributed in the hope that it will be useful,
13cabdff1aSopenharmony_ci * but WITHOUT ANY WARRANTY; without even the implied warranty of
14cabdff1aSopenharmony_ci * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15cabdff1aSopenharmony_ci * Lesser General Public License for more details.
16cabdff1aSopenharmony_ci *
17cabdff1aSopenharmony_ci * You should have received a copy of the GNU Lesser General Public
18cabdff1aSopenharmony_ci * License along with FFmpeg; if not, write to the Free Software
19cabdff1aSopenharmony_ci * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20cabdff1aSopenharmony_ci */
21cabdff1aSopenharmony_ci
22cabdff1aSopenharmony_ci/**
23cabdff1aSopenharmony_ci * @file
24cabdff1aSopenharmony_ci * Context Adaptive Binary Arithmetic Coder.
25cabdff1aSopenharmony_ci */
26cabdff1aSopenharmony_ci
27cabdff1aSopenharmony_ci#include "libavutil/error.h"
28cabdff1aSopenharmony_ci#include "libavutil/mem_internal.h"
29cabdff1aSopenharmony_ci
30cabdff1aSopenharmony_ci#include "cabac.h"
31cabdff1aSopenharmony_ci
32cabdff1aSopenharmony_ciDECLARE_ASM_ALIGNED(1, const uint8_t, ff_h264_cabac_tables)[512 + 4*2*64 + 4*64 + 63] = {
33cabdff1aSopenharmony_ci    9,8,7,7,6,6,6,6,5,5,5,5,5,5,5,5,
34cabdff1aSopenharmony_ci    4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
35cabdff1aSopenharmony_ci    3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
36cabdff1aSopenharmony_ci    3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
37cabdff1aSopenharmony_ci    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
38cabdff1aSopenharmony_ci    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
39cabdff1aSopenharmony_ci    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
40cabdff1aSopenharmony_ci    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
41cabdff1aSopenharmony_ci    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
42cabdff1aSopenharmony_ci    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
43cabdff1aSopenharmony_ci    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
44cabdff1aSopenharmony_ci    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
45cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
46cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
47cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
48cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
49cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
50cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
51cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
52cabdff1aSopenharmony_ci    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
53cabdff1aSopenharmony_ci    // LPS range
54cabdff1aSopenharmony_ci    -128,    -128,    -128,    -128,    -128,    -128,    123,     123,
55cabdff1aSopenharmony_ci    116,     116,     111,     111,     105,     105,     100,     100,
56cabdff1aSopenharmony_ci    95,      95,      90,      90,      85,      85,      81,      81,
57cabdff1aSopenharmony_ci    77,      77,      73,      73,      69,      69,      66,      66,
58cabdff1aSopenharmony_ci    62,      62,      59,      59,      56,      56,      53,      53,
59cabdff1aSopenharmony_ci    51,      51,      48,      48,      46,      46,      43,      43,
60cabdff1aSopenharmony_ci    41,      41,      39,      39,      37,      37,      35,      35,
61cabdff1aSopenharmony_ci    33,      33,      32,      32,      30,      30,      29,      29,
62cabdff1aSopenharmony_ci    27,      27,      26,      26,      24,      24,      23,      23,
63cabdff1aSopenharmony_ci    22,      22,      21,      21,      20,      20,      19,      19,
64cabdff1aSopenharmony_ci    18,      18,      17,      17,      16,      16,      15,      15,
65cabdff1aSopenharmony_ci    14,      14,      14,      14,      13,      13,      12,      12,
66cabdff1aSopenharmony_ci    12,      12,      11,      11,      11,      11,      10,      10,
67cabdff1aSopenharmony_ci    10,      10,      9,       9,       9,       9,       8,       8,
68cabdff1aSopenharmony_ci    8,       8,       7,       7,       7,       7,       7,       7,
69cabdff1aSopenharmony_ci    6,       6,       6,       6,       6,       6,       2,       2,
70cabdff1aSopenharmony_ci    -80,     -80,     -89,     -89,     -98,     -98,     -106,    -106,
71cabdff1aSopenharmony_ci    -114,    -114,    -121,    -121,    -128,    -128,    122,     122,
72cabdff1aSopenharmony_ci    116,     116,     110,     110,     104,     104,     99,      99,
73cabdff1aSopenharmony_ci    94,      94,      89,      89,      85,      85,      80,      80,
74cabdff1aSopenharmony_ci    76,      76,      72,      72,      69,      69,      65,      65,
75cabdff1aSopenharmony_ci    62,      62,      59,      59,      56,      56,      53,      53,
76cabdff1aSopenharmony_ci    50,      50,      48,      48,      45,      45,      43,      43,
77cabdff1aSopenharmony_ci    41,      41,      39,      39,      37,      37,      35,      35,
78cabdff1aSopenharmony_ci    33,      33,      31,      31,      30,      30,      28,      28,
79cabdff1aSopenharmony_ci    27,      27,      26,      26,      24,      24,      23,      23,
80cabdff1aSopenharmony_ci    22,      22,      21,      21,      20,      20,      19,      19,
81cabdff1aSopenharmony_ci    18,      18,      17,      17,      16,      16,      15,      15,
82cabdff1aSopenharmony_ci    14,      14,      14,      14,      13,      13,      12,      12,
83cabdff1aSopenharmony_ci    12,      12,      11,      11,      11,      11,      10,      10,
84cabdff1aSopenharmony_ci    9,       9,       9,       9,       9,       9,       8,       8,
85cabdff1aSopenharmony_ci    8,       8,       7,       7,       7,       7,       2,       2,
86cabdff1aSopenharmony_ci    -48,     -48,     -59,     -59,     -69,     -69,     -78,     -78,
87cabdff1aSopenharmony_ci    -87,     -87,     -96,     -96,     -104,    -104,    -112,    -112,
88cabdff1aSopenharmony_ci    -119,    -119,    -126,    -126,    123,     123,     117,     117,
89cabdff1aSopenharmony_ci    111,     111,     105,     105,     100,     100,     95,      95,
90cabdff1aSopenharmony_ci    90,      90,      86,      86,      81,      81,      77,      77,
91cabdff1aSopenharmony_ci    73,      73,      69,      69,      66,      66,      63,      63,
92cabdff1aSopenharmony_ci    59,      59,      56,      56,      54,      54,      51,      51,
93cabdff1aSopenharmony_ci    48,      48,      46,      46,      43,      43,      41,      41,
94cabdff1aSopenharmony_ci    39,      39,      37,      37,      35,      35,      33,      33,
95cabdff1aSopenharmony_ci    32,      32,      30,      30,      29,      29,      27,      27,
96cabdff1aSopenharmony_ci    26,      26,      25,      25,      23,      23,      22,      22,
97cabdff1aSopenharmony_ci    21,      21,      20,      20,      19,      19,      18,      18,
98cabdff1aSopenharmony_ci    17,      17,      16,      16,      15,      15,      15,      15,
99cabdff1aSopenharmony_ci    14,      14,      13,      13,      12,      12,      12,      12,
100cabdff1aSopenharmony_ci    11,      11,      11,      11,      10,      10,      10,      10,
101cabdff1aSopenharmony_ci    9,       9,       9,       9,       8,       8,       2,       2,
102cabdff1aSopenharmony_ci    -16,     -16,     -29,     -29,     -40,     -40,     -51,     -51,
103cabdff1aSopenharmony_ci    -61,     -61,     -71,     -71,     -81,     -81,     -90,     -90,
104cabdff1aSopenharmony_ci    -98,     -98,     -106,    -106,    -114,    -114,    -121,    -121,
105cabdff1aSopenharmony_ci    -128,    -128,    122,     122,     116,     116,     110,     110,
106cabdff1aSopenharmony_ci    104,     104,     99,      99,      94,      94,      89,      89,
107cabdff1aSopenharmony_ci    85,      85,      80,      80,      76,      76,      72,      72,
108cabdff1aSopenharmony_ci    69,      69,      65,      65,      62,      62,      59,      59,
109cabdff1aSopenharmony_ci    56,      56,      53,      53,      50,      50,      48,      48,
110cabdff1aSopenharmony_ci    45,      45,      43,      43,      41,      41,      39,      39,
111cabdff1aSopenharmony_ci    37,      37,      35,      35,      33,      33,      31,      31,
112cabdff1aSopenharmony_ci    30,      30,      28,      28,      27,      27,      25,      25,
113cabdff1aSopenharmony_ci    24,      24,      23,      23,      22,      22,      21,      21,
114cabdff1aSopenharmony_ci    20,      20,      19,      19,      18,      18,      17,      17,
115cabdff1aSopenharmony_ci    16,      16,      15,      15,      14,      14,      14,      14,
116cabdff1aSopenharmony_ci    13,      13,      12,      12,      12,      12,      11,      11,
117cabdff1aSopenharmony_ci    11,      11,      10,      10,      9,       9,       2,       2,
118cabdff1aSopenharmony_ci    // mlps state
119cabdff1aSopenharmony_ci    127,     126,     77,      76,      77,      76,      75,      74,
120cabdff1aSopenharmony_ci    75,      74,      75,      74,      73,      72,      73,      72,
121cabdff1aSopenharmony_ci    73,      72,      71,      70,      71,      70,      71,      70,
122cabdff1aSopenharmony_ci    69,      68,      69,      68,      67,      66,      67,      66,
123cabdff1aSopenharmony_ci    67,      66,      65,      64,      65,      64,      63,      62,
124cabdff1aSopenharmony_ci    61,      60,      61,      60,      61,      60,      59,      58,
125cabdff1aSopenharmony_ci    59,      58,      57,      56,      55,      54,      55,      54,
126cabdff1aSopenharmony_ci    53,      52,      53,      52,      51,      50,      49,      48,
127cabdff1aSopenharmony_ci    49,      48,      47,      46,      45,      44,      45,      44,
128cabdff1aSopenharmony_ci    43,      42,      43,      42,      39,      38,      39,      38,
129cabdff1aSopenharmony_ci    37,      36,      37,      36,      33,      32,      33,      32,
130cabdff1aSopenharmony_ci    31,      30,      31,      30,      27,      26,      27,      26,
131cabdff1aSopenharmony_ci    25,      24,      23,      22,      23,      22,      19,      18,
132cabdff1aSopenharmony_ci    19,      18,      17,      16,      15,      14,      13,      12,
133cabdff1aSopenharmony_ci    11,      10,      9,       8,       9,       8,       5,       4,
134cabdff1aSopenharmony_ci    5,       4,       3,       2,       1,       0,       0,       1,
135cabdff1aSopenharmony_ci    2,       3,       4,       5,       6,       7,       8,       9,
136cabdff1aSopenharmony_ci    10,      11,      12,      13,      14,      15,      16,      17,
137cabdff1aSopenharmony_ci    18,      19,      20,      21,      22,      23,      24,      25,
138cabdff1aSopenharmony_ci    26,      27,      28,      29,      30,      31,      32,      33,
139cabdff1aSopenharmony_ci    34,      35,      36,      37,      38,      39,      40,      41,
140cabdff1aSopenharmony_ci    42,      43,      44,      45,      46,      47,      48,      49,
141cabdff1aSopenharmony_ci    50,      51,      52,      53,      54,      55,      56,      57,
142cabdff1aSopenharmony_ci    58,      59,      60,      61,      62,      63,      64,      65,
143cabdff1aSopenharmony_ci    66,      67,      68,      69,      70,      71,      72,      73,
144cabdff1aSopenharmony_ci    74,      75,      76,      77,      78,      79,      80,      81,
145cabdff1aSopenharmony_ci    82,      83,      84,      85,      86,      87,      88,      89,
146cabdff1aSopenharmony_ci    90,      91,      92,      93,      94,      95,      96,      97,
147cabdff1aSopenharmony_ci    98,      99,      100,     101,     102,     103,     104,     105,
148cabdff1aSopenharmony_ci    106,     107,     108,     109,     110,     111,     112,     113,
149cabdff1aSopenharmony_ci    114,     115,     116,     117,     118,     119,     120,     121,
150cabdff1aSopenharmony_ci    122,     123,     124,     125,     124,     125,     126,     127,
151cabdff1aSopenharmony_ci    // last_coeff_flag_offset_8x8
152cabdff1aSopenharmony_ci    0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
153cabdff1aSopenharmony_ci    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
154cabdff1aSopenharmony_ci    3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
155cabdff1aSopenharmony_ci    5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8
156cabdff1aSopenharmony_ci};
157cabdff1aSopenharmony_ci
158cabdff1aSopenharmony_ci/**
159cabdff1aSopenharmony_ci *
160cabdff1aSopenharmony_ci * @param buf_size size of buf in bits
161cabdff1aSopenharmony_ci */
162cabdff1aSopenharmony_ciint ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size){
163cabdff1aSopenharmony_ci    c->bytestream_start=
164cabdff1aSopenharmony_ci    c->bytestream= buf;
165cabdff1aSopenharmony_ci    c->bytestream_end= buf + buf_size;
166cabdff1aSopenharmony_ci
167cabdff1aSopenharmony_ci#if CABAC_BITS == 16
168cabdff1aSopenharmony_ci    c->low =  (*c->bytestream++)<<18;
169cabdff1aSopenharmony_ci    c->low+=  (*c->bytestream++)<<10;
170cabdff1aSopenharmony_ci    // Keep our fetches on a 2-byte boundary as this should avoid ever having to
171cabdff1aSopenharmony_ci    // do unaligned loads if the compiler (or asm) optimises the double byte
172cabdff1aSopenharmony_ci    // load into a single instruction
173cabdff1aSopenharmony_ci    if(((uintptr_t)c->bytestream & 1) == 0) {
174cabdff1aSopenharmony_ci        c->low += (1 << 9);
175cabdff1aSopenharmony_ci    }
176cabdff1aSopenharmony_ci    else {
177cabdff1aSopenharmony_ci        c->low += ((*c->bytestream++) << 2) + 2;
178cabdff1aSopenharmony_ci    }
179cabdff1aSopenharmony_ci#else
180cabdff1aSopenharmony_ci    c->low =  (*c->bytestream++)<<10;
181cabdff1aSopenharmony_ci    c->low+= ((*c->bytestream++)<<2) + 2;
182cabdff1aSopenharmony_ci#endif
183cabdff1aSopenharmony_ci    c->range= 0x1FE;
184cabdff1aSopenharmony_ci    if ((c->range<<(CABAC_BITS+1)) < c->low)
185cabdff1aSopenharmony_ci        return AVERROR_INVALIDDATA;
186cabdff1aSopenharmony_ci    return 0;
187cabdff1aSopenharmony_ci}
188