2 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
3 * Copyright (c) 2008 Justin Ruggles
5 * This file is part of FFmpeg.
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.
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.
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
24 * FLAC (Free Lossless Audio Codec) decoder/demuxer common functions
27 #ifndef AVCODEC_FLAC_H
28 #define AVCODEC_FLAC_H
31 #include "bytestream.h"
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
41 FLAC_CHMODE_INDEPENDENT
= 0,
42 FLAC_CHMODE_LEFT_SIDE
= 1,
43 FLAC_CHMODE_RIGHT_SIDE
= 2,
44 FLAC_CHMODE_MID_SIDE
= 3,
48 FLAC_METADATA_TYPE_STREAMINFO
= 0,
49 FLAC_METADATA_TYPE_PADDING
,
50 FLAC_METADATA_TYPE_APPLICATION
,
51 FLAC_METADATA_TYPE_SEEKTABLE
,
52 FLAC_METADATA_TYPE_VORBIS_COMMENT
,
53 FLAC_METADATA_TYPE_CUESHEET
,
54 FLAC_METADATA_TYPE_PICTURE
,
55 FLAC_METADATA_TYPE_INVALID
= 127
58 enum FLACExtradataFormat
{
59 FLAC_EXTRADATA_FORMAT_STREAMINFO
= 0,
60 FLAC_EXTRADATA_FORMAT_FULL_HEADER
= 1
63 #define FLACCOMMONINFO \
64 int samplerate; /**< sample rate */\
65 int channels; /**< number of channels */\
66 int bps; /**< bits-per-sample */\
69 * Data needed from the Streaminfo header for use by the raw FLAC demuxer
70 * and/or the FLAC decoder.
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 */\
78 typedef struct FLACStreaminfo {
82 typedef struct FLACFrameInfo
{
84 int blocksize
; /**< block size of the frame */
85 int ch_mode
; /**< channel decorrelation mode */
86 int64_t frame_or_sample_num
; /**< frame number or sample number */
87 int is_var_size
; /**< specifies if the stream uses variable
88 block sizes or a fixed block size;
89 also determines the meaning of
90 frame_or_sample_num */
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
99 void ff_flac_parse_streaminfo(AVCodecContext
*avctx
, struct FLACStreaminfo
*s
,
100 const uint8_t *buffer
);
102 #if LIBAVCODEC_VERSION_MAJOR < 57
103 void avpriv_flac_parse_streaminfo(AVCodecContext
*avctx
, struct FLACStreaminfo
*s
,
104 const uint8_t *buffer
);
105 int avpriv_flac_is_extradata_valid(AVCodecContext
*avctx
,
106 enum FLACExtradataFormat
*format
,
107 uint8_t **streaminfo_start
);
111 * Validate the FLAC extradata.
112 * @param[in] avctx codec context containing the extradata.
113 * @param[out] format extradata format.
114 * @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data.
115 * @return 1 if valid, 0 if not valid.
117 int ff_flac_is_extradata_valid(AVCodecContext
*avctx
,
118 enum FLACExtradataFormat
*format
,
119 uint8_t **streaminfo_start
);
122 * Calculate an estimate for the maximum frame size based on verbatim mode.
123 * @param blocksize block size, in samples
124 * @param ch number of channels
125 * @param bps bits-per-sample
127 int ff_flac_get_max_frame_size(int blocksize
, int ch
, int bps
);
130 * Validate and decode a frame header.
131 * @param avctx AVCodecContext to use as av_log() context
132 * @param gb GetBitContext from which to read frame header
133 * @param[out] fi frame information
134 * @param log_level_offset log level offset. can be used to silence error messages.
135 * @return non-zero on error, 0 if ok
137 int ff_flac_decode_frame_header(AVCodecContext
*avctx
, GetBitContext
*gb
,
138 FLACFrameInfo
*fi
, int log_level_offset
);
140 void ff_flac_set_channel_layout(AVCodecContext
*avctx
);
143 * Parse the metadata block parameters from the header.
144 * @param[in] block_header header data, at least 4 bytes
145 * @param[out] last indicator for last metadata block
146 * @param[out] type metadata block type
147 * @param[out] size metadata block size
149 static av_always_inline
void flac_parse_block_header(const uint8_t *block_header
,
150 int *last
, int *type
, int *size
)
152 int tmp
= bytestream_get_byte(&block_header
);
158 *size
= bytestream_get_be24(&block_header
);
161 #endif /* AVCODEC_FLAC_H */