xref: /third_party/ffmpeg/libavcodec/dolby_e.h (revision cabdff1a) 
1/*
2 * Copyright (C) 2017 foo86
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_DOLBY_E_H
22#define AVCODEC_DOLBY_E_H
23
24#include <stdint.h>
25#include "get_bits.h"
26
27#define FRAME_SAMPLES   1792
28
29#define MAX_PROG_CONF   23
30#define MAX_PROGRAMS    8
31#define MAX_CHANNELS    8
32
33/**
34 * @struct DolbyEHeaderInfo
35 * Coded Dolby E header values up to end_gain element, plus derived values.
36 */
37typedef struct DolbyEHeaderInfo {
38    /** @name Coded elements
39     * @{
40     */
41    int         prog_conf;
42    int         nb_channels;
43    int         nb_programs;
44
45    int         fr_code;
46    int         fr_code_orig;
47
48    int         ch_size[MAX_CHANNELS];
49    int         mtd_ext_size;
50    int         meter_size;
51
52    int         rev_id[MAX_CHANNELS];
53    int         begin_gain[MAX_CHANNELS];
54    int         end_gain[MAX_CHANNELS];
55    /** @} */
56
57    /** @name Derived values
58     * @{
59     */
60    int         multi_prog_warned;
61
62    int         output_channel_order;
63
64    int         sample_rate;
65    /** @} */
66} DolbyEHeaderInfo;
67
68/**
69 * @struct DBEContext
70 * Dolby E reading context used by decoder and parser.
71 */
72typedef struct DBEContext {
73    void        *avctx;
74    GetBitContext   gb;
75
76    const uint8_t *input;
77    int         input_size;
78
79    int         word_bits;
80    int         word_bytes;
81    int         key_present;
82
83    DolbyEHeaderInfo metadata;
84
85    uint8_t     buffer[1024 * 3 + AV_INPUT_BUFFER_PADDING_SIZE];
86} DBEContext;
87
88/**
89 * Use the provided key to transform the input into data (put into s->buffer)
90 * suitable for further processing and initialize s->gb to read said data.
91 */
92int ff_dolby_e_convert_input(DBEContext *s, int nb_words, int key);
93
94/**
95 * Initialize DBEContext and parse Dolby E metadata.
96 * Set word_bits/word_bytes, input, input_size, key_present
97 * and parse the header up to the end_gain element.
98 * @param[out] s DBEContext.
99 * @param[in]  buf raw input buffer.
100 * @param[in]  buf_size must be 3 bytes at least.
101 * @return Returns 0 on success, AVERROR_INVALIDDATA on error
102 */
103int ff_dolby_e_parse_header(DBEContext *s, const uint8_t *buf, int buf_size);
104
105#endif
106