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tee.c
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1 /*
2  * Tee pseudo-muxer
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 License
9  * 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
15  * GNU Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public License
18  * along with FFmpeg; if not, write to the Free Software * Foundation, Inc.,
19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 
23 #include "libavutil/avutil.h"
24 #include "libavutil/avstring.h"
25 #include "libavutil/opt.h"
26 #include "avformat.h"
27 
28 #define MAX_SLAVES 16
29 
30 typedef struct {
32  AVBitStreamFilterContext **bsfs; ///< bitstream filters per stream
33 
34  /** map from input to output streams indexes,
35  * disabled output streams are set to -1 */
36  int *stream_map;
37 } TeeSlave;
38 
39 typedef struct TeeContext {
40  const AVClass *class;
41  unsigned nb_slaves;
43 } TeeContext;
44 
45 static const char *const slave_delim = "|";
46 static const char *const slave_opt_open = "[";
47 static const char *const slave_opt_close = "]";
48 static const char *const slave_opt_delim = ":]"; /* must have the close too */
49 static const char *const slave_bsfs_spec_sep = "/";
50 
51 static const AVClass tee_muxer_class = {
52  .class_name = "Tee muxer",
53  .item_name = av_default_item_name,
54  .version = LIBAVUTIL_VERSION_INT,
55 };
56 
57 static int parse_slave_options(void *log, char *slave,
58  AVDictionary **options, char **filename)
59 {
60  const char *p;
61  char *key, *val;
62  int ret;
63 
64  if (!strspn(slave, slave_opt_open)) {
65  *filename = slave;
66  return 0;
67  }
68  p = slave + 1;
69  if (strspn(p, slave_opt_close)) {
70  *filename = (char *)p + 1;
71  return 0;
72  }
73  while (1) {
74  ret = av_opt_get_key_value(&p, "=", slave_opt_delim, 0, &key, &val);
75  if (ret < 0) {
76  av_log(log, AV_LOG_ERROR, "No option found near \"%s\"\n", p);
77  goto fail;
78  }
79  ret = av_dict_set(options, key, val,
81  if (ret < 0)
82  goto fail;
83  if (strspn(p, slave_opt_close))
84  break;
85  p++;
86  }
87  *filename = (char *)p + 1;
88  return 0;
89 
90 fail:
91  av_dict_free(options);
92  return ret;
93 }
94 
95 /**
96  * Parse list of bitstream filters and add them to the list of filters
97  * pointed to by bsfs.
98  *
99  * The list must be specified in the form:
100  * BSFS ::= BSF[,BSFS]
101  */
102 static int parse_bsfs(void *log_ctx, const char *bsfs_spec,
104 {
105  char *bsf_name, *buf, *dup, *saveptr;
106  int ret = 0;
107 
108  if (!(dup = buf = av_strdup(bsfs_spec)))
109  return AVERROR(ENOMEM);
110 
111  while (bsf_name = av_strtok(buf, ",", &saveptr)) {
113 
114  if (!bsf) {
115  av_log(log_ctx, AV_LOG_ERROR,
116  "Cannot initialize bitstream filter with name '%s', "
117  "unknown filter or internal error happened\n",
118  bsf_name);
119  ret = AVERROR_UNKNOWN;
120  goto end;
121  }
122 
123  /* append bsf context to the list of bsf contexts */
124  *bsfs = bsf;
125  bsfs = &bsf->next;
126 
127  buf = NULL;
128  }
129 
130 end:
131  av_free(dup);
132  return ret;
133 }
134 
135 static int open_slave(AVFormatContext *avf, char *slave, TeeSlave *tee_slave)
136 {
137  int i, ret;
138  AVDictionary *options = NULL;
139  AVDictionaryEntry *entry;
140  char *filename;
141  char *format = NULL, *select = NULL;
142  AVFormatContext *avf2 = NULL;
143  AVStream *st, *st2;
144  int stream_count;
145 
146  if ((ret = parse_slave_options(avf, slave, &options, &filename)) < 0)
147  return ret;
148 
149 #define STEAL_OPTION(option, field) do { \
150  if ((entry = av_dict_get(options, option, NULL, 0))) { \
151  field = entry->value; \
152  entry->value = NULL; /* prevent it from being freed */ \
153  av_dict_set(&options, option, NULL, 0); \
154  } \
155  } while (0)
156 
157  STEAL_OPTION("f", format);
158  STEAL_OPTION("select", select);
159 
160  ret = avformat_alloc_output_context2(&avf2, NULL, format, filename);
161  if (ret < 0)
162  goto end;
163  av_dict_copy(&avf2->metadata, avf->metadata, 0);
164 
165  tee_slave->stream_map = av_calloc(avf->nb_streams, sizeof(*tee_slave->stream_map));
166  if (!tee_slave->stream_map) {
167  ret = AVERROR(ENOMEM);
168  goto end;
169  }
170 
171  stream_count = 0;
172  for (i = 0; i < avf->nb_streams; i++) {
173  st = avf->streams[i];
174  if (select) {
175  ret = avformat_match_stream_specifier(avf, avf->streams[i], select);
176  if (ret < 0) {
177  av_log(avf, AV_LOG_ERROR,
178  "Invalid stream specifier '%s' for output '%s'\n",
179  select, slave);
180  goto end;
181  }
182 
183  if (ret == 0) { /* no match */
184  tee_slave->stream_map[i] = -1;
185  continue;
186  }
187  }
188  tee_slave->stream_map[i] = stream_count++;
189 
190  if (!(st2 = avformat_new_stream(avf2, NULL))) {
191  ret = AVERROR(ENOMEM);
192  goto end;
193  }
194  st2->id = st->id;
195  st2->r_frame_rate = st->r_frame_rate;
196  st2->time_base = st->time_base;
197  st2->start_time = st->start_time;
198  st2->duration = st->duration;
199  st2->nb_frames = st->nb_frames;
200  st2->disposition = st->disposition;
202  st2->avg_frame_rate = st->avg_frame_rate;
203  av_dict_copy(&st2->metadata, st->metadata, 0);
204  if ((ret = avcodec_copy_context(st2->codec, st->codec)) < 0)
205  goto end;
206  }
207 
208  if (!(avf2->oformat->flags & AVFMT_NOFILE)) {
209  if ((ret = avio_open(&avf2->pb, filename, AVIO_FLAG_WRITE)) < 0) {
210  av_log(avf, AV_LOG_ERROR, "Slave '%s': error opening: %s\n",
211  slave, av_err2str(ret));
212  goto end;
213  }
214  }
215 
216  if ((ret = avformat_write_header(avf2, &options)) < 0) {
217  av_log(avf, AV_LOG_ERROR, "Slave '%s': error writing header: %s\n",
218  slave, av_err2str(ret));
219  goto end;
220  }
221 
222  tee_slave->avf = avf2;
223  tee_slave->bsfs = av_calloc(avf2->nb_streams, sizeof(TeeSlave));
224  if (!tee_slave->bsfs) {
225  ret = AVERROR(ENOMEM);
226  goto end;
227  }
228 
229  entry = NULL;
230  while (entry = av_dict_get(options, "bsfs", NULL, AV_DICT_IGNORE_SUFFIX)) {
231  const char *spec = entry->key + strlen("bsfs");
232  if (*spec) {
233  if (strspn(spec, slave_bsfs_spec_sep) != 1) {
234  av_log(avf, AV_LOG_ERROR,
235  "Specifier separator in '%s' is '%c', but only characters '%s' "
236  "are allowed\n", entry->key, *spec, slave_bsfs_spec_sep);
237  return AVERROR(EINVAL);
238  }
239  spec++; /* consume separator */
240  }
241 
242  for (i = 0; i < avf2->nb_streams; i++) {
243  ret = avformat_match_stream_specifier(avf2, avf2->streams[i], spec);
244  if (ret < 0) {
245  av_log(avf, AV_LOG_ERROR,
246  "Invalid stream specifier '%s' in bsfs option '%s' for slave "
247  "output '%s'\n", spec, entry->key, filename);
248  goto end;
249  }
250 
251  if (ret > 0) {
252  av_log(avf, AV_LOG_DEBUG, "spec:%s bsfs:%s matches stream %d of slave "
253  "output '%s'\n", spec, entry->value, i, filename);
254  if (tee_slave->bsfs[i]) {
255  av_log(avf, AV_LOG_WARNING,
256  "Duplicate bsfs specification associated to stream %d of slave "
257  "output '%s', filters will be ignored\n", i, filename);
258  continue;
259  }
260  ret = parse_bsfs(avf, entry->value, &tee_slave->bsfs[i]);
261  if (ret < 0) {
262  av_log(avf, AV_LOG_ERROR,
263  "Error parsing bitstream filter sequence '%s' associated to "
264  "stream %d of slave output '%s'\n", entry->value, i, filename);
265  goto end;
266  }
267  }
268  }
269 
270  av_dict_set(&options, entry->key, NULL, 0);
271  }
272 
273  if (options) {
274  entry = NULL;
275  while ((entry = av_dict_get(options, "", entry, AV_DICT_IGNORE_SUFFIX)))
276  av_log(avf2, AV_LOG_ERROR, "Unknown option '%s'\n", entry->key);
278  goto end;
279  }
280 
281 end:
282  av_free(format);
283  av_free(select);
284  av_dict_free(&options);
285  return ret;
286 }
287 
288 static void close_slaves(AVFormatContext *avf)
289 {
290  TeeContext *tee = avf->priv_data;
291  AVFormatContext *avf2;
292  unsigned i, j;
293 
294  for (i = 0; i < tee->nb_slaves; i++) {
295  avf2 = tee->slaves[i].avf;
296 
297  for (j = 0; j < avf2->nb_streams; j++) {
298  AVBitStreamFilterContext *bsf_next, *bsf = tee->slaves[i].bsfs[j];
299  while (bsf) {
300  bsf_next = bsf->next;
302  bsf = bsf_next;
303  }
304  }
305  av_freep(&tee->slaves[i].stream_map);
306  av_freep(&tee->slaves[i].bsfs);
307 
308  avio_close(avf2->pb);
309  avf2->pb = NULL;
310  avformat_free_context(avf2);
311  tee->slaves[i].avf = NULL;
312  }
313 }
314 
315 static void log_slave(TeeSlave *slave, void *log_ctx, int log_level)
316 {
317  int i;
318  av_log(log_ctx, log_level, "filename:'%s' format:%s\n",
319  slave->avf->filename, slave->avf->oformat->name);
320  for (i = 0; i < slave->avf->nb_streams; i++) {
321  AVStream *st = slave->avf->streams[i];
322  AVBitStreamFilterContext *bsf = slave->bsfs[i];
323 
324  av_log(log_ctx, log_level, " stream:%d codec:%s type:%s",
327  if (bsf) {
328  av_log(log_ctx, log_level, " bsfs:");
329  while (bsf) {
330  av_log(log_ctx, log_level, "%s%s",
331  bsf->filter->name, bsf->next ? "," : "");
332  bsf = bsf->next;
333  }
334  }
335  av_log(log_ctx, log_level, "\n");
336  }
337 }
338 
340 {
341  TeeContext *tee = avf->priv_data;
342  unsigned nb_slaves = 0, i;
343  const char *filename = avf->filename;
344  char *slaves[MAX_SLAVES];
345  int ret;
346 
347  while (*filename) {
348  if (nb_slaves == MAX_SLAVES) {
349  av_log(avf, AV_LOG_ERROR, "Maximum %d slave muxers reached.\n",
350  MAX_SLAVES);
351  ret = AVERROR_PATCHWELCOME;
352  goto fail;
353  }
354  if (!(slaves[nb_slaves++] = av_get_token(&filename, slave_delim))) {
355  ret = AVERROR(ENOMEM);
356  goto fail;
357  }
358  if (strspn(filename, slave_delim))
359  filename++;
360  }
361 
362  for (i = 0; i < nb_slaves; i++) {
363  if ((ret = open_slave(avf, slaves[i], &tee->slaves[i])) < 0)
364  goto fail;
365  log_slave(&tee->slaves[i], avf, AV_LOG_VERBOSE);
366  av_freep(&slaves[i]);
367  }
368 
369  tee->nb_slaves = nb_slaves;
370 
371  for (i = 0; i < avf->nb_streams; i++) {
372  int j, mapped = 0;
373  for (j = 0; j < tee->nb_slaves; j++)
374  mapped += tee->slaves[j].stream_map[i] >= 0;
375  if (!mapped)
376  av_log(avf, AV_LOG_WARNING, "Input stream #%d is not mapped "
377  "to any slave.\n", i);
378  }
379  return 0;
380 
381 fail:
382  for (i = 0; i < nb_slaves; i++)
383  av_freep(&slaves[i]);
384  close_slaves(avf);
385  return ret;
386 }
387 
388 static int filter_packet(void *log_ctx, AVPacket *pkt,
390 {
391  AVCodecContext *enc_ctx = fmt_ctx->streams[pkt->stream_index]->codec;
392  int ret = 0;
393 
394  while (bsf_ctx) {
395  AVPacket new_pkt = *pkt;
396  ret = av_bitstream_filter_filter(bsf_ctx, enc_ctx, NULL,
397  &new_pkt.data, &new_pkt.size,
398  pkt->data, pkt->size,
399  pkt->flags & AV_PKT_FLAG_KEY);
400  if (ret == 0 && new_pkt.data != pkt->data && new_pkt.destruct) {
401  if ((ret = av_copy_packet(&new_pkt, pkt)) < 0)
402  break;
403  ret = 1;
404  }
405 
406  if (ret > 0) {
407  av_free_packet(pkt);
408  new_pkt.buf = av_buffer_create(new_pkt.data, new_pkt.size,
409  av_buffer_default_free, NULL, 0);
410  if (!new_pkt.buf)
411  break;
412  }
413  if (ret < 0) {
414  av_log(log_ctx, AV_LOG_ERROR,
415  "Failed to filter bitstream with filter %s for stream %d in file '%s' with codec %s\n",
416  bsf_ctx->filter->name, pkt->stream_index, fmt_ctx->filename,
417  avcodec_get_name(enc_ctx->codec_id));
418  }
419  *pkt = new_pkt;
420 
421  bsf_ctx = bsf_ctx->next;
422  }
423 
424  return ret;
425 }
426 
428 {
429  TeeContext *tee = avf->priv_data;
430  AVFormatContext *avf2;
431  int ret_all = 0, ret;
432  unsigned i;
433 
434  for (i = 0; i < tee->nb_slaves; i++) {
435  avf2 = tee->slaves[i].avf;
436  if ((ret = av_write_trailer(avf2)) < 0)
437  if (!ret_all)
438  ret_all = ret;
439  if (!(avf2->oformat->flags & AVFMT_NOFILE)) {
440  if ((ret = avio_close(avf2->pb)) < 0)
441  if (!ret_all)
442  ret_all = ret;
443  avf2->pb = NULL;
444  }
445  }
446  close_slaves(avf);
447  return ret_all;
448 }
449 
451 {
452  TeeContext *tee = avf->priv_data;
453  AVFormatContext *avf2;
454  AVPacket pkt2;
455  int ret_all = 0, ret;
456  unsigned i, s;
457  int s2;
458  AVRational tb, tb2;
459 
460  for (i = 0; i < tee->nb_slaves; i++) {
461  avf2 = tee->slaves[i].avf;
462  s = pkt->stream_index;
463  s2 = tee->slaves[i].stream_map[s];
464  if (s2 < 0)
465  continue;
466 
467  if ((ret = av_copy_packet(&pkt2, pkt)) < 0 ||
468  (ret = av_dup_packet(&pkt2))< 0)
469  if (!ret_all) {
470  ret_all = ret;
471  continue;
472  }
473  tb = avf ->streams[s ]->time_base;
474  tb2 = avf2->streams[s2]->time_base;
475  pkt2.pts = av_rescale_q(pkt->pts, tb, tb2);
476  pkt2.dts = av_rescale_q(pkt->dts, tb, tb2);
477  pkt2.duration = av_rescale_q(pkt->duration, tb, tb2);
478  pkt2.stream_index = s2;
479 
480  filter_packet(avf2, &pkt2, avf2, tee->slaves[i].bsfs[s2]);
481  if ((ret = av_interleaved_write_frame(avf2, &pkt2)) < 0)
482  if (!ret_all)
483  ret_all = ret;
484  }
485  return ret_all;
486 }
487 
489  .name = "tee",
490  .long_name = NULL_IF_CONFIG_SMALL("Multiple muxer tee"),
491  .priv_data_size = sizeof(TeeContext),
495  .priv_class = &tee_muxer_class,
496  .flags = AVFMT_NOFILE,
497 };