oggenc.c
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1 /*
2  * Ogg muxer
3  * Copyright (c) 2007 Baptiste Coudurier <baptiste dot coudurier at free dot fr>
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/crc.h"
23 #include "libavutil/mathematics.h"
24 #include "libavutil/random_seed.h"
25 #include "libavcodec/xiph.h"
26 #include "libavcodec/bytestream.h"
27 #include "libavcodec/flac.h"
28 #include "avformat.h"
29 #include "avio_internal.h"
30 #include "internal.h"
31 #include "vorbiscomment.h"
32 
33 #define MAX_PAGE_SIZE 65025
34 
35 typedef struct {
36  int64_t granule;
38  uint8_t flags;
39  uint8_t segments_count;
40  uint8_t segments[255];
41  uint8_t data[MAX_PAGE_SIZE];
42  uint16_t size;
43 } OGGPage;
44 
45 typedef struct {
46  unsigned page_counter;
47  uint8_t *header[3];
48  int header_len[3];
50  int kfgshift;
51  int64_t last_kf_pts;
52  int vrev;
53  int eos;
54  unsigned page_count;
56  unsigned serial_num;
57  int64_t last_granule;
59 
60 typedef struct OGGPageList {
62  struct OGGPageList *next;
63 } OGGPageList;
64 
65 typedef struct {
67 } OGGContext;
68 
69 static void ogg_update_checksum(AVFormatContext *s, AVIOContext *pb, int64_t crc_offset)
70 {
71  int64_t pos = avio_tell(pb);
72  uint32_t checksum = ffio_get_checksum(pb);
73  avio_seek(pb, crc_offset, SEEK_SET);
74  avio_wb32(pb, checksum);
75  avio_seek(pb, pos, SEEK_SET);
76 }
77 
78 static int ogg_write_page(AVFormatContext *s, OGGPage *page, int extra_flags)
79 {
80  OGGStreamContext *oggstream = s->streams[page->stream_index]->priv_data;
81  AVIOContext *pb;
82  int64_t crc_offset;
83  int ret, size;
84  uint8_t *buf;
85 
86  ret = avio_open_dyn_buf(&pb);
87  if (ret < 0)
88  return ret;
90  ffio_wfourcc(pb, "OggS");
91  avio_w8(pb, 0);
92  avio_w8(pb, page->flags | extra_flags);
93  avio_wl64(pb, page->granule);
94  avio_wl32(pb, oggstream->serial_num);
95  avio_wl32(pb, oggstream->page_counter++);
96  crc_offset = avio_tell(pb);
97  avio_wl32(pb, 0); // crc
98  avio_w8(pb, page->segments_count);
99  avio_write(pb, page->segments, page->segments_count);
100  avio_write(pb, page->data, page->size);
101 
102  ogg_update_checksum(s, pb, crc_offset);
103  avio_flush(pb);
104 
105  size = avio_close_dyn_buf(pb, &buf);
106  if (size < 0)
107  return size;
108 
109  avio_write(s->pb, buf, size);
110  avio_flush(s->pb);
111  av_free(buf);
112  oggstream->page_count--;
113  return 0;
114 }
115 
116 static int64_t ogg_granule_to_timestamp(OGGStreamContext *oggstream, int64_t granule)
117 {
118  if (oggstream->kfgshift)
119  return (granule>>oggstream->kfgshift) +
120  (granule & ((1<<oggstream->kfgshift)-1));
121  else
122  return granule;
123 }
124 
126 {
127  AVStream *st2 = s->streams[next->stream_index];
128  AVStream *st = s->streams[page->stream_index];
129  int64_t next_granule, cur_granule;
130 
131  if (next->granule == -1 || page->granule == -1)
132  return 0;
133 
134  next_granule = av_rescale_q(ogg_granule_to_timestamp(st2->priv_data, next->granule),
135  st2->time_base, AV_TIME_BASE_Q);
136  cur_granule = av_rescale_q(ogg_granule_to_timestamp(st->priv_data, page->granule),
137  st ->time_base, AV_TIME_BASE_Q);
138  return next_granule > cur_granule;
139 }
140 
141 static int ogg_reset_cur_page(OGGStreamContext *oggstream)
142 {
143  oggstream->page.granule = -1;
144  oggstream->page.flags = 0;
145  oggstream->page.segments_count = 0;
146  oggstream->page.size = 0;
147  return 0;
148 }
149 
151 {
152  OGGContext *ogg = s->priv_data;
153  OGGPageList **p = &ogg->page_list;
154  OGGPageList *l = av_mallocz(sizeof(*l));
155 
156  if (!l)
157  return AVERROR(ENOMEM);
158  l->page = oggstream->page;
159 
160  oggstream->page_count++;
161  ogg_reset_cur_page(oggstream);
162 
163  while (*p) {
164  if (ogg_compare_granule(s, &(*p)->page, &l->page))
165  break;
166  p = &(*p)->next;
167  }
168  l->next = *p;
169  *p = l;
170 
171  return 0;
172 }
173 
175  uint8_t *data, unsigned size, int64_t granule)
176 {
177  OGGStreamContext *oggstream = st->priv_data;
178  int total_segments = size / 255 + 1;
179  uint8_t *p = data;
180  int i, segments, len, flush = 0;
181 
182  // Handles VFR by flushing page because this frame needs to have a timestamp
183  if (st->codec->codec_id == CODEC_ID_THEORA &&
184  ogg_granule_to_timestamp(oggstream, granule) >
185  ogg_granule_to_timestamp(oggstream, oggstream->last_granule) + 1) {
186  if (oggstream->page.granule != -1)
187  ogg_buffer_page(s, oggstream);
188  flush = 1;
189  }
190 
191  for (i = 0; i < total_segments; ) {
192  OGGPage *page = &oggstream->page;
193 
194  segments = FFMIN(total_segments - i, 255 - page->segments_count);
195 
196  if (i && !page->segments_count)
197  page->flags |= 1; // continued packet
198 
199  memset(page->segments+page->segments_count, 255, segments - 1);
200  page->segments_count += segments - 1;
201 
202  len = FFMIN(size, segments*255);
203  page->segments[page->segments_count++] = len - (segments-1)*255;
204  memcpy(page->data+page->size, p, len);
205  p += len;
206  size -= len;
207  i += segments;
208  page->size += len;
209 
210  if (i == total_segments)
211  page->granule = granule;
212 
213  if (page->segments_count == 255) {
214  ogg_buffer_page(s, oggstream);
215  }
216  }
217 
218  if (flush && oggstream->page.granule != -1)
219  ogg_buffer_page(s, oggstream);
220 
221  return 0;
222 }
223 
224 static uint8_t *ogg_write_vorbiscomment(int offset, int bitexact,
225  int *header_len, AVDictionary **m, int framing_bit)
226 {
227  const char *vendor = bitexact ? "Libav" : LIBAVFORMAT_IDENT;
228  int size;
229  uint8_t *p, *p0;
230  unsigned int count;
231 
233 
234  size = offset + ff_vorbiscomment_length(*m, vendor, &count) + framing_bit;
235  p = av_mallocz(size);
236  if (!p)
237  return NULL;
238  p0 = p;
239 
240  p += offset;
241  ff_vorbiscomment_write(&p, m, vendor, count);
242  if (framing_bit)
243  bytestream_put_byte(&p, 1);
244 
245  *header_len = size;
246  return p0;
247 }
248 
250  OGGStreamContext *oggstream, int bitexact,
251  AVDictionary **m)
252 {
253  enum FLACExtradataFormat format;
254  uint8_t *streaminfo;
255  uint8_t *p;
256 
257  if (!avpriv_flac_is_extradata_valid(avctx, &format, &streaminfo))
258  return -1;
259 
260  // first packet: STREAMINFO
261  oggstream->header_len[0] = 51;
262  oggstream->header[0] = av_mallocz(51); // per ogg flac specs
263  p = oggstream->header[0];
264  if (!p)
265  return AVERROR(ENOMEM);
266  bytestream_put_byte(&p, 0x7F);
267  bytestream_put_buffer(&p, "FLAC", 4);
268  bytestream_put_byte(&p, 1); // major version
269  bytestream_put_byte(&p, 0); // minor version
270  bytestream_put_be16(&p, 1); // headers packets without this one
271  bytestream_put_buffer(&p, "fLaC", 4);
272  bytestream_put_byte(&p, 0x00); // streaminfo
273  bytestream_put_be24(&p, 34);
275 
276  // second packet: VorbisComment
277  p = ogg_write_vorbiscomment(4, bitexact, &oggstream->header_len[1], m, 0);
278  if (!p)
279  return AVERROR(ENOMEM);
280  oggstream->header[1] = p;
281  bytestream_put_byte(&p, 0x84); // last metadata block and vorbis comment
282  bytestream_put_be24(&p, oggstream->header_len[1] - 4);
283 
284  return 0;
285 }
286 
287 #define SPEEX_HEADER_SIZE 80
288 
290  OGGStreamContext *oggstream, int bitexact,
291  AVDictionary **m)
292 {
293  uint8_t *p;
294 
295  if (avctx->extradata_size < SPEEX_HEADER_SIZE)
296  return -1;
297 
298  // first packet: Speex header
300  if (!p)
301  return AVERROR(ENOMEM);
302  oggstream->header[0] = p;
303  oggstream->header_len[0] = SPEEX_HEADER_SIZE;
305  AV_WL32(&oggstream->header[0][68], 0); // set extra_headers to 0
306 
307  // second packet: VorbisComment
308  p = ogg_write_vorbiscomment(0, bitexact, &oggstream->header_len[1], m, 0);
309  if (!p)
310  return AVERROR(ENOMEM);
311  oggstream->header[1] = p;
312 
313  return 0;
314 }
315 
317 {
318  OGGStreamContext *oggstream;
319  int i, j;
320 
321  for (i = 0; i < s->nb_streams; i++) {
322  AVStream *st = s->streams[i];
323  unsigned serial_num = i;
324 
325  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
326  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
327  else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
329  if (st->codec->codec_id != CODEC_ID_VORBIS &&
330  st->codec->codec_id != CODEC_ID_THEORA &&
331  st->codec->codec_id != CODEC_ID_SPEEX &&
332  st->codec->codec_id != CODEC_ID_FLAC) {
333  av_log(s, AV_LOG_ERROR, "Unsupported codec id in stream %d\n", i);
334  return -1;
335  }
336 
337  if (!st->codec->extradata || !st->codec->extradata_size) {
338  av_log(s, AV_LOG_ERROR, "No extradata present\n");
339  return -1;
340  }
341  oggstream = av_mallocz(sizeof(*oggstream));
342  oggstream->page.stream_index = i;
343 
344  if (!(st->codec->flags & CODEC_FLAG_BITEXACT))
345  do {
346  serial_num = av_get_random_seed();
347  for (j = 0; j < i; j++) {
348  OGGStreamContext *sc = s->streams[j]->priv_data;
349  if (serial_num == sc->serial_num)
350  break;
351  }
352  } while (j < i);
353  oggstream->serial_num = serial_num;
354 
355  st->priv_data = oggstream;
356  if (st->codec->codec_id == CODEC_ID_FLAC) {
357  int err = ogg_build_flac_headers(st->codec, oggstream,
359  &s->metadata);
360  if (err) {
361  av_log(s, AV_LOG_ERROR, "Error writing FLAC headers\n");
362  av_freep(&st->priv_data);
363  return err;
364  }
365  } else if (st->codec->codec_id == CODEC_ID_SPEEX) {
366  int err = ogg_build_speex_headers(st->codec, oggstream,
368  &s->metadata);
369  if (err) {
370  av_log(s, AV_LOG_ERROR, "Error writing Speex headers\n");
371  av_freep(&st->priv_data);
372  return err;
373  }
374  } else {
375  uint8_t *p;
376  const char *cstr = st->codec->codec_id == CODEC_ID_VORBIS ? "vorbis" : "theora";
377  int header_type = st->codec->codec_id == CODEC_ID_VORBIS ? 3 : 0x81;
378  int framing_bit = st->codec->codec_id == CODEC_ID_VORBIS ? 1 : 0;
379 
381  st->codec->codec_id == CODEC_ID_VORBIS ? 30 : 42,
382  oggstream->header, oggstream->header_len) < 0) {
383  av_log(s, AV_LOG_ERROR, "Extradata corrupted\n");
384  av_freep(&st->priv_data);
385  return -1;
386  }
387 
389  &oggstream->header_len[1], &s->metadata,
390  framing_bit);
391  if (!p)
392  return AVERROR(ENOMEM);
393 
394  oggstream->header[1] = p;
395  bytestream_put_byte(&p, header_type);
396  bytestream_put_buffer(&p, cstr, 6);
397 
398  if (st->codec->codec_id == CODEC_ID_THEORA) {
401  oggstream->kfgshift = ((oggstream->header[0][40]&3)<<3)|(oggstream->header[0][41]>>5);
402  oggstream->vrev = oggstream->header[0][9];
403  av_log(s, AV_LOG_DEBUG, "theora kfgshift %d, vrev %d\n",
404  oggstream->kfgshift, oggstream->vrev);
405  }
406  }
407  }
408 
409  for (j = 0; j < s->nb_streams; j++) {
410  OGGStreamContext *oggstream = s->streams[j]->priv_data;
411  ogg_buffer_data(s, s->streams[j], oggstream->header[0],
412  oggstream->header_len[0], 0);
413  oggstream->page.flags |= 2; // bos
414  ogg_buffer_page(s, oggstream);
415  }
416  for (j = 0; j < s->nb_streams; j++) {
417  AVStream *st = s->streams[j];
418  OGGStreamContext *oggstream = st->priv_data;
419  for (i = 1; i < 3; i++) {
420  if (oggstream && oggstream->header_len[i])
421  ogg_buffer_data(s, st, oggstream->header[i],
422  oggstream->header_len[i], 0);
423  }
424  ogg_buffer_page(s, oggstream);
425  }
426  return 0;
427 }
428 
430 {
431  OGGContext *ogg = s->priv_data;
432  OGGPageList *next, *p;
433 
434  if (!ogg->page_list)
435  return;
436 
437  for (p = ogg->page_list; p; ) {
438  OGGStreamContext *oggstream =
440  if (oggstream->page_count < 2 && !flush)
441  break;
442  ogg_write_page(s, &p->page,
443  flush && oggstream->page_count == 1 ? 4 : 0); // eos
444  next = p->next;
445  av_freep(&p);
446  p = next;
447  }
448  ogg->page_list = p;
449 }
450 
452 {
453  AVStream *st = s->streams[pkt->stream_index];
454  OGGStreamContext *oggstream = st->priv_data;
455  int ret;
456  int64_t granule;
457 
458  if (st->codec->codec_id == CODEC_ID_THEORA) {
459  int64_t pts = oggstream->vrev < 1 ? pkt->pts : pkt->pts + pkt->duration;
460  int pframe_count;
461  if (pkt->flags & AV_PKT_FLAG_KEY)
462  oggstream->last_kf_pts = pts;
463  pframe_count = pts - oggstream->last_kf_pts;
464  // prevent frame count from overflow if key frame flag is not set
465  if (pframe_count >= (1<<oggstream->kfgshift)) {
466  oggstream->last_kf_pts += pframe_count;
467  pframe_count = 0;
468  }
469  granule = (oggstream->last_kf_pts<<oggstream->kfgshift) | pframe_count;
470  } else
471  granule = pkt->pts + pkt->duration;
472 
473  ret = ogg_buffer_data(s, st, pkt->data, pkt->size, granule);
474  if (ret < 0)
475  return ret;
476 
477  ogg_write_pages(s, 0);
478 
479  oggstream->last_granule = granule;
480 
481  return 0;
482 }
483 
485 {
486  int i;
487 
488  /* flush current page */
489  for (i = 0; i < s->nb_streams; i++)
490  ogg_buffer_page(s, s->streams[i]->priv_data);
491 
492  ogg_write_pages(s, 1);
493 
494  for (i = 0; i < s->nb_streams; i++) {
495  AVStream *st = s->streams[i];
496  OGGStreamContext *oggstream = st->priv_data;
497  if (st->codec->codec_id == CODEC_ID_FLAC ||
498  st->codec->codec_id == CODEC_ID_SPEEX) {
499  av_free(oggstream->header[0]);
500  av_free(oggstream->header[1]);
501  }
502  av_freep(&st->priv_data);
503  }
504  return 0;
505 }
506 
508  .name = "ogg",
509  .long_name = NULL_IF_CONFIG_SMALL("Ogg"),
510  .mime_type = "application/ogg",
511  .extensions = "ogg,ogv,spx",
512  .priv_data_size = sizeof(OGGContext),
513  .audio_codec = CODEC_ID_FLAC,
514  .video_codec = CODEC_ID_THEORA,
518 };