| 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 | #if CONFIG_HARDCODED_TABLES |
| 35 | #define CABAC_TABLE_CONST const |
| 36 | #else |
| 37 | #define CABAC_TABLE_CONST |
| 38 | #endif |
| 39 | extern CABAC_TABLE_CONST uint8_t ff_h264_cabac_tables[512 + 4*2*64 + 4*64 + 63]; |
| 40 | #define H264_NORM_SHIFT_OFFSET 0 |
| 41 | #define H264_LPS_RANGE_OFFSET 512 |
| 42 | #define H264_MLPS_STATE_OFFSET 1024 |
| 43 | #define H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET 1280 |
| 44 | |
| 45 | #define CABAC_BITS 16 |
| 46 | #define CABAC_MASK ((1<<CABAC_BITS)-1) |
| 47 | |
| 48 | typedef struct CABACContext{ |
| 49 | int low; |
| 50 | int range; |
| 51 | int outstanding_count; |
| 52 | const uint8_t *bytestream_start; |
| 53 | const uint8_t *bytestream; |
| 54 | const uint8_t *bytestream_end; |
| 55 | PutBitContext pb; |
| 56 | }CABACContext; |
| 57 | |
| 58 | void ff_init_cabac_encoder(CABACContext *c, uint8_t *buf, int buf_size); |
| 59 | void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size); |
| 60 | void ff_init_cabac_states(void); |
| 61 | |
| 62 | #endif /* AVCODEC_CABAC_H */ |