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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->codec->channels = AV_RL8 (packet + 9);
58  priv->pre_skip = AV_RL16(packet + 10);
59  st->codec->delay = priv->pre_skip;
60  /*orig_sample_rate = AV_RL32(packet + 12);*/
61  /*gain = AV_RL16(packet + 16);*/
62  /*channel_map = AV_RL8 (packet + 18);*/
63 
64  if (ff_alloc_extradata(st->codec, os->psize))
65  return AVERROR(ENOMEM);
66 
67  memcpy(st->codec->extradata, packet, os->psize);
68 
69  st->codec->sample_rate = 48000;
72  st->codec->sample_rate, 1000));
73  avpriv_set_pts_info(st, 64, 1, 48000);
74  priv->need_comments = 1;
75  return 1;
76  }
77 
78  if (priv->need_comments) {
79  if (os->psize < 8 || memcmp(packet, "OpusTags", 8))
80  return AVERROR_INVALIDDATA;
81  ff_vorbis_stream_comment(avf, st, packet + 8, os->psize - 8);
82  priv->need_comments--;
83  return 1;
84  }
85 
86  return 0;
87 }
88 
89 static int opus_duration(uint8_t *src, int size)
90 {
91  unsigned nb_frames = 1;
92  unsigned toc = src[0];
93  unsigned toc_config = toc >> 3;
94  unsigned toc_count = toc & 3;
95  unsigned frame_size = toc_config < 12 ? FFMAX(480, 960 * (toc_config & 3)) :
96  toc_config < 16 ? 480 << (toc_config & 1) :
97  120 << (toc_config & 3);
98  if (toc_count == 3) {
99  if (size<2)
100  return AVERROR_INVALIDDATA;
101  nb_frames = src[1] & 0x3F;
102  } else if (toc_count) {
103  nb_frames = 2;
104  }
105 
106  return frame_size * nb_frames;
107 }
108 
109 static int opus_packet(AVFormatContext *avf, int idx)
110 {
111  struct ogg *ogg = avf->priv_data;
112  struct ogg_stream *os = &ogg->streams[idx];
113  AVStream *st = avf->streams[idx];
114  struct oggopus_private *priv = os->private;
115  uint8_t *packet = os->buf + os->pstart;
116  int ret;
117 
118  if (!os->psize)
119  return AVERROR_INVALIDDATA;
120 
121  if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS)) {
122  int seg, d;
123  int duration;
124  uint8_t *last_pkt = os->buf + os->pstart;
125  uint8_t *next_pkt = last_pkt;
126 
127  duration = 0;
128  seg = os->segp;
129  d = opus_duration(last_pkt, os->psize);
130  if (d < 0) {
132  return 0;
133  }
134  duration += d;
135  last_pkt = next_pkt = next_pkt + os->psize;
136  for (; seg < os->nsegs; seg++) {
137  next_pkt += os->segments[seg];
138  if (os->segments[seg] < 255 && next_pkt != last_pkt) {
139  int d = opus_duration(last_pkt, next_pkt - last_pkt);
140  if (d > 0)
141  duration += d;
142  last_pkt = next_pkt;
143  }
144  }
145  os->lastpts =
146  os->lastdts = os->granule - duration;
147  }
148 
149  if ((ret = opus_duration(packet, os->psize)) < 0)
150  return ret;
151 
152  os->pduration = ret;
153  if (os->lastpts != AV_NOPTS_VALUE) {
154  if (st->start_time == AV_NOPTS_VALUE)
155  st->start_time = os->lastpts;
156  priv->cur_dts = os->lastdts = os->lastpts -= priv->pre_skip;
157  }
158 
159  priv->cur_dts += os->pduration;
160  if ((os->flags & OGG_FLAG_EOS)) {
161  int64_t skip = priv->cur_dts - os->granule + priv->pre_skip;
162  skip = FFMIN(skip, os->pduration);
163  if (skip > 0) {
164  os->pduration = skip < os->pduration ? os->pduration - skip : 1;
165  os->end_trimming = skip;
166  av_log(avf, AV_LOG_DEBUG,
167  "Last packet was truncated to %d due to end trimming.\n",
168  os->pduration);
169  }
170  }
171 
172  return 0;
173 }
174 
175 const struct ogg_codec ff_opus_codec = {
176  .name = "Opus",
177  .magic = "OpusHead",
178  .magicsize = 8,
179  .header = opus_header,
180  .packet = opus_packet,
181  .nb_header = 1,
182 };
#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:89
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:4083
static int opus_header(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:38
int flags
Definition: oggdec.h:76
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:109
Format I/O context.
Definition: avformat.h:1273
unsigned int psize
Definition: oggdec.h:66
uint8_t
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1617
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1341
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
static int64_t duration
Definition: ffplay.c:326
#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 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
#define FFMAX(a, b)
Definition: common.h:79
uint8_t segments[255]
Definition: oggdec.h:80
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
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:127
#define FFMIN(a, b)
Definition: common.h:81
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:842
int frame_size
Definition: mxfenc.c:1803
AVS_Value src
Definition: avisynth_c.h:482
enum AVMediaType codec_type
Definition: avcodec.h:1510
unsigned int pduration
Definition: oggdec.h:68
int nsegs
Definition: oggdec.h:79
enum AVCodecID codec_id
Definition: avcodec.h:1519
const int8_t * name
Definition: oggdec.h:34
int sample_rate
samples per second
Definition: avcodec.h:2262
const struct ogg_codec ff_opus_codec
Definition: oggparseopus.c:175
int ff_alloc_extradata(AVCodecContext *avctx, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:2924
void * private
Definition: oggdec.h:90
int64_t lastdts
Definition: oggdec.h:73
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:894
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: avcodec.h:1470
void av_codec_set_seek_preroll(AVCodecContext *avctx, int val)
Definition: oggdec.h:101
int channels
number of audio channels
Definition: avcodec.h:2263
void * priv_data
Format private data.
Definition: avformat.h:1301
int delay
Codec delay.
Definition: avcodec.h:1664
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:252
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:240