FFmpeg
oggparseflac.c
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1 /*
2  * Copyright (C) 2005 Matthieu CASTET
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 #include <stdlib.h>
22 #include "libavcodec/avcodec.h"
23 #include "libavcodec/get_bits.h"
24 #include "libavcodec/flac.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "oggdec.h"
28 
29 #define OGG_FLAC_METADATA_TYPE_STREAMINFO 0x7F
30 
31 static int
33 {
34  struct ogg *ogg = s->priv_data;
35  struct ogg_stream *os = ogg->streams + idx;
36  AVStream *st = s->streams[idx];
37  GetBitContext gb;
38  int mdt, ret;
39 
40  if (os->buf[os->pstart] == 0xff)
41  return 0;
42 
43  init_get_bits(&gb, os->buf + os->pstart, os->psize*8);
44  skip_bits1(&gb); /* metadata_last */
45  mdt = get_bits(&gb, 7);
46 
48  uint8_t *streaminfo_start = os->buf + os->pstart + 5 + 4 + 4 + 4;
49  uint32_t samplerate;
50 
51  skip_bits_long(&gb, 4*8); /* "FLAC" */
52  if(get_bits(&gb, 8) != 1) /* unsupported major version */
53  return -1;
54  skip_bits(&gb, 8 + 16); /* minor version + header count */
55  skip_bits_long(&gb, 4*8); /* "fLaC" */
56 
57  /* METADATA_BLOCK_HEADER */
58  if (get_bits_long(&gb, 32) != FLAC_STREAMINFO_SIZE)
59  return -1;
60 
64 
66  return ret;
67  memcpy(st->codecpar->extradata, streaminfo_start, st->codecpar->extradata_size);
68 
69  samplerate = AV_RB24(st->codecpar->extradata + 10) >> 4;
70  if (!samplerate)
71  return AVERROR_INVALIDDATA;
72 
73  avpriv_set_pts_info(st, 64, 1, samplerate);
74  } else if (mdt == FLAC_METADATA_TYPE_VORBIS_COMMENT) {
75  ff_vorbis_stream_comment(s, st, os->buf + os->pstart + 4, os->psize - 4);
76  }
77 
78  return 1;
79 }
80 
81 static int
83 {
84  struct ogg *ogg = s->priv_data;
85  AVStream *st = s->streams[idx];
86  struct ogg_stream *os = ogg->streams + idx;
88  AVCodecContext *avctx;
89  int size, ret;
90  uint8_t *data;
91 
92  if (!parser)
93  return -1;
94 
97 
99  if (!avctx) {
100  ret = AVERROR(ENOMEM);
101  goto fail;
102  }
103 
105  if (ret < 0)
106  goto fail;
107 
109  av_parser_parse2(parser, avctx,
110  &data, &size, os->buf + os->pstart, os->psize,
112 
113  av_parser_close(parser);
114 
115  if (avctx->sample_rate) {
116  avpriv_set_pts_info(st, 64, 1, avctx->sample_rate);
117  avcodec_free_context(&avctx);
118  return 0;
119  }
120 
121  avcodec_free_context(&avctx);
122  return 1;
123 fail:
124  av_parser_close(parser);
125  avcodec_free_context(&avctx);
126  return ret;
127 }
128 
129 const struct ogg_codec ff_flac_codec = {
130  .magic = "\177FLAC",
131  .magicsize = 5,
132  .header = flac_header,
133  .nb_header = 2,
134 };
135 
136 const struct ogg_codec ff_old_flac_codec = {
137  .magic = "fLaC",
138  .magicsize = 4,
139  .header = old_flac_header,
140  .nb_header = 0,
141 };
skip_bits_long
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:268
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:76
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1034
get_bits_long
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:411
ff_flac_codec
const struct ogg_codec ff_flac_codec
Definition: oggparseflac.c:129
data
const char data[16]
Definition: mxf.c:146
AV_CODEC_ID_FLAC
@ AV_CODEC_ID_FLAC
Definition: codec_id.h:450
ogg_stream::buf
uint8_t * buf
Definition: oggdec.h:61
ogg
Definition: oggdec.h:101
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:493
skip_bits
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:371
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:325
old_flac_header
static int old_flac_header(AVFormatContext *s, int idx)
Definition: oggparseflac.c:82
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:771
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:413
fail
#define fail()
Definition: checkasm.h:134
GetBitContext
Definition: get_bits.h:107
av_parser_init
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:32
flac_header
static int flac_header(AVFormatContext *s, int idx)
Definition: oggparseflac.c:32
ogg_stream::pstart
unsigned int pstart
Definition: oggdec.h:64
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:153
s
#define s(width, name)
Definition: cbs_vp9.c:256
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
OGG_FLAC_METADATA_TYPE_STREAMINFO
#define OGG_FLAC_METADATA_TYPE_STREAMINFO
Definition: oggparseflac.c:29
get_bits.h
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:386
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
NULL
#define NULL
Definition: coverity.c:32
avcodec_free_context
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
Definition: options.c:168
FLAC_STREAMINFO_SIZE
#define FLAC_STREAMINFO_SIZE
Definition: flac.h:32
AVCodecParserContext::flags
int flags
Definition: avcodec.h:2845
ogg::streams
struct ogg_stream * streams
Definition: oggdec.h:102
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:80
size
int size
Definition: twinvq_data.h:10344
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
skip_bits1
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:403
PARSER_FLAG_COMPLETE_FRAMES
#define PARSER_FLAG_COMPLETE_FRAMES
Definition: avcodec.h:2846
ogg_stream
Definition: oggdec.h:60
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: codec_par.c:182
avcodec.h
AVCodecParserContext
Definition: avcodec.h:2812
FLAC_METADATA_TYPE_VORBIS_COMMENT
@ FLAC_METADATA_TYPE_VORBIS_COMMENT
Definition: flac.h:50
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
AVSTREAM_PARSE_HEADERS
@ AVSTREAM_PARSE_HEADERS
Only parse headers, do not repack.
Definition: avformat.h:689
avformat.h
oggdec.h
AVCodecContext
main external API structure.
Definition: avcodec.h:426
ff_vorbis_stream_comment
int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st, const uint8_t *buf, int size)
Parse Vorbis comments and add metadata to an AVStream.
Definition: oggparsevorbis.c:73
av_parser_parse2
int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx, uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size, int64_t pts, int64_t dts, int64_t pos)
Parse a packet.
Definition: parser.c:115
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
ogg_stream::psize
unsigned int psize
Definition: oggdec.h:65
ff_old_flac_codec
const struct ogg_codec ff_old_flac_codec
Definition: oggparseflac.c:136
ogg_codec
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:30
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ogg_codec::magic
const int8_t * magic
Definition: oggdec.h:31
flac.h
AV_RB24
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:97
av_parser_close
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:189
ff_alloc_extradata
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0.
Definition: utils.c:238