summaryrefslogtreecommitdiff
path: root/libavcodec/flac.h
blob: 63f41c25a498ce453d822b4d401d89b85825d1a5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
/*
 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
 * Copyright (c) 2008 Justin Ruggles
 *
 * This file is part of Libav.
 *
 * Libav is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * Libav is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
 */

#ifndef AVCODEC_FLAC_H
#define AVCODEC_FLAC_H

#include "avcodec.h"
#include "get_bits.h"

#define FLAC_STREAMINFO_SIZE   34
#define FLAC_MAX_CHANNELS       8
#define FLAC_MIN_BLOCKSIZE     16
#define FLAC_MAX_BLOCKSIZE  65535
#define FLAC_MIN_FRAME_SIZE    11

enum {
    FLAC_CHMODE_INDEPENDENT = 0,
    FLAC_CHMODE_LEFT_SIDE   = 1,
    FLAC_CHMODE_RIGHT_SIDE  = 2,
    FLAC_CHMODE_MID_SIDE    = 3,
};

enum {
    FLAC_METADATA_TYPE_STREAMINFO = 0,
    FLAC_METADATA_TYPE_PADDING,
    FLAC_METADATA_TYPE_APPLICATION,
    FLAC_METADATA_TYPE_SEEKTABLE,
    FLAC_METADATA_TYPE_VORBIS_COMMENT,
    FLAC_METADATA_TYPE_CUESHEET,
    FLAC_METADATA_TYPE_PICTURE,
    FLAC_METADATA_TYPE_INVALID = 127
};

enum FLACExtradataFormat {
    FLAC_EXTRADATA_FORMAT_STREAMINFO  = 0,
    FLAC_EXTRADATA_FORMAT_FULL_HEADER = 1
};

#define FLACCOMMONINFO \
    int samplerate;         /**< sample rate                             */\
    int channels;           /**< number of channels                      */\
    int bps;                /**< bits-per-sample                         */\

/**
 * Data needed from the Streaminfo header for use by the raw FLAC demuxer
 * and/or the FLAC decoder.
 */
#define FLACSTREAMINFO \
    FLACCOMMONINFO \
    int max_blocksize;      /**< maximum block size, in samples          */\
    int max_framesize;      /**< maximum frame size, in bytes            */\
    int64_t samples;        /**< total number of samples                 */\

typedef struct FLACStreaminfo {
    FLACSTREAMINFO
} FLACStreaminfo;

typedef struct FLACFrameInfo {
    FLACCOMMONINFO
    int blocksize;          /**< block size of the frame                 */
    int ch_mode;            /**< channel decorrelation mode              */
    int64_t frame_or_sample_num;    /**< frame number or sample number   */
    int is_var_size;                /**< specifies if the stream uses variable
                                         block sizes or a fixed block size;
                                         also determines the meaning of
                                         frame_or_sample_num             */
} FLACFrameInfo;

/**
 * Parse the Streaminfo metadata block
 * @param[out] avctx   codec context to set basic stream parameters
 * @param[out] s       where parsed information is stored
 * @param[in]  buffer  pointer to start of 34-byte streaminfo data
 */
void avpriv_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s,
                                  const uint8_t *buffer);

/**
 * Validate the FLAC extradata.
 * @param[in]  avctx codec context containing the extradata.
 * @param[out] format extradata format.
 * @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data.
 * @return 1 if valid, 0 if not valid.
 */
int avpriv_flac_is_extradata_valid(AVCodecContext *avctx,
                                   enum FLACExtradataFormat *format,
                                   uint8_t **streaminfo_start);

/**
 * Parse the metadata block parameters from the header.
 * @param[in]  block_header header data, at least 4 bytes
 * @param[out] last indicator for last metadata block
 * @param[out] type metadata block type
 * @param[out] size metadata block size
 */
void avpriv_flac_parse_block_header(const uint8_t *block_header,
                                    int *last, int *type, int *size);

/**
 * Calculate an estimate for the maximum frame size based on verbatim mode.
 * @param blocksize block size, in samples
 * @param ch number of channels
 * @param bps bits-per-sample
 */
int ff_flac_get_max_frame_size(int blocksize, int ch, int bps);

/**
 * Validate and decode a frame header.
 * @param      avctx AVCodecContext to use as av_log() context
 * @param      gb    GetBitContext from which to read frame header
 * @param[out] fi    frame information
 * @param      log_level_offset  log level offset. can be used to silence error messages.
 * @return non-zero on error, 0 if ok
 */
int ff_flac_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb,
                                FLACFrameInfo *fi, int log_level_offset);

void ff_flac_set_channel_layout(AVCodecContext *avctx);

#endif /* AVCODEC_FLAC_H */