blob: 1bf1c620d6b30060acb7fb1679454879dd55d2a8
1 | /* |
2 | * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder |
3 | * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at> |
4 | * |
5 | * This file is part of FFmpeg. |
6 | * |
7 | * FFmpeg is free software; you can redistribute it and/or |
8 | * modify it under the terms of the GNU Lesser General Public |
9 | * License as published by the Free Software Foundation; either |
10 | * version 2.1 of the License, or (at your option) any later version. |
11 | * |
12 | * FFmpeg is distributed in the hope that it will be useful, |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
15 | * Lesser General Public License for more details. |
16 | * |
17 | * You should have received a copy of the GNU Lesser General Public |
18 | * License along with FFmpeg; if not, write to the Free Software |
19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
20 | */ |
21 | |
22 | /** |
23 | * @file |
24 | * Context Adaptive Binary Arithmetic Coder. |
25 | */ |
26 | |
27 | #ifndef AVCODEC_CABAC_H |
28 | #define AVCODEC_CABAC_H |
29 | |
30 | #include <stdint.h> |
31 | |
32 | #include "put_bits.h" |
33 | |
34 | extern const uint8_t ff_h264_cabac_tables[512 + 4*2*64 + 4*64 + 63]; |
35 | #define H264_NORM_SHIFT_OFFSET 0 |
36 | #define H264_LPS_RANGE_OFFSET 512 |
37 | #define H264_MLPS_STATE_OFFSET 1024 |
38 | #define H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET 1280 |
39 | |
40 | #define CABAC_BITS 16 |
41 | #define CABAC_MASK ((1<<CABAC_BITS)-1) |
42 | |
43 | typedef struct CABACContext{ |
44 | int low; |
45 | int range; |
46 | int outstanding_count; |
47 | const uint8_t *bytestream_start; |
48 | const uint8_t *bytestream; |
49 | const uint8_t *bytestream_end; |
50 | PutBitContext pb; |
51 | }CABACContext; |
52 | |
53 | void ff_init_cabac_encoder(CABACContext *c, uint8_t *buf, int buf_size); |
54 | int ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size); |
55 | |
56 | #endif /* AVCODEC_CABAC_H */ |
57 |