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cabac_tablegen.h
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1 /*
2  * Header file for hardcoded CABAC table
3  *
4  * Copyright (c) 2014 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef AVCODEC_CABAC_TABLEGEN_H
24 #define AVCODEC_CABAC_TABLEGEN_H
25 
26 #if CONFIG_HARDCODED_TABLES
27 #define cabac_tableinit()
28 #include "libavcodec/cabac_tables.h"
29 #else
30 uint8_t ff_h264_cabac_tables[512 + 4*2*64 + 4*64 + 63];
31 
32 static const uint8_t lps_range[64][4]= {
33 {128,176,208,240}, {128,167,197,227}, {128,158,187,216}, {123,150,178,205},
34 {116,142,169,195}, {111,135,160,185}, {105,128,152,175}, {100,122,144,166},
35 { 95,116,137,158}, { 90,110,130,150}, { 85,104,123,142}, { 81, 99,117,135},
36 { 77, 94,111,128}, { 73, 89,105,122}, { 69, 85,100,116}, { 66, 80, 95,110},
37 { 62, 76, 90,104}, { 59, 72, 86, 99}, { 56, 69, 81, 94}, { 53, 65, 77, 89},
38 { 51, 62, 73, 85}, { 48, 59, 69, 80}, { 46, 56, 66, 76}, { 43, 53, 63, 72},
39 { 41, 50, 59, 69}, { 39, 48, 56, 65}, { 37, 45, 54, 62}, { 35, 43, 51, 59},
40 { 33, 41, 48, 56}, { 32, 39, 46, 53}, { 30, 37, 43, 50}, { 29, 35, 41, 48},
41 { 27, 33, 39, 45}, { 26, 31, 37, 43}, { 24, 30, 35, 41}, { 23, 28, 33, 39},
42 { 22, 27, 32, 37}, { 21, 26, 30, 35}, { 20, 24, 29, 33}, { 19, 23, 27, 31},
43 { 18, 22, 26, 30}, { 17, 21, 25, 28}, { 16, 20, 23, 27}, { 15, 19, 22, 25},
44 { 14, 18, 21, 24}, { 14, 17, 20, 23}, { 13, 16, 19, 22}, { 12, 15, 18, 21},
45 { 12, 14, 17, 20}, { 11, 14, 16, 19}, { 11, 13, 15, 18}, { 10, 12, 15, 17},
46 { 10, 12, 14, 16}, { 9, 11, 13, 15}, { 9, 11, 12, 14}, { 8, 10, 12, 14},
47 { 8, 9, 11, 13}, { 7, 9, 11, 12}, { 7, 9, 10, 12}, { 7, 8, 10, 11},
48 { 6, 8, 9, 11}, { 6, 7, 9, 10}, { 6, 7, 8, 9}, { 2, 2, 2, 2},
49 };
50 
51 static const uint8_t mps_state[64]= {
52  1, 2, 3, 4, 5, 6, 7, 8,
53  9,10,11,12,13,14,15,16,
54  17,18,19,20,21,22,23,24,
55  25,26,27,28,29,30,31,32,
56  33,34,35,36,37,38,39,40,
57  41,42,43,44,45,46,47,48,
58  49,50,51,52,53,54,55,56,
59  57,58,59,60,61,62,62,63,
60 };
61 
62 static const uint8_t lps_state[64]= {
63  0, 0, 1, 2, 2, 4, 4, 5,
64  6, 7, 8, 9, 9,11,11,12,
65  13,13,15,15,16,16,18,18,
66  19,19,21,21,22,22,23,24,
67  24,25,26,26,27,27,28,29,
68  29,30,30,30,31,32,32,33,
69  33,33,34,34,35,35,35,36,
70  36,36,37,37,37,38,38,63,
71 };
72 
73 static const uint8_t last_coeff_flag_offset_8x8[63] = {
74  0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
75  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
76  3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
77  5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8
78 };
79 
80 static av_cold void cabac_tableinit(void)
81 {
82  int i, j;
83  for (i = 0; i < 512; i++)
84  ff_h264_norm_shift[i] = i ? 8 - av_log2(i) : 9;
85 
86  for(i=0; i<64; i++){
87  for(j=0; j<4; j++){ //FIXME check if this is worth the 1 shift we save
88  ff_h264_lps_range[j*2*64+2*i+0]=
89  ff_h264_lps_range[j*2*64+2*i+1]= lps_range[i][j];
90  }
91  ff_h264_mlps_state[128 + 2 * i + 0] = 2 * mps_state[i] + 0;
92  ff_h264_mlps_state[128 + 2 * i + 1] = 2 * mps_state[i] + 1;
93 
94  if( i ){
95  ff_h264_mlps_state[128-2*i-1]= 2*lps_state[i]+0;
96  ff_h264_mlps_state[128-2*i-2]= 2*lps_state[i]+1;
97  }else{
98  ff_h264_mlps_state[128-2*i-1]= 1;
99  ff_h264_mlps_state[128-2*i-2]= 0;
100  }
101  }
102  for(i=0; i< 63; i++){
104  }
105 }
106 #endif /* CONFIG_HARDCODED_TABLES */
107 
108 #endif /* AVCODEC_CABAC_TABLEGEN_H */