Libav
hdsenc.c
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1 /*
2  * Live HDS fragmenter
3  * Copyright (c) 2013 Martin Storsjo
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 "config.h"
23 #include <float.h>
24 #if HAVE_UNISTD_H
25 #include <unistd.h>
26 #endif
27 
28 #include "avformat.h"
29 #include "internal.h"
30 #include "os_support.h"
31 
32 #include "libavutil/avstring.h"
33 #include "libavutil/base64.h"
34 #include "libavutil/intreadwrite.h"
35 #include "libavutil/mathematics.h"
36 #include "libavutil/opt.h"
37 
38 typedef struct Fragment {
39  char file[1024];
40  int64_t start_time, duration;
41  int n;
42 } Fragment;
43 
44 typedef struct OutputStream {
45  int bitrate;
49  uint8_t iobuf[32768];
50  char temp_filename[1024];
56 
58 
61 
65 } OutputStream;
66 
67 typedef struct HDSContext {
68  const AVClass *class; /* Class for private options. */
73 
76 } HDSContext;
77 
78 static int parse_header(OutputStream *os, const uint8_t *buf, int buf_size)
79 {
80  if (buf_size < 13)
81  return AVERROR_INVALIDDATA;
82  if (memcmp(buf, "FLV", 3))
83  return AVERROR_INVALIDDATA;
84  buf += 13;
85  buf_size -= 13;
86  while (buf_size >= 11 + 4) {
87  int type = buf[0];
88  int size = AV_RB24(&buf[1]) + 11 + 4;
89  if (size > buf_size)
90  return AVERROR_INVALIDDATA;
91  if (type == 8 || type == 9) {
93  return AVERROR_INVALIDDATA;
95  os->extra_packets[os->nb_extra_packets] = av_malloc(size);
96  if (!os->extra_packets[os->nb_extra_packets])
97  return AVERROR(ENOMEM);
98  memcpy(os->extra_packets[os->nb_extra_packets], buf, size);
99  os->nb_extra_packets++;
100  } else if (type == 0x12) {
101  if (os->metadata)
102  return AVERROR_INVALIDDATA;
103  os->metadata_size = size - 11 - 4;
104  os->metadata = av_malloc(os->metadata_size);
105  if (!os->metadata)
106  return AVERROR(ENOMEM);
107  memcpy(os->metadata, buf + 11, os->metadata_size);
108  }
109  buf += size;
110  buf_size -= size;
111  }
112  if (!os->metadata)
113  return AVERROR_INVALIDDATA;
114  return 0;
115 }
116 
117 static int hds_write(void *opaque, uint8_t *buf, int buf_size)
118 {
119  OutputStream *os = opaque;
120  if (os->out) {
121  avio_write(os->out, buf, buf_size);
122  } else {
123  if (!os->metadata_size) {
124  int ret;
125  // Assuming the IO buffer is large enough to fit the
126  // FLV header and all metadata and extradata packets
127  if ((ret = parse_header(os, buf, buf_size)) < 0)
128  return ret;
129  }
130  }
131  return buf_size;
132 }
133 
134 static void hds_free(AVFormatContext *s)
135 {
136  HDSContext *c = s->priv_data;
137  int i, j;
138  if (!c->streams)
139  return;
140  for (i = 0; i < s->nb_streams; i++) {
141  OutputStream *os = &c->streams[i];
142  if (os->out)
143  avio_close(os->out);
144  os->out = NULL;
145  if (os->ctx && os->ctx_inited)
146  av_write_trailer(os->ctx);
147  if (os->ctx && os->ctx->pb)
148  av_free(os->ctx->pb);
149  if (os->ctx)
151  av_free(os->metadata);
152  for (j = 0; j < os->nb_extra_packets; j++)
153  av_free(os->extra_packets[j]);
154  for (j = 0; j < os->nb_fragments; j++)
155  av_free(os->fragments[j]);
156  av_free(os->fragments);
157  }
158  av_freep(&c->streams);
159 }
160 
161 static int write_manifest(AVFormatContext *s, int final)
162 {
163  HDSContext *c = s->priv_data;
164  AVIOContext *out;
165  char filename[1024], temp_filename[1024];
166  int ret, i;
167  float duration = 0;
168 
169  if (c->nb_streams > 0)
170  duration = c->streams[0].last_ts * av_q2d(s->streams[0]->time_base);
171 
172  snprintf(filename, sizeof(filename), "%s/index.f4m", s->filename);
173  snprintf(temp_filename, sizeof(temp_filename), "%s/index.f4m.tmp", s->filename);
174  ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE,
175  &s->interrupt_callback, NULL);
176  if (ret < 0) {
177  av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", filename);
178  return ret;
179  }
180  avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
181  avio_printf(out, "<manifest xmlns=\"http://ns.adobe.com/f4m/1.0\">\n");
182  avio_printf(out, "\t<id>%s</id>\n", av_basename(s->filename));
183  avio_printf(out, "\t<streamType>%s</streamType>\n",
184  final ? "recorded" : "live");
185  avio_printf(out, "\t<deliveryType>streaming</deliveryType>\n");
186  if (final)
187  avio_printf(out, "\t<duration>%f</duration>\n", duration);
188  for (i = 0; i < c->nb_streams; i++) {
189  OutputStream *os = &c->streams[i];
190  int b64_size = AV_BASE64_SIZE(os->metadata_size);
191  char *base64 = av_malloc(b64_size);
192  if (!base64) {
193  avio_close(out);
194  return AVERROR(ENOMEM);
195  }
196  av_base64_encode(base64, b64_size, os->metadata, os->metadata_size);
197 
198  avio_printf(out, "\t<bootstrapInfo profile=\"named\" url=\"stream%d.abst\" id=\"bootstrap%d\" />\n", i, i);
199  avio_printf(out, "\t<media bitrate=\"%d\" url=\"stream%d\" bootstrapInfoId=\"bootstrap%d\">\n", os->bitrate/1000, i, i);
200  avio_printf(out, "\t\t<metadata>%s</metadata>\n", base64);
201  avio_printf(out, "\t</media>\n");
202  av_free(base64);
203  }
204  avio_printf(out, "</manifest>\n");
205  avio_flush(out);
206  avio_close(out);
207  rename(temp_filename, filename);
208  return 0;
209 }
210 
211 static void update_size(AVIOContext *out, int64_t pos)
212 {
213  int64_t end = avio_tell(out);
214  avio_seek(out, pos, SEEK_SET);
215  avio_wb32(out, end - pos);
216  avio_seek(out, end, SEEK_SET);
217 }
218 
219 /* Note, the .abst files need to be served with the "binary/octet"
220  * mime type, otherwise at least the OSMF player can easily fail
221  * with "stream not found" when polling for the next fragment. */
222 static int write_abst(AVFormatContext *s, OutputStream *os, int final)
223 {
224  HDSContext *c = s->priv_data;
225  AVIOContext *out;
226  char filename[1024], temp_filename[1024];
227  int i, ret;
228  int64_t asrt_pos, afrt_pos;
229  int start = 0, fragments;
230  int index = s->streams[os->first_stream]->id;
231  int64_t cur_media_time = 0;
232  if (c->window_size)
233  start = FFMAX(os->nb_fragments - c->window_size, 0);
234  fragments = os->nb_fragments - start;
235  if (final)
236  cur_media_time = os->last_ts;
237  else if (os->nb_fragments)
238  cur_media_time = os->fragments[os->nb_fragments - 1]->start_time;
239 
240  snprintf(filename, sizeof(filename),
241  "%s/stream%d.abst", s->filename, index);
242  snprintf(temp_filename, sizeof(temp_filename),
243  "%s/stream%d.abst.tmp", s->filename, index);
244  ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE,
245  &s->interrupt_callback, NULL);
246  if (ret < 0) {
247  av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
248  return ret;
249  }
250  avio_wb32(out, 0); // abst size
251  avio_wl32(out, MKTAG('a','b','s','t'));
252  avio_wb32(out, 0); // version + flags
253  avio_wb32(out, os->fragment_index - 1); // BootstrapinfoVersion
254  avio_w8(out, final ? 0 : 0x20); // profile, live, update
255  avio_wb32(out, 1000); // timescale
256  avio_wb64(out, cur_media_time);
257  avio_wb64(out, 0); // SmpteTimeCodeOffset
258  avio_w8(out, 0); // MovieIdentifer (null string)
259  avio_w8(out, 0); // ServerEntryCount
260  avio_w8(out, 0); // QualityEntryCount
261  avio_w8(out, 0); // DrmData (null string)
262  avio_w8(out, 0); // MetaData (null string)
263  avio_w8(out, 1); // SegmentRunTableCount
264  asrt_pos = avio_tell(out);
265  avio_wb32(out, 0); // asrt size
266  avio_wl32(out, MKTAG('a','s','r','t'));
267  avio_wb32(out, 0); // version + flags
268  avio_w8(out, 0); // QualityEntryCount
269  avio_wb32(out, 1); // SegmentRunEntryCount
270  avio_wb32(out, 1); // FirstSegment
271  avio_wb32(out, final ? (os->fragment_index - 1) : 0xffffffff); // FragmentsPerSegment
272  update_size(out, asrt_pos);
273  avio_w8(out, 1); // FragmentRunTableCount
274  afrt_pos = avio_tell(out);
275  avio_wb32(out, 0); // afrt size
276  avio_wl32(out, MKTAG('a','f','r','t'));
277  avio_wb32(out, 0); // version + flags
278  avio_wb32(out, 1000); // timescale
279  avio_w8(out, 0); // QualityEntryCount
280  avio_wb32(out, fragments); // FragmentRunEntryCount
281  for (i = start; i < os->nb_fragments; i++) {
282  avio_wb32(out, os->fragments[i]->n);
283  avio_wb64(out, os->fragments[i]->start_time);
284  avio_wb32(out, os->fragments[i]->duration);
285  }
286  update_size(out, afrt_pos);
287  update_size(out, 0);
288  avio_close(out);
289  rename(temp_filename, filename);
290  return 0;
291 }
292 
293 static int init_file(AVFormatContext *s, OutputStream *os, int64_t start_ts)
294 {
295  int ret, i;
296  ret = avio_open2(&os->out, os->temp_filename, AVIO_FLAG_WRITE,
297  &s->interrupt_callback, NULL);
298  if (ret < 0)
299  return ret;
300  avio_wb32(os->out, 0);
301  avio_wl32(os->out, MKTAG('m','d','a','t'));
302  for (i = 0; i < os->nb_extra_packets; i++) {
303  AV_WB24(os->extra_packets[i] + 4, start_ts);
304  os->extra_packets[i][7] = (start_ts >> 24) & 0x7f;
305  avio_write(os->out, os->extra_packets[i], os->extra_packet_sizes[i]);
306  }
307  return 0;
308 }
309 
310 static void close_file(OutputStream *os)
311 {
312  int64_t pos = avio_tell(os->out);
313  avio_seek(os->out, 0, SEEK_SET);
314  avio_wb32(os->out, pos);
315  avio_flush(os->out);
316  avio_close(os->out);
317  os->out = NULL;
318 }
319 
321 {
322  HDSContext *c = s->priv_data;
323  int ret = 0, i;
324  AVOutputFormat *oformat;
325 
326  mkdir(s->filename, 0777);
327 
328  oformat = av_guess_format("flv", NULL, NULL);
329  if (!oformat) {
331  goto fail;
332  }
333 
334  c->streams = av_mallocz(sizeof(*c->streams) * s->nb_streams);
335  if (!c->streams) {
336  ret = AVERROR(ENOMEM);
337  goto fail;
338  }
339 
340  for (i = 0; i < s->nb_streams; i++) {
341  OutputStream *os = &c->streams[c->nb_streams];
342  AVFormatContext *ctx;
343  AVStream *st = s->streams[i];
344 
345  if (!st->codec->bit_rate) {
346  av_log(s, AV_LOG_ERROR, "No bit rate set for stream %d\n", i);
347  ret = AVERROR(EINVAL);
348  goto fail;
349  }
350  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
351  if (os->has_video) {
352  c->nb_streams++;
353  os++;
354  }
355  os->has_video = 1;
356  } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
357  if (os->has_audio) {
358  c->nb_streams++;
359  os++;
360  }
361  os->has_audio = 1;
362  } else {
363  av_log(s, AV_LOG_ERROR, "Unsupported stream type in stream %d\n", i);
364  ret = AVERROR(EINVAL);
365  goto fail;
366  }
367  os->bitrate += s->streams[i]->codec->bit_rate;
368 
369  if (!os->ctx) {
370  os->first_stream = i;
371  ctx = avformat_alloc_context();
372  if (!ctx) {
373  ret = AVERROR(ENOMEM);
374  goto fail;
375  }
376  os->ctx = ctx;
377  ctx->oformat = oformat;
379 
380  ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf),
381  AVIO_FLAG_WRITE, os,
382  NULL, hds_write, NULL);
383  if (!ctx->pb) {
384  ret = AVERROR(ENOMEM);
385  goto fail;
386  }
387  } else {
388  ctx = os->ctx;
389  }
390  s->streams[i]->id = c->nb_streams;
391 
392  if (!(st = avformat_new_stream(ctx, NULL))) {
393  ret = AVERROR(ENOMEM);
394  goto fail;
395  }
398  }
399  if (c->streams[c->nb_streams].ctx)
400  c->nb_streams++;
401 
402  for (i = 0; i < c->nb_streams; i++) {
403  OutputStream *os = &c->streams[i];
404  int j;
405  if ((ret = avformat_write_header(os->ctx, NULL)) < 0) {
406  goto fail;
407  }
408  os->ctx_inited = 1;
409  avio_flush(os->ctx->pb);
410  for (j = 0; j < os->ctx->nb_streams; j++)
411  s->streams[os->first_stream + j]->time_base = os->ctx->streams[j]->time_base;
412 
413  snprintf(os->temp_filename, sizeof(os->temp_filename),
414  "%s/stream%d_temp", s->filename, i);
415  ret = init_file(s, os, 0);
416  if (ret < 0)
417  goto fail;
418 
419  if (!os->has_video && c->min_frag_duration <= 0) {
421  "No video stream in output stream %d and no min frag duration set\n", i);
422  ret = AVERROR(EINVAL);
423  }
424  os->fragment_index = 1;
425  write_abst(s, os, 0);
426  }
427  ret = write_manifest(s, 0);
428 
429 fail:
430  if (ret)
431  hds_free(s);
432  return ret;
433 }
434 
435 static int add_fragment(OutputStream *os, const char *file,
436  int64_t start_time, int64_t duration)
437 {
438  Fragment *frag;
439  if (duration == 0)
440  duration = 1;
441  if (os->nb_fragments >= os->fragments_size) {
442  int ret;
443  os->fragments_size = (os->fragments_size + 1) * 2;
444  if ((ret = av_reallocp_array(&os->fragments, os->fragments_size,
445  sizeof(*os->fragments))) < 0) {
446  os->fragments_size = 0;
447  os->nb_fragments = 0;
448  return ret;
449  }
450  }
451  frag = av_mallocz(sizeof(*frag));
452  if (!frag)
453  return AVERROR(ENOMEM);
454  av_strlcpy(frag->file, file, sizeof(frag->file));
455  frag->start_time = start_time;
456  frag->duration = duration;
457  frag->n = os->fragment_index;
458  os->fragments[os->nb_fragments++] = frag;
459  os->fragment_index++;
460  return 0;
461 }
462 
463 static int hds_flush(AVFormatContext *s, OutputStream *os, int final,
464  int64_t end_ts)
465 {
466  HDSContext *c = s->priv_data;
467  int i, ret = 0;
468  char target_filename[1024];
469  int index = s->streams[os->first_stream]->id;
470 
471  if (!os->packets_written)
472  return 0;
473 
474  avio_flush(os->ctx->pb);
475  os->packets_written = 0;
476  close_file(os);
477 
478  snprintf(target_filename, sizeof(target_filename),
479  "%s/stream%dSeg1-Frag%d", s->filename, index, os->fragment_index);
480  rename(os->temp_filename, target_filename);
481  add_fragment(os, target_filename, os->frag_start_ts, end_ts - os->frag_start_ts);
482 
483  if (!final) {
484  ret = init_file(s, os, end_ts);
485  if (ret < 0)
486  return ret;
487  }
488 
489  if (c->window_size || (final && c->remove_at_exit)) {
490  int remove = os->nb_fragments - c->window_size - c->extra_window_size;
491  if (final && c->remove_at_exit)
492  remove = os->nb_fragments;
493  if (remove > 0) {
494  for (i = 0; i < remove; i++) {
495  unlink(os->fragments[i]->file);
496  av_free(os->fragments[i]);
497  }
498  os->nb_fragments -= remove;
499  memmove(os->fragments, os->fragments + remove,
500  os->nb_fragments * sizeof(*os->fragments));
501  }
502  }
503 
504  if (ret >= 0)
505  ret = write_abst(s, os, final);
506  return ret;
507 }
508 
510 {
511  HDSContext *c = s->priv_data;
512  AVStream *st = s->streams[pkt->stream_index];
513  OutputStream *os = &c->streams[s->streams[pkt->stream_index]->id];
514  int64_t end_dts = os->fragment_index * (int64_t) c->min_frag_duration;
515  int ret;
516 
517  if (st->first_dts == AV_NOPTS_VALUE)
518  st->first_dts = pkt->dts;
519 
520  if ((!os->has_video || st->codec->codec_type == AVMEDIA_TYPE_VIDEO) &&
521  av_compare_ts(pkt->dts - st->first_dts, st->time_base,
522  end_dts, AV_TIME_BASE_Q) >= 0 &&
523  pkt->flags & AV_PKT_FLAG_KEY && os->packets_written) {
524 
525  if ((ret = hds_flush(s, os, 0, pkt->dts)) < 0)
526  return ret;
527  }
528 
529  // Note, these fragment start timestamps, that represent a whole
530  // OutputStream, assume all streams in it have the same time base.
531  if (!os->packets_written)
532  os->frag_start_ts = pkt->dts;
533  os->last_ts = pkt->dts;
534 
535  os->packets_written++;
536  return ff_write_chained(os->ctx, pkt->stream_index - os->first_stream, pkt, s);
537 }
538 
540 {
541  HDSContext *c = s->priv_data;
542  int i;
543 
544  for (i = 0; i < c->nb_streams; i++)
545  hds_flush(s, &c->streams[i], 1, c->streams[i].last_ts);
546  write_manifest(s, 1);
547 
548  if (c->remove_at_exit) {
549  char filename[1024];
550  snprintf(filename, sizeof(filename), "%s/index.f4m", s->filename);
551  unlink(filename);
552  for (i = 0; i < c->nb_streams; i++) {
553  snprintf(filename, sizeof(filename), "%s/stream%d.abst", s->filename, i);
554  unlink(filename);
555  }
556  rmdir(s->filename);
557  }
558 
559  hds_free(s);
560  return 0;
561 }
562 
563 #define OFFSET(x) offsetof(HDSContext, x)
564 #define E AV_OPT_FLAG_ENCODING_PARAM
565 static const AVOption options[] = {
566  { "window_size", "number of fragments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E },
567  { "extra_window_size", "number of fragments kept outside of the manifest before removing from disk", OFFSET(extra_window_size), AV_OPT_TYPE_INT, { .i64 = 5 }, 0, INT_MAX, E },
568  { "min_frag_duration", "minimum fragment duration (in microseconds)", OFFSET(min_frag_duration), AV_OPT_TYPE_INT64, { .i64 = 10000000 }, 0, INT_MAX, E },
569  { "remove_at_exit", "remove all fragments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
570  { NULL },
571 };
572 
573 static const AVClass hds_class = {
574  .class_name = "HDS muxer",
575  .item_name = av_default_item_name,
576  .option = options,
577  .version = LIBAVUTIL_VERSION_INT,
578 };
579 
581  .name = "hds",
582  .long_name = NULL_IF_CONFIG_SMALL("HDS Muxer"),
583  .priv_data_size = sizeof(HDSContext),
584  .audio_codec = AV_CODEC_ID_AAC,
585  .video_codec = AV_CODEC_ID_H264,
590  .priv_class = &hds_class,
591 };