FFmpeg  4.0
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/get_bits.h"
23 #include "libavcodec/flac.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "oggdec.h"
27 
28 #define OGG_FLAC_METADATA_TYPE_STREAMINFO 0x7F
29 
30 static int
32 {
33  struct ogg *ogg = s->priv_data;
34  struct ogg_stream *os = ogg->streams + idx;
35  AVStream *st = s->streams[idx];
36  GetBitContext gb;
37  int mdt;
38 
39  if (os->buf[os->pstart] == 0xff)
40  return 0;
41 
42  init_get_bits(&gb, os->buf + os->pstart, os->psize*8);
43  skip_bits1(&gb); /* metadata_last */
44  mdt = get_bits(&gb, 7);
45 
47  uint8_t *streaminfo_start = os->buf + os->pstart + 5 + 4 + 4 + 4;
48  uint32_t samplerate;
49 
50  skip_bits_long(&gb, 4*8); /* "FLAC" */
51  if(get_bits(&gb, 8) != 1) /* unsupported major version */
52  return -1;
53  skip_bits_long(&gb, 8 + 16); /* minor version + header count */
54  skip_bits_long(&gb, 4*8); /* "fLaC" */
55 
56  /* METADATA_BLOCK_HEADER */
57  if (get_bits_long(&gb, 32) != FLAC_STREAMINFO_SIZE)
58  return -1;
59 
63 
65  return AVERROR(ENOMEM);
66  memcpy(st->codecpar->extradata, streaminfo_start, st->codecpar->extradata_size);
67 
68  samplerate = AV_RB24(st->codecpar->extradata + 10) >> 4;
69  if (!samplerate)
70  return AVERROR_INVALIDDATA;
71 
72  avpriv_set_pts_info(st, 64, 1, samplerate);
73  } else if (mdt == FLAC_METADATA_TYPE_VORBIS_COMMENT) {
74  ff_vorbis_stream_comment(s, st, os->buf + os->pstart + 4, os->psize - 4);
75  }
76 
77  return 1;
78 }
79 
80 static int
82 {
83  struct ogg *ogg = s->priv_data;
84  AVStream *st = s->streams[idx];
85  struct ogg_stream *os = ogg->streams + idx;
87  AVCodecContext *avctx;
88  int size, ret;
89  uint8_t *data;
90 
91  if (!parser)
92  return -1;
93 
96 
98  if (!avctx) {
99  ret = AVERROR(ENOMEM);
100  goto fail;
101  }
102 
103  ret = avcodec_parameters_to_context(avctx, st->codecpar);
104  if (ret < 0)
105  goto fail;
106 
108  av_parser_parse2(parser, avctx,
109  &data, &size, os->buf + os->pstart, os->psize,
111 
112  av_parser_close(parser);
113 
114  if (avctx->sample_rate) {
115  avpriv_set_pts_info(st, 64, 1, avctx->sample_rate);
116  avcodec_free_context(&avctx);
117  return 0;
118  }
119 
120  avcodec_free_context(&avctx);
121  return 1;
122 fail:
123  av_parser_close(parser);
124  avcodec_free_context(&avctx);
125  return ret;
126 }
127 
128 const struct ogg_codec ff_flac_codec = {
129  .magic = "\177FLAC",
130  .magicsize = 5,
131  .header = flac_header,
132  .nb_header = 2,
133 };
134 
135 const struct ogg_codec ff_old_flac_codec = {
136  .magic = "fLaC",
137  .magicsize = 4,
138  .header = old_flac_header,
139  .nb_header = 0,
140 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define OGG_FLAC_METADATA_TYPE_STREAMINFO
Definition: oggparseflac.c:28
int size
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:269
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4811
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:212
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
#define AV_RB24
Definition: intreadwrite.h:64
Format I/O context.
Definition: avformat.h:1342
unsigned int psize
Definition: oggdec.h:66
uint8_t
static int flac_header(AVFormatContext *s, int idx)
Definition: oggparseflac.c:31
enum AVStreamParseType need_parsing
Definition: avformat.h:1091
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1410
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: utils.c:2078
const char data[16]
Definition: mxf.c:90
bitstream reader API header.
FLAC (Free Lossless Audio Codec) decoder/demuxer common functions.
#define AVERROR(e)
Definition: error.h:43
int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st, const uint8_t *buf, int size)
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
const struct ogg_codec ff_flac_codec
Definition: oggparseflac.c:128
#define fail()
Definition: checkasm.h:116
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3902
Only parse headers, do not repack.
Definition: avformat.h:794
static int old_flac_header(AVFormatContext *s, int idx)
Definition: oggparseflac.c:81
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:3271
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:156
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:205
unsigned int pstart
Definition: oggdec.h:65
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:309
struct ogg_stream * streams
Definition: oggdec.h:102
#define FLAC_STREAMINFO_SIZE
Definition: flac.h:34
Stream structure.
Definition: avformat.h:873
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:119
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:171
int sample_rate
samples per second
Definition: avcodec.h:2173
main external API structure.
Definition: avcodec.h:1518
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:346
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:433
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:354
const int8_t * magic
Definition: oggdec.h:32
uint8_t * buf
Definition: oggdec.h:62
Main libavformat public API header.
#define PARSER_FLAG_COMPLETE_FRAMES
Definition: avcodec.h:5066
Definition: oggdec.h:101
void * priv_data
Format private data.
Definition: avformat.h:1370
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3898
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
const struct ogg_codec ff_old_flac_codec
Definition: oggparseflac.c:135
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248