FFmpeg  4.4.4
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 "avformat.h"
26 #include "internal.h"
27 #include "oggdec.h"
28 
31  unsigned pre_skip;
32  int64_t cur_dts;
33 };
34 
35 #define OPUS_SEEK_PREROLL_MS 80
36 #define OPUS_HEAD_SIZE 19
37 
38 static int opus_header(AVFormatContext *avf, int idx)
39 {
40  struct ogg *ogg = avf->priv_data;
41  struct ogg_stream *os = &ogg->streams[idx];
42  AVStream *st = avf->streams[idx];
43  struct oggopus_private *priv = os->private;
44  uint8_t *packet = os->buf + os->pstart;
45  int ret;
46 
47  if (!priv) {
48  priv = os->private = av_mallocz(sizeof(*priv));
49  if (!priv)
50  return AVERROR(ENOMEM);
51  }
52 
53  if (os->flags & OGG_FLAG_BOS) {
54  if (os->psize < OPUS_HEAD_SIZE || (AV_RL8(packet + 8) & 0xF0) != 0)
55  return AVERROR_INVALIDDATA;
58  st->codecpar->channels = AV_RL8(packet + 9);
59 
60  priv->pre_skip = AV_RL16(packet + 10);
61  st->codecpar->initial_padding = priv->pre_skip;
62  os->start_trimming = priv->pre_skip;
63  /*orig_sample_rate = AV_RL32(packet + 12);*/
64  /*gain = AV_RL16(packet + 16);*/
65  /*channel_map = AV_RL8 (packet + 18);*/
66 
67  if ((ret = ff_alloc_extradata(st->codecpar, os->psize)) < 0)
68  return ret;
69 
70  memcpy(st->codecpar->extradata, packet, os->psize);
71 
72  st->codecpar->sample_rate = 48000;
74  st->codecpar->sample_rate, 1000);
75  avpriv_set_pts_info(st, 64, 1, 48000);
76  priv->need_comments = 1;
77  return 1;
78  }
79 
80  if (priv->need_comments) {
81  if (os->psize < 8 || memcmp(packet, "OpusTags", 8))
82  return AVERROR_INVALIDDATA;
83  ff_vorbis_stream_comment(avf, st, packet + 8, os->psize - 8);
84  priv->need_comments--;
85  return 1;
86  }
87 
88  return 0;
89 }
90 
91 static int opus_duration(uint8_t *src, int size)
92 {
93  unsigned nb_frames = 1;
94  unsigned toc = src[0];
95  unsigned toc_config = toc >> 3;
96  unsigned toc_count = toc & 3;
97  unsigned frame_size = toc_config < 12 ? FFMAX(480, 960 * (toc_config & 3)) :
98  toc_config < 16 ? 480 << (toc_config & 1) :
99  120 << (toc_config & 3);
100  if (toc_count == 3) {
101  if (size<2)
102  return AVERROR_INVALIDDATA;
103  nb_frames = src[1] & 0x3F;
104  } else if (toc_count) {
105  nb_frames = 2;
106  }
107 
108  return frame_size * nb_frames;
109 }
110 
111 static int opus_packet(AVFormatContext *avf, int idx)
112 {
113  struct ogg *ogg = avf->priv_data;
114  struct ogg_stream *os = &ogg->streams[idx];
115  AVStream *st = avf->streams[idx];
116  struct oggopus_private *priv = os->private;
117  uint8_t *packet = os->buf + os->pstart;
118  int ret;
119 
120  if (!os->psize)
121  return AVERROR_INVALIDDATA;
122  if (os->granule > (1LL << 62)) {
123  av_log(avf, AV_LOG_ERROR, "Unsupported huge granule pos %"PRId64 "\n", os->granule);
124  return AVERROR_INVALIDDATA;
125  }
126 
127  if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS)) {
128  int seg, d;
129  int duration;
130  uint8_t *last_pkt = os->buf + os->pstart;
131  uint8_t *next_pkt = last_pkt;
132 
133  duration = 0;
134  seg = os->segp;
135  d = opus_duration(last_pkt, os->psize);
136  if (d < 0) {
138  return 0;
139  }
140  duration += d;
141  last_pkt = next_pkt = next_pkt + os->psize;
142  for (; seg < os->nsegs; seg++) {
143  next_pkt += os->segments[seg];
144  if (os->segments[seg] < 255 && next_pkt != last_pkt) {
145  int d = opus_duration(last_pkt, next_pkt - last_pkt);
146  if (d > 0)
147  duration += d;
148  last_pkt = next_pkt;
149  }
150  }
151  os->lastpts =
152  os->lastdts = os->granule - duration;
153  }
154 
155  if ((ret = opus_duration(packet, os->psize)) < 0)
156  return ret;
157 
158  os->pduration = ret;
159  if (os->lastpts != AV_NOPTS_VALUE) {
160  if (st->start_time == AV_NOPTS_VALUE)
161  st->start_time = os->lastpts;
162  priv->cur_dts = os->lastdts = os->lastpts -= priv->pre_skip;
163  }
164 
165  priv->cur_dts += os->pduration;
166  if ((os->flags & OGG_FLAG_EOS)) {
167  int64_t skip = priv->cur_dts - os->granule + priv->pre_skip;
168  skip = FFMIN(skip, os->pduration);
169  if (skip > 0) {
170  os->pduration = skip < os->pduration ? os->pduration - skip : 1;
171  os->end_trimming = skip;
172  av_log(avf, AV_LOG_DEBUG,
173  "Last packet was truncated to %d due to end trimming.\n",
174  os->pduration);
175  }
176  }
177 
178  return 0;
179 }
180 
181 const struct ogg_codec ff_opus_codec = {
182  .name = "Opus",
183  .magic = "OpusHead",
184  .magicsize = 8,
185  .header = opus_header,
186  .packet = opus_packet,
187  .nb_header = 1,
188 };
uint8_t
Main libavformat public API header.
#define AV_RL16
Definition: intreadwrite.h:42
#define FFMIN(a, b)
Definition: common.h:105
#define FFMAX(a, b)
Definition: common.h:103
@ AV_CODEC_ID_OPUS
Definition: codec_id.h:484
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:411
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
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
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
#define AV_RL8(x)
Definition: intreadwrite.h:398
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:4945
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:3314
common internal API header
int frame_size
Definition: mxfenc.c:2206
int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st, const uint8_t *buf, int size)
#define OGG_FLAG_BOS
Definition: oggdec.h:112
#define OGG_FLAG_EOS
Definition: oggdec.h:113
const struct ogg_codec ff_opus_codec
Definition: oggparseopus.c:181
static int opus_packet(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:111
static int opus_duration(uint8_t *src, int size)
Definition: oggparseopus.c:91
#define OPUS_HEAD_SIZE
Definition: oggparseopus.c:36
#define OPUS_SEEK_PREROLL_MS
Definition: oggparseopus.c:35
static int opus_header(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:38
int channels
Audio only.
Definition: codec_par.h:166
int seek_preroll
Audio only.
Definition: codec_par.h:200
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
int initial_padding
Audio only.
Definition: codec_par.h:189
Format I/O context.
Definition: avformat.h:1232
void * priv_data
Format private data.
Definition: avformat.h:1260
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1300
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:912
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
const int8_t * name
Definition: oggdec.h:34
unsigned int pduration
Definition: oggdec.h:68
int end_trimming
set the number of packets to drop from the end
Definition: oggdec.h:88
unsigned int pflags
Definition: oggdec.h:67
int nsegs
Definition: oggdec.h:79
int start_trimming
set the number of packets to drop from the start
Definition: oggdec.h:87
uint8_t segments[255]
Definition: oggdec.h:80
uint64_t granule
Definition: oggdec.h:70
int64_t lastdts
Definition: oggdec.h:73
unsigned int pstart
Definition: oggdec.h:65
unsigned int psize
Definition: oggdec.h:66
void * private
Definition: oggdec.h:91
uint8_t * buf
Definition: oggdec.h:62
int64_t lastpts
Definition: oggdec.h:72
int segp
Definition: oggdec.h:79
int flags
Definition: oggdec.h:76
Definition: oggdec.h:102
struct ogg_stream * streams
Definition: oggdec.h:103
unsigned pre_skip
Definition: oggparseopus.c:31
#define av_log(a,...)
#define src
Definition: vp8dsp.c:255
int64_t duration
Definition: movenc.c:64
int size