FFmpeg  2.1.1
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_HEAD_SIZE 19
36 
37 static int opus_header(AVFormatContext *avf, int idx)
38 {
39  struct ogg *ogg = avf->priv_data;
40  struct ogg_stream *os = &ogg->streams[idx];
41  AVStream *st = avf->streams[idx];
42  struct oggopus_private *priv = os->private;
43  uint8_t *packet = os->buf + os->pstart;
44 
45  if (!priv) {
46  priv = os->private = av_mallocz(sizeof(*priv));
47  if (!priv)
48  return AVERROR(ENOMEM);
49  }
50 
51  if (os->flags & OGG_FLAG_BOS) {
52  if (os->psize < OPUS_HEAD_SIZE || (AV_RL8(packet + 8) & 0xF0) != 0)
53  return AVERROR_INVALIDDATA;
56  st->codec->channels = AV_RL8 (packet + 9);
57  priv->pre_skip = AV_RL16(packet + 10);
58  /*orig_sample_rate = AV_RL32(packet + 12);*/
59  /*gain = AV_RL16(packet + 16);*/
60  /*channel_map = AV_RL8 (packet + 18);*/
61 
62  if (ff_alloc_extradata(st->codec, os->psize))
63  return AVERROR(ENOMEM);
64 
65  memcpy(st->codec->extradata, packet, os->psize);
66 
67  st->codec->sample_rate = 48000;
68  avpriv_set_pts_info(st, 64, 1, 48000);
69  priv->need_comments = 1;
70  return 1;
71  }
72 
73  if (priv->need_comments) {
74  if (os->psize < 8 || memcmp(packet, "OpusTags", 8))
75  return AVERROR_INVALIDDATA;
76  ff_vorbis_comment(avf, &st->metadata, packet + 8, os->psize - 8);
77  priv->need_comments--;
78  return 1;
79  }
80 
81  return 0;
82 }
83 
84 static int opus_packet(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  unsigned toc, toc_config, toc_count, frame_size, nb_frames = 1;
92 
93  if (!os->psize)
94  return AVERROR_INVALIDDATA;
95 
96  toc = *packet;
97  toc_config = toc >> 3;
98  toc_count = toc & 3;
99  frame_size = toc_config < 12 ? FFMAX(480, 960 * (toc_config & 3)) :
100  toc_config < 16 ? 480 << (toc_config & 1) :
101  120 << (toc_config & 3);
102  if (toc_count == 3) {
103  if (os->psize < 2)
104  return AVERROR_INVALIDDATA;
105  nb_frames = packet[1] & 0x3F;
106  } else if (toc_count) {
107  nb_frames = 2;
108  }
109 
110  os->pduration = frame_size * nb_frames;
111  if (os->lastpts != AV_NOPTS_VALUE) {
112  if (st->start_time == AV_NOPTS_VALUE)
113  st->start_time = os->lastpts;
114  priv->cur_dts = os->lastdts = os->lastpts -= priv->pre_skip;
115  }
116 
117  priv->cur_dts += os->pduration;
118  if ((os->flags & OGG_FLAG_EOS)) {
119  int64_t skip = priv->cur_dts - os->granule + priv->pre_skip;
120  skip = FFMIN(skip, os->pduration);
121  if (skip > 0) {
122  os->pduration = skip < os->pduration ? os->pduration - skip : 1;
123  os->end_trimming = skip;
124  av_log(avf, AV_LOG_DEBUG,
125  "Last packet was truncated to %d due to end trimming.\n",
126  os->pduration);
127  }
128  }
129 
130  return 0;
131 }
132 
133 const struct ogg_codec ff_opus_codec = {
134  .name = "Opus",
135  .magic = "OpusHead",
136  .magicsize = 8,
137  .header = opus_header,
138  .packet = opus_packet,
139  .nb_header = 1,
140 };
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
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:3922
#define AV_RL16(x)
Definition: intreadwrite.h:245
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
static int opus_header(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:37
struct ogg_codec ff_opus_codec
Definition: oggparseopus.c:133
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
int flags
Definition: oggdec.h:76
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
int64_t lastpts
Definition: oggdec.h:72
static int opus_packet(AVFormatContext *avf, int idx)
Definition: oggparseopus.c:84
AVDictionary * metadata
Definition: avformat.h:735
Format I/O context.
Definition: avformat.h:968
unsigned int psize
Definition: oggdec.h:66
uint8_t
int end_trimming
set the number of packets to drop from the end
Definition: oggdec.h:87
#define AV_RL8(x)
Definition: intreadwrite.h:390
int ff_vorbis_comment(AVFormatContext *ms, AVDictionary **m, const uint8_t *buf, int size)
static const uint8_t frame_size[4]
Definition: g723_1_data.h:58
unsigned pre_skip
Definition: oggparseopus.c:31
#define OPUS_HEAD_SIZE
Definition: oggparseopus.c:35
void * priv_data
Format private data.
Definition: avformat.h:988
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: avcodec.h:4168
#define OGG_FLAG_EOS
Definition: oggdec.h:110
uint64_t granule
Definition: oggdec.h:70
unsigned int pstart
Definition: oggdec.h:65
AVStream ** streams
Definition: avformat.h:1016
struct ogg_stream * streams
Definition: oggdec.h:100
#define FFMIN(a, b)
Definition: avcodec.h:925
#define OGG_FLAG_BOS
Definition: oggdec.h:109
Stream structure.
Definition: avformat.h:667
enum AVMediaType codec_type
Definition: avcodec.h:1154
unsigned int pduration
Definition: oggdec.h:68
#define FFMAX(a, b)
Definition: avcodec.h:923
enum AVCodecID codec_id
Definition: avcodec.h:1157
const int8_t * name
Definition: oggdec.h:34
int sample_rate
samples per second
Definition: avcodec.h:1873
int ff_alloc_extradata(AVCodecContext *avctx, int size)
Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:2690
void * private
Definition: oggdec.h:88
int64_t lastdts
Definition: oggdec.h:73
uint8_t * buf
Definition: oggdec.h:62
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:713
Main libavformat public API header.
#define AVERROR_INVALIDDATA
Definition: oggdec.h:99
int channels
number of audio channels
Definition: avcodec.h:1874
#define AVERROR(e)
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avcodec.h:2278
void * av_mallocz(size_t size) av_malloc_attrib 1(1)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:241