FFmpeg: libavformat/oggparseopus.c Source File

FFmpeg
oggparseopus.c
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1 /*
2  * Opus parser for Ogg
3  * Copyright (c) 2012 Nicolas George
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 #include <string.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/mem.h"
26 #include "avformat.h"
27 #include "internal.h"
28 #include "oggdec.h"
29 
30  struct oggopus_private {
31   int need_comments;
32   unsigned pre_skip;
33   int64_t cur_dts;
34 };
35 
36  #define OPUS_SEEK_PREROLL_MS 80
37  #define OPUS_HEAD_SIZE 19
38 
39  static int parse_opus_header(AVFormatContext *avf, AVStream *st, struct ogg_stream *os,
40  struct oggopus_private *priv, uint8_t *packet,
41  size_t psize)
42 {
43  int channels;
44  int ret;
45 
46  if (psize < OPUS_HEAD_SIZE || (AV_RL8(packet + 8) & 0xF0) != 0)
47  return AVERROR_INVALIDDATA;
48 
49  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
50  st->codecpar->codec_id = AV_CODEC_ID_OPUS;
51 
52  channels = AV_RL8(packet + 9);
53  if (st->codecpar->ch_layout.nb_channels &&
54  channels != st->codecpar->ch_layout.nb_channels) {
55  av_log(avf, AV_LOG_ERROR, "Channel change is not supported\n");
56  return AVERROR_PATCHWELCOME;
57  }
58 
59  st->codecpar->ch_layout.nb_channels = channels;
60 
61  priv->pre_skip = AV_RL16(packet + 10);
62  st->codecpar->initial_padding = priv->pre_skip;
63  os->start_trimming = priv->pre_skip;
64  /*orig_sample_rate = AV_RL32(packet + 12);*/
65  /*gain = AV_RL16(packet + 16);*/
66  /*channel_map = AV_RL8 (packet + 18);*/
67 
68  ret = ff_alloc_extradata(st->codecpar, os->psize);
69  if (ret < 0)
70  return ret;
71 
72  memcpy(st->codecpar->extradata, packet, os->psize);
73 
74  st->codecpar->sample_rate = 48000;
75  st->codecpar->seek_preroll = av_rescale(OPUS_SEEK_PREROLL_MS,
76  st->codecpar->sample_rate, 1000);
77  avpriv_set_pts_info(st, 64, 1, 48000);
78 
79  priv->need_comments = 1;
80 
81  return 1;
82 }
83 
84  static int opus_header(AVFormatContext *avf, int idx)
85 {
86  struct ogg *ogg = avf->priv_data;
87  struct ogg_stream *os = &ogg->streams[idx];
88  AVStream *st = avf->streams[idx];
89  struct oggopus_private *priv = os->private;
90  uint8_t *packet = os->buf + os->pstart;
91 
92  if (!priv) {
93  priv = os->private = av_mallocz(sizeof(*priv));
94  if (!priv)
95  return AVERROR(ENOMEM);
96  }
97 
98  if (os->flags & OGG_FLAG_BOS)
99  return parse_opus_header(avf, st, os, priv, packet, os->psize);
100 
101  if (priv->need_comments) {
102  if (os->psize < 8 || memcmp(packet, "OpusTags", 8))
103  return AVERROR_INVALIDDATA;
104  ff_vorbis_stream_comment(avf, st, packet + 8, os->psize - 8);
105  priv->need_comments--;
106  return 1;
107  }
108 
109  return 0;
110 }
111 
112  static int opus_duration(uint8_t *src, int size)
113 {
114  unsigned nb_frames = 1;
115  unsigned toc = src[0];
116  unsigned toc_config = toc >> 3;
117  unsigned toc_count = toc & 3;
118  unsigned frame_size = toc_config < 12 ? FFMAX(480, 960 * (toc_config & 3)) :
119  toc_config < 16 ? 480 << (toc_config & 1) :
120  120 << (toc_config & 3);
121  if (toc_count == 3) {
122  if (size<2)
123  return AVERROR_INVALIDDATA;
124  nb_frames = src[1] & 0x3F;
125  } else if (toc_count) {
126  nb_frames = 2;
127  }
128 
129  return frame_size * nb_frames;
130 }
131 
132  static int opus_packet(AVFormatContext *avf, int idx)
133 {
134  struct ogg *ogg = avf->priv_data;
135  struct ogg_stream *os = &ogg->streams[idx];
136  AVStream *st = avf->streams[idx];
137  struct oggopus_private *priv = os->private;
138  uint8_t *packet = os->buf + os->pstart;
139  int ret;
140 
141  if (!os->psize)
142  return AVERROR_INVALIDDATA;
143  if (os->granule > (1LL << 62)) {
144  av_log(avf, AV_LOG_ERROR, "Unsupported huge granule pos %"PRId64 "\n", os->granule);
145  return AVERROR_INVALIDDATA;
146  }
147 
148  if (os->psize > 8 && !memcmp(packet, "OpusHead", 8)) {
149  ret = parse_opus_header(avf, st, os, priv, packet, os->psize);
150  if (ret < 0)
151  return ret;
152 
153  return 1;
154  }
155 
156  if (os->psize > 8 && !memcmp(packet, "OpusTags", 8)) {
157  ret = ff_vorbis_update_metadata(avf, st, os->buf + os->pstart + 8,
158  os->psize - 8);
159  if (ret < 0)
160  return ret;
161 
162  priv->need_comments = 0;
163  return 1;
164  }
165 
166  if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS)) {
167  int seg, d;
168  int duration;
169  uint8_t *last_pkt = os->buf + os->pstart;
170  uint8_t *next_pkt = last_pkt;
171 
172  duration = 0;
173  seg = os->segp;
174  d = opus_duration(last_pkt, os->psize);
175  if (d < 0) {
176  os->pflags |= AV_PKT_FLAG_CORRUPT;
177  return 0;
178  }
179  duration += d;
180  last_pkt = next_pkt = next_pkt + os->psize;
181  for (; seg < os->nsegs; seg++) {
182  next_pkt += os->segments[seg];
183  if (os->segments[seg] < 255 && next_pkt != last_pkt) {
184  int d = opus_duration(last_pkt, next_pkt - last_pkt);
185  if (d > 0)
186  duration += d;
187  last_pkt = next_pkt;
188  }
189  }
190  os->lastpts =
191  os->lastdts = os->granule - duration;
192  }
193 
194  if ((ret = opus_duration(packet, os->psize)) < 0)
195  return ret;
196 
197  os->pduration = ret;
198  if (os->lastpts != AV_NOPTS_VALUE) {
199  if (st->start_time == AV_NOPTS_VALUE)
200  st->start_time = os->lastpts;
201  priv->cur_dts = os->lastdts = os->lastpts -= priv->pre_skip;
202  }
203 
204  priv->cur_dts += os->pduration;
205  if ((os->flags & OGG_FLAG_EOS)) {
206  int64_t skip = priv->cur_dts - os->granule + priv->pre_skip;
207  skip = FFMIN(skip, os->pduration);
208  if (skip > 0) {
209  os->pduration = skip < os->pduration ? os->pduration - skip : 1;
210  os->end_trimming = skip;
211  av_log(avf, AV_LOG_DEBUG,
212  "Last packet was truncated to %d due to end trimming.\n",
213  os->pduration);
214  }
215  }
216 
217  return 0;
218 }
219 
220  const struct ogg_codec ff_opus_codec = {
221  .name = "Opus",
222  .magic = "OpusHead",
223  .magicsize = 8,
224  .header = opus_header,
225  .packet = opus_packet,
226  .nb_header = 1,
227 };
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
ogg_stream::segp
int segp
Definition: oggdec.h:85
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
ogg_stream::lastpts
int64_t lastpts
Definition: oggdec.h:78
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
ff_vorbis_update_metadata
int ff_vorbis_update_metadata(AVFormatContext *s, AVStream *st, const uint8_t *buf, int size)
Parse Vorbis comments, add metadata to an AVStream.
Definition: oggparsevorbis.c:276
int64_t
long long int64_t
Definition: coverity.c:34
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1332
ogg_stream::granule
uint64_t granule
Definition: oggdec.h:76
AVCodecParameters::seek_preroll
int seek_preroll
Audio only.
Definition: codec_par.h:214
ogg_stream::start_trimming
int start_trimming
set the number of packets to drop from the start
Definition: oggdec.h:93
ogg_stream::buf
uint8_t * buf
Definition: oggdec.h:68
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
ogg_stream::nsegs
int nsegs
Definition: oggdec.h:85
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:329
ogg
Definition: oggdec.h:110
AV_RL8
#define AV_RL8(x)
Definition: intreadwrite.h:394
OPUS_SEEK_PREROLL_MS
#define OPUS_SEEK_PREROLL_MS
Definition: oggparseopus.c:36
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:777
oggopus_private::cur_dts
int64_t cur_dts
Definition: oggparseopus.c:33
ogg_stream::lastdts
int64_t lastdts
Definition: oggdec.h:79
ff_opus_codec
const struct ogg_codec ff_opus_codec
Definition: oggparseopus.c:220
ogg_stream::pstart
unsigned int pstart
Definition: oggdec.h:71
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:210
AV_PKT_FLAG_CORRUPT
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:614
duration
int64_t duration
Definition: movenc.c:65
OPUS_HEAD_SIZE
#define OPUS_HEAD_SIZE
Definition: oggparseopus.c:37
intreadwrite.h
frame_size
int frame_size
Definition: mxfenc.c:2474
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:201
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:231
channels
channels
Definition: aptx.h:31
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
oggopus_private::pre_skip
unsigned pre_skip
Definition: oggparseopus.c:32
AVFormatContext
Format I/O context.
Definition: avformat.h:1264
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:767
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
ogg_stream::flags
int flags
Definition: oggdec.h:82
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
ogg::streams
struct ogg_stream * streams
Definition: oggdec.h:111
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
ogg_stream::private
void * private
Definition: oggdec.h:99
size
int size
Definition: twinvq_data.h:10344
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:247
ogg_codec::name
const int8_t * name
Definition: oggdec.h:33
AV_CODEC_ID_OPUS
@ AV_CODEC_ID_OPUS
Definition: codec_id.h:519
parse_opus_header
static int parse_opus_header(AVFormatContext *avf, AVStream *st, struct ogg_stream *os, struct oggopus_private *priv, uint8_t *packet, size_t psize)
Definition: oggparseopus.c:39
oggopus_private::need_comments
int need_comments
Definition: oggparseopus.c:31
oggopus_private
Definition: oggparseopus.c:30
ogg_stream::pflags
unsigned int pflags
Definition: oggdec.h:73
ogg_stream
Definition: oggdec.h:67
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:256
av_rescale
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:129
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:744
avformat.h
oggdec.h
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:74
ogg_stream::segments
uint8_t segments[255]
Definition: oggdec.h:86
mem.h
OGG_FLAG_EOS
#define OGG_FLAG_EOS
Definition: oggdec.h:121
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
ogg_stream::psize
unsigned int psize
Definition: oggdec.h:72
OGG_FLAG_BOS
#define OGG_FLAG_BOS
Definition: oggdec.h:120
ogg_codec
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:30
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
opus_packet
static int opus_packet(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:132
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:793
ogg_stream::end_trimming
int end_trimming
set the number of packets to drop from the end
Definition: oggdec.h:94
opus_duration
static int opus_duration(uint8_t *src, int size)
Definition: oggparseopus.c:112
ogg_stream::pduration
unsigned int pduration
Definition: oggdec.h:74
AVCodecParameters::initial_padding
int initial_padding
Audio only.
Definition: codec_par.h:203
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1292
opus_header
static int opus_header(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:84
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:383
src
#define src
Definition: vp8dsp.c:248
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:237
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