xref: /third_party/ffmpeg/libavcodec/ac3defs.h (revision cabdff1a) 
1/*
2 * Common AC-3 definitions
3 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
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#ifndef AVCODEC_AC3DEFS_H
23#define AVCODEC_AC3DEFS_H
24
25#define EAC3_MAX_CHANNELS 16          /**< maximum number of channels in EAC3 */
26#define AC3_MAX_CHANNELS 7            /**< maximum number of channels, including coupling channel */
27#define CPL_CH 0                      /**< coupling channel index */
28
29#define AC3_MAX_COEFS   256
30#define AC3_BLOCK_SIZE  256
31#define AC3_MAX_BLOCKS    6
32#define AC3_FRAME_SIZE (AC3_MAX_BLOCKS * 256)
33#define AC3_WINDOW_SIZE (AC3_BLOCK_SIZE * 2)
34#define AC3_CRITICAL_BANDS 50
35#define AC3_MAX_CPL_BANDS  18
36
37/* exponent encoding strategy */
38#define EXP_REUSE 0
39#define EXP_NEW   1
40
41#define EXP_D15   1
42#define EXP_D25   2
43#define EXP_D45   3
44
45/** Delta bit allocation strategy */
46typedef enum {
47    DBA_REUSE = 0,
48    DBA_NEW,
49    DBA_NONE,
50    DBA_RESERVED
51} AC3DeltaStrategy;
52
53/** Channel mode (audio coding mode) */
54typedef enum {
55    AC3_CHMODE_DUALMONO = 0,
56    AC3_CHMODE_MONO,
57    AC3_CHMODE_STEREO,
58    AC3_CHMODE_3F,
59    AC3_CHMODE_2F1R,
60    AC3_CHMODE_3F1R,
61    AC3_CHMODE_2F2R,
62    AC3_CHMODE_3F2R
63} AC3ChannelMode;
64
65/** Dolby Surround mode */
66typedef enum AC3DolbySurroundMode {
67    AC3_DSURMOD_NOTINDICATED = 0,
68    AC3_DSURMOD_OFF,
69    AC3_DSURMOD_ON,
70    AC3_DSURMOD_RESERVED
71} AC3DolbySurroundMode;
72
73/** Dolby Surround EX mode */
74typedef enum AC3DolbySurroundEXMode {
75    AC3_DSUREXMOD_NOTINDICATED = 0,
76    AC3_DSUREXMOD_OFF,
77    AC3_DSUREXMOD_ON,
78    AC3_DSUREXMOD_PLIIZ
79} AC3DolbySurroundEXMode;
80
81/** Dolby Headphone mode */
82typedef enum AC3DolbyHeadphoneMode {
83    AC3_DHEADPHONMOD_NOTINDICATED = 0,
84    AC3_DHEADPHONMOD_OFF,
85    AC3_DHEADPHONMOD_ON,
86    AC3_DHEADPHONMOD_RESERVED
87} AC3DolbyHeadphoneMode;
88
89/** Preferred Stereo Downmix mode */
90typedef enum AC3PreferredStereoDownmixMode {
91    AC3_DMIXMOD_NOTINDICATED = 0,
92    AC3_DMIXMOD_LTRT,
93    AC3_DMIXMOD_LORO,
94    AC3_DMIXMOD_DPLII // reserved value in A/52, but used by encoders to indicate DPL2
95} AC3PreferredStereoDownmixMode;
96
97typedef enum {
98    EAC3_FRAME_TYPE_INDEPENDENT = 0,
99    EAC3_FRAME_TYPE_DEPENDENT,
100    EAC3_FRAME_TYPE_AC3_CONVERT,
101    EAC3_FRAME_TYPE_RESERVED
102} EAC3FrameType;
103
104#endif /* AVCODEC_AC3DEFS_H */
105