1 /*
2 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
3 * Copyright (c) 2008 Justin Ruggles
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 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
25 */
26
27 #ifndef AVCODEC_FLAC_H
28 #define AVCODEC_FLAC_H
29
33
34 #define FLAC_STREAMINFO_SIZE 34
35 #define FLAC_MAX_CHANNELS 8
36 #define FLAC_MIN_BLOCKSIZE 16
37 #define FLAC_MAX_BLOCKSIZE 65535
38 #define FLAC_MIN_FRAME_SIZE 11
39
40 enum {
45 };
46
47 enum {
56 };
57
61 };
62
63 #define FLACCOMMONINFO \
64 int samplerate; /**< sample rate */\
65 int channels; /**< number of channels */\
66 int bps; /**< bits-per-sample */\
67
68 /**
69 * Data needed from the Streaminfo header for use by the raw FLAC demuxer
70 * and/or the FLAC decoder.
71 */
72 #define FLACSTREAMINFO \
74 int max_blocksize; /**< maximum block size, in samples */\
75 int max_framesize; /**< maximum frame size, in bytes */\
76 int64_t samples; /**< total number of samples */\
77
81
85 int ch_mode;
/**< channel decorrelation mode */
88 block sizes or a fixed block size;
89 also determines the meaning of
90 frame_or_sample_num */
92
93 /**
94 * Parse the Streaminfo metadata block
95 * @param[out] avctx codec context to set basic stream parameters
96 * @param[out] s where parsed information is stored
97 * @param[in] buffer pointer to start of 34-byte streaminfo data
98 */
101
102 /**
103 * Validate the FLAC extradata.
104 * @param[in] avctx codec context containing the extradata.
105 * @param[out] format extradata format.
106 * @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data.
107 * @return 1 if valid, 0 if not valid.
108 */
112
113 /**
114 * Calculate an estimate for the maximum frame size based on verbatim mode.
115 * @param blocksize block size, in samples
116 * @param ch number of channels
117 * @param bps bits-per-sample
118 */
120
121 /**
122 * Validate and decode a frame header.
123 * @param avctx AVCodecContext to use as av_log() context
124 * @param gb GetBitContext from which to read frame header
125 * @param[out] fi frame information
126 * @param log_level_offset log level offset. can be used to silence error messages.
127 * @return non-zero on error, 0 if ok
128 */
131
133
134 /**
135 * Parse the metadata block parameters from the header.
136 * @param[in] block_header header data, at least 4 bytes
137 * @param[out] last indicator for last metadata block
138 * @param[out] type metadata block type
139 * @param[out] size metadata block size
140 */
144 int tmp = bytestream_get_byte(&block_header);
145 if (last)
146 *last = tmp & 0x80;
147 if (type)
148 *type = tmp & 0x7F;
149 if (size)
150 *size = bytestream_get_be24(&block_header);
151 }
152
153 #endif /* AVCODEC_FLAC_H */
int64_t frame_or_sample_num
frame number or sample number
int ff_flac_is_extradata_valid(AVCodecContext *avctx, enum FLACExtradataFormat *format, uint8_t **streaminfo_start)
Validate the FLAC extradata.
FLACCOMMONINFO int blocksize
block size of the frame
int ff_flac_get_max_frame_size(int blocksize, int ch, int bps)
Calculate an estimate for the maximum frame size based on verbatim mode.
void ff_flac_set_channel_layout(AVCodecContext *avctx)
bitstream reader API header.
int ff_flac_decode_frame_header(AVCodecContext *avctx, GetBitContext *gb, FLACFrameInfo *fi, int log_level_offset)
Validate and decode a frame header.
int ch_mode
channel decorrelation mode
#define FLACCOMMONINFO
bits-per-sample
#define FLACSTREAMINFO
Data needed from the Streaminfo header for use by the raw FLAC demuxer and/or the FLAC decoder...
void ff_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s, const uint8_t *buffer)
Parse the Streaminfo metadata block.
Libavcodec external API header.
main external API structure.
static const char * format
static av_always_inline void flac_parse_block_header(const uint8_t *block_header, int *last, int *type, int *size)
Parse the metadata block parameters from the header.
int is_var_size
specifies if the stream uses variable block sizes or a fixed block size; also determines the meaning ...