xref: /third_party/ffmpeg/libavcodec/mlp_parse.h (revision cabdff1a)
1/*
2 * Copyright (c) 2007 Ian Caulfield
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#ifndef AVCODEC_MLP_PARSE_H
22#define AVCODEC_MLP_PARSE_H
23
24#include <stdint.h>
25
26#include "libavutil/channel_layout.h"
27
28#include "get_bits.h"
29
30typedef struct MLPHeaderInfo
31{
32    int stream_type;                        ///< 0xBB for MLP, 0xBA for TrueHD
33    int header_size;                        ///< Size of the major sync header, in bytes
34
35    int group1_bits;                        ///< The bit depth of the first substream
36    int group2_bits;                        ///< Bit depth of the second substream (MLP only)
37
38    int group1_samplerate;                  ///< Sample rate of first substream
39    int group2_samplerate;                  ///< Sample rate of second substream (MLP only)
40
41    int channel_arrangement;
42
43    int channel_modifier_thd_stream0;       ///< Channel modifier for substream 0 of TrueHD streams ("2-channel presentation")
44    int channel_modifier_thd_stream1;       ///< Channel modifier for substream 1 of TrueHD streams ("6-channel presentation")
45    int channel_modifier_thd_stream2;       ///< Channel modifier for substream 2 of TrueHD streams ("8-channel presentation")
46
47    int channels_mlp;                       ///< Channel count for MLP streams
48    int channels_thd_stream1;               ///< Channel count for substream 1 of TrueHD streams ("6-channel presentation")
49    int channels_thd_stream2;               ///< Channel count for substream 2 of TrueHD streams ("8-channel presentation")
50    uint64_t channel_layout_mlp;            ///< Channel layout for MLP streams
51    uint64_t channel_layout_thd_stream1;    ///< Channel layout for substream 1 of TrueHD streams ("6-channel presentation")
52    uint64_t channel_layout_thd_stream2;    ///< Channel layout for substream 2 of TrueHD streams ("8-channel presentation")
53
54    int access_unit_size;                   ///< Number of samples per coded frame
55    int access_unit_size_pow2;              ///< Next power of two above number of samples per frame
56
57    int is_vbr;                             ///< Stream is VBR instead of CBR
58    int peak_bitrate;                       ///< Peak bitrate for VBR, actual bitrate (==peak) for CBR
59
60    int num_substreams;                     ///< Number of substreams within stream
61} MLPHeaderInfo;
62
63static const uint8_t thd_chancount[13] = {
64//  LR    C   LFE  LRs LRvh  LRc LRrs  Cs   Ts  LRsd  LRw  Cvh  LFE2
65     2,   1,   1,   2,   2,   2,   2,   1,   1,   2,   2,   1,   1
66};
67
68static const uint64_t thd_layout[13] = {
69    AV_CH_FRONT_LEFT|AV_CH_FRONT_RIGHT,                     // LR
70    AV_CH_FRONT_CENTER,                                     // C
71    AV_CH_LOW_FREQUENCY,                                    // LFE
72    AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT,                       // LRs
73    AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT,             // LRvh
74    AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER, // LRc
75    AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT,                       // LRrs
76    AV_CH_BACK_CENTER,                                      // Cs
77    AV_CH_TOP_CENTER,                                       // Ts
78    AV_CH_SURROUND_DIRECT_LEFT|AV_CH_SURROUND_DIRECT_RIGHT, // LRsd
79    AV_CH_WIDE_LEFT|AV_CH_WIDE_RIGHT,                       // LRw
80    AV_CH_TOP_FRONT_CENTER,                                 // Cvh
81    AV_CH_LOW_FREQUENCY_2,                                  // LFE2
82};
83
84static inline int mlp_samplerate(int in)
85{
86    if (in == 0xF)
87        return 0;
88
89    return (in & 8 ? 44100 : 48000) << (in & 7) ;
90}
91
92static inline int truehd_channels(int chanmap)
93{
94    int channels = 0, i;
95
96    for (i = 0; i < 13; i++)
97        channels += thd_chancount[i] * ((chanmap >> i) & 1);
98
99    return channels;
100}
101
102static inline uint64_t truehd_layout(int chanmap)
103{
104    int i;
105    uint64_t layout = 0;
106
107    for (i = 0; i < 13; i++)
108        layout |= thd_layout[i] * ((chanmap >> i) & 1);
109
110    return layout;
111}
112
113int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb);
114
115#endif /* AVCODEC_MLP_PARSE_H */
116