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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 
46  if (!priv) {
47  priv = os->private = av_mallocz(sizeof(*priv));
48  if (!priv)
49  return AVERROR(ENOMEM);
50  }
51 
52  if (os->flags & OGG_FLAG_BOS) {
53  if (os->psize < OPUS_HEAD_SIZE || (AV_RL8(packet + 8) & 0xF0) != 0)
54  return AVERROR_INVALIDDATA;
57  st->codecpar->channels = AV_RL8(packet + 9);
58 
59  priv->pre_skip = AV_RL16(packet + 10);
60  st->codecpar->initial_padding = priv->pre_skip;
61  /*orig_sample_rate = AV_RL32(packet + 12);*/
62  /*gain = AV_RL16(packet + 16);*/
63  /*channel_map = AV_RL8 (packet + 18);*/
64 
66  if (ff_alloc_extradata(st->codecpar, os->psize))
67  return AVERROR(ENOMEM);
68 
69  memcpy(st->codecpar->extradata, packet, os->psize);
70 
71  st->codecpar->sample_rate = 48000;
73  st->codecpar->sample_rate, 1000);
74  avpriv_set_pts_info(st, 64, 1, 48000);
75  priv->need_comments = 1;
76  return 1;
77  }
78 
79  if (priv->need_comments) {
80  if (os->psize < 8 || memcmp(packet, "OpusTags", 8))
81  return AVERROR_INVALIDDATA;
82  ff_vorbis_stream_comment(avf, st, packet + 8, os->psize - 8);
83  priv->need_comments--;
84  return 1;
85  }
86 
87  return 0;
88 }
89 
90 static int opus_duration(uint8_t *src, int size)
91 {
92  unsigned nb_frames = 1;
93  unsigned toc = src[0];
94  unsigned toc_config = toc >> 3;
95  unsigned toc_count = toc & 3;
96  unsigned frame_size = toc_config < 12 ? FFMAX(480, 960 * (toc_config & 3)) :
97  toc_config < 16 ? 480 << (toc_config & 1) :
98  120 << (toc_config & 3);
99  if (toc_count == 3) {
100  if (size<2)
101  return AVERROR_INVALIDDATA;
102  nb_frames = src[1] & 0x3F;
103  } else if (toc_count) {
104  nb_frames = 2;
105  }
106 
107  return frame_size * nb_frames;
108 }
109 
110 static int opus_packet(AVFormatContext *avf, int idx)
111 {
112  struct ogg *ogg = avf->priv_data;
113  struct ogg_stream *os = &ogg->streams[idx];
114  AVStream *st = avf->streams[idx];
115  struct oggopus_private *priv = os->private;
116  uint8_t *packet = os->buf + os->pstart;
117  int ret;
118 
119  if (!os->psize)
120  return AVERROR_INVALIDDATA;
121  if (os->granule > (1LL << 62)) {
122  av_log(avf, AV_LOG_ERROR, "Unsupported huge granule pos %"PRId64 "\n", os->granule);
123  return AVERROR_INVALIDDATA;
124  }
125 
126  if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS)) {
127  int seg, d;
128  int duration;
129  uint8_t *last_pkt = os->buf + os->pstart;
130  uint8_t *next_pkt = last_pkt;
131 
132  duration = 0;
133  seg = os->segp;
134  d = opus_duration(last_pkt, os->psize);
135  if (d < 0) {
137  return 0;
138  }
139  duration += d;
140  last_pkt = next_pkt = next_pkt + os->psize;
141  for (; seg < os->nsegs; seg++) {
142  next_pkt += os->segments[seg];
143  if (os->segments[seg] < 255 && next_pkt != last_pkt) {
144  int d = opus_duration(last_pkt, next_pkt - last_pkt);
145  if (d > 0)
146  duration += d;
147  last_pkt = next_pkt;
148  }
149  }
150  os->lastpts =
151  os->lastdts = os->granule - duration;
152  }
153 
154  if ((ret = opus_duration(packet, os->psize)) < 0)
155  return ret;
156 
157  os->pduration = ret;
158  if (os->lastpts != AV_NOPTS_VALUE) {
159  if (st->start_time == AV_NOPTS_VALUE)
160  st->start_time = os->lastpts;
161  priv->cur_dts = os->lastdts = os->lastpts -= priv->pre_skip;
162  }
163 
164  priv->cur_dts += os->pduration;
165  if ((os->flags & OGG_FLAG_EOS)) {
166  int64_t skip = priv->cur_dts - os->granule + priv->pre_skip;
167  skip = FFMIN(skip, os->pduration);
168  if (skip > 0) {
169  os->pduration = skip < os->pduration ? os->pduration - skip : 1;
170  os->end_trimming = skip;
171  av_log(avf, AV_LOG_DEBUG,
172  "Last packet was truncated to %d due to end trimming.\n",
173  os->pduration);
174  }
175  }
176 
177  return 0;
178 }
179 
180 const struct ogg_codec ff_opus_codec = {
181  .name = "Opus",
182  .magic = "OpusHead",
183  .magicsize = 8,
184  .header = opus_header,
185  .packet = opus_packet,
186  .nb_header = 1,
187 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
#define OPUS_SEEK_PREROLL_MS
Definition: oggparseopus.c:35
unsigned int pflags
Definition: oggdec.h:67
static int opus_duration(uint8_t *src, int size)
Definition: oggparseopus.c:90
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:4820
static int opus_header(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:38
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
int flags
Definition: oggdec.h:76
#define src
Definition: vp8dsp.c:254
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
int64_t lastpts
Definition: oggdec.h:72
static int opus_packet(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:110
Format I/O context.
Definition: avformat.h:1342
unsigned int psize
Definition: oggdec.h:66
uint8_t
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1410
int64_t duration
Definition: movenc.c:63
int initial_padding
Audio only.
Definition: avcodec.h:4013
int end_trimming
set the number of packets to drop from the end
Definition: oggdec.h:87
ptrdiff_t size
Definition: opengl_enc.c:101
#define av_log(a,...)
#define AV_RL8(x)
Definition: intreadwrite.h:398
unsigned pre_skip
Definition: oggparseopus.c:31
#define OPUS_HEAD_SIZE
Definition: oggparseopus.c:36
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
int ff_vorbis_stream_comment(AVFormatContext *as, AVStream *st, const uint8_t *buf, int size)
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
#define OGG_FLAG_EOS
Definition: oggdec.h:112
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
#define FFMAX(a, b)
Definition: common.h:94
uint8_t segments[255]
Definition: oggdec.h:80
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:3280
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
#define FFMIN(a, b)
Definition: common.h:96
uint64_t granule
Definition: oggdec.h:70
unsigned int pstart
Definition: oggdec.h:65
struct ogg_stream * streams
Definition: oggdec.h:102
int segp
Definition: oggdec.h:79
#define OGG_FLAG_BOS
Definition: oggdec.h:111
Stream structure.
Definition: avformat.h:873
int frame_size
Definition: mxfenc.c:1947
unsigned int pduration
Definition: oggdec.h:68
int nsegs
Definition: oggdec.h:79
const int8_t * name
Definition: oggdec.h:34
const struct ogg_codec ff_opus_codec
Definition: oggparseopus.c:180
void * private
Definition: oggdec.h:90
int64_t lastdts
Definition: oggdec.h:73
int seek_preroll
Audio only.
Definition: avcodec.h:4024
int sample_rate
Audio only.
Definition: avcodec.h:3994
uint8_t * buf
Definition: oggdec.h:62
Main libavformat public API header.
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:912
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: avcodec.h:1463
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
int channels
Audio only.
Definition: avcodec.h:3990
#define av_freep(p)
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248