mpegtsenc.c
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1 /*
2  * MPEG2 transport stream (aka DVB) muxer
3  * Copyright (c) 2003 Fabrice Bellard
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/bswap.h"
23 #include "libavutil/crc.h"
24 #include "libavutil/dict.h"
25 #include "libavutil/mathematics.h"
26 #include "libavutil/opt.h"
27 #include "libavcodec/mpegvideo.h"
28 #include "avformat.h"
29 #include "internal.h"
30 #include "mpegts.h"
31 #include "adts.h"
32 
33 #define PCR_TIME_BASE 27000000
34 
35 /* write DVB SI sections */
36 
37 /*********************************************/
38 /* mpegts section writer */
39 
40 typedef struct MpegTSSection {
41  int pid;
42  int cc;
43  void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
44  void *opaque;
46 
47 typedef struct MpegTSService {
48  MpegTSSection pmt; /* MPEG2 pmt table context */
49  int sid; /* service ID */
50  char *name;
52  int pcr_pid;
56 
57 typedef struct MpegTSWrite {
58  const AVClass *av_class;
59  MpegTSSection pat; /* MPEG2 pat table */
60  MpegTSSection sdt; /* MPEG2 sdt table context */
67  int onid;
68  int tsid;
69  int64_t first_pcr;
70  int mux_rate;
72 
76 
78  int start_pid;
79 } MpegTSWrite;
80 
81 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
82 #define DEFAULT_PES_HEADER_FREQ 16
83 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
84 
85 static const AVOption options[] = {
86  { "mpegts_transport_stream_id", "Set transport_stream_id field.",
87  offsetof(MpegTSWrite, transport_stream_id), AV_OPT_TYPE_INT, {.dbl = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},
88  { "mpegts_original_network_id", "Set original_network_id field.",
89  offsetof(MpegTSWrite, original_network_id), AV_OPT_TYPE_INT, {.dbl = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},
90  { "mpegts_service_id", "Set service_id field.",
91  offsetof(MpegTSWrite, service_id), AV_OPT_TYPE_INT, {.dbl = 0x0001 }, 0x0001, 0xffff, AV_OPT_FLAG_ENCODING_PARAM},
92  { "mpegts_pmt_start_pid", "Set the first pid of the PMT.",
93  offsetof(MpegTSWrite, pmt_start_pid), AV_OPT_TYPE_INT, {.dbl = 0x1000 }, 0x1000, 0x1f00, AV_OPT_FLAG_ENCODING_PARAM},
94  { "mpegts_start_pid", "Set the first pid.",
95  offsetof(MpegTSWrite, start_pid), AV_OPT_TYPE_INT, {.dbl = 0x0100 }, 0x0100, 0x0f00, AV_OPT_FLAG_ENCODING_PARAM},
96  { "muxrate", NULL, offsetof(MpegTSWrite, mux_rate), AV_OPT_TYPE_INT, {1}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},
97  { "pes_payload_size", "Minimum PES packet payload in bytes",
98  offsetof(MpegTSWrite, pes_payload_size), AV_OPT_TYPE_INT, {DEFAULT_PES_PAYLOAD_SIZE}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},
99  { NULL },
100 };
101 
102 static const AVClass mpegts_muxer_class = {
103  .class_name = "MPEGTS muxer",
104  .item_name = av_default_item_name,
105  .option = options,
106  .version = LIBAVUTIL_VERSION_INT,
107 };
108 
109 /* NOTE: 4 bytes must be left at the end for the crc32 */
110 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
111 {
112  unsigned int crc;
113  unsigned char packet[TS_PACKET_SIZE];
114  const unsigned char *buf_ptr;
115  unsigned char *q;
116  int first, b, len1, left;
117 
118  crc = av_bswap32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
119  buf[len - 4] = (crc >> 24) & 0xff;
120  buf[len - 3] = (crc >> 16) & 0xff;
121  buf[len - 2] = (crc >> 8) & 0xff;
122  buf[len - 1] = (crc) & 0xff;
123 
124  /* send each packet */
125  buf_ptr = buf;
126  while (len > 0) {
127  first = (buf == buf_ptr);
128  q = packet;
129  *q++ = 0x47;
130  b = (s->pid >> 8);
131  if (first)
132  b |= 0x40;
133  *q++ = b;
134  *q++ = s->pid;
135  s->cc = (s->cc + 1) & 0xf;
136  *q++ = 0x10 | s->cc;
137  if (first)
138  *q++ = 0; /* 0 offset */
139  len1 = TS_PACKET_SIZE - (q - packet);
140  if (len1 > len)
141  len1 = len;
142  memcpy(q, buf_ptr, len1);
143  q += len1;
144  /* add known padding data */
145  left = TS_PACKET_SIZE - (q - packet);
146  if (left > 0)
147  memset(q, 0xff, left);
148 
149  s->write_packet(s, packet);
150 
151  buf_ptr += len1;
152  len -= len1;
153  }
154 }
155 
156 static inline void put16(uint8_t **q_ptr, int val)
157 {
158  uint8_t *q;
159  q = *q_ptr;
160  *q++ = val >> 8;
161  *q++ = val;
162  *q_ptr = q;
163 }
164 
165 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
166  int version, int sec_num, int last_sec_num,
167  uint8_t *buf, int len)
168 {
169  uint8_t section[1024], *q;
170  unsigned int tot_len;
171  /* reserved_future_use field must be set to 1 for SDT */
172  unsigned int flags = tid == SDT_TID ? 0xf000 : 0xb000;
173 
174  tot_len = 3 + 5 + len + 4;
175  /* check if not too big */
176  if (tot_len > 1024)
177  return -1;
178 
179  q = section;
180  *q++ = tid;
181  put16(&q, flags | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
182  put16(&q, id);
183  *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
184  *q++ = sec_num;
185  *q++ = last_sec_num;
186  memcpy(q, buf, len);
187 
188  mpegts_write_section(s, section, tot_len);
189  return 0;
190 }
191 
192 /*********************************************/
193 /* mpegts writer */
194 
195 #define DEFAULT_PROVIDER_NAME "Libav"
196 #define DEFAULT_SERVICE_NAME "Service01"
197 
198 /* we retransmit the SI info at this rate */
199 #define SDT_RETRANS_TIME 500
200 #define PAT_RETRANS_TIME 100
201 #define PCR_RETRANS_TIME 20
202 
203 typedef struct MpegTSWriteStream {
205  int pid; /* stream associated pid */
206  int cc;
209  int64_t payload_pts;
210  int64_t payload_dts;
212  uint8_t *payload;
215 
217 {
218  MpegTSWrite *ts = s->priv_data;
219  MpegTSService *service;
220  uint8_t data[1012], *q;
221  int i;
222 
223  q = data;
224  for(i = 0; i < ts->nb_services; i++) {
225  service = ts->services[i];
226  put16(&q, service->sid);
227  put16(&q, 0xe000 | service->pmt.pid);
228  }
229  mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
230  data, q - data);
231 }
232 
234 {
235  // MpegTSWrite *ts = s->priv_data;
236  uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
237  int val, stream_type, i;
238 
239  q = data;
240  put16(&q, 0xe000 | service->pcr_pid);
241 
242  program_info_length_ptr = q;
243  q += 2; /* patched after */
244 
245  /* put program info here */
246 
247  val = 0xf000 | (q - program_info_length_ptr - 2);
248  program_info_length_ptr[0] = val >> 8;
249  program_info_length_ptr[1] = val;
250 
251  for(i = 0; i < s->nb_streams; i++) {
252  AVStream *st = s->streams[i];
253  MpegTSWriteStream *ts_st = st->priv_data;
254  AVDictionaryEntry *lang = av_dict_get(st->metadata, "language", NULL,0);
255  switch(st->codec->codec_id) {
256  case CODEC_ID_MPEG1VIDEO:
257  case CODEC_ID_MPEG2VIDEO:
258  stream_type = STREAM_TYPE_VIDEO_MPEG2;
259  break;
260  case CODEC_ID_MPEG4:
261  stream_type = STREAM_TYPE_VIDEO_MPEG4;
262  break;
263  case CODEC_ID_H264:
264  stream_type = STREAM_TYPE_VIDEO_H264;
265  break;
266  case CODEC_ID_DIRAC:
267  stream_type = STREAM_TYPE_VIDEO_DIRAC;
268  break;
269  case CODEC_ID_MP2:
270  case CODEC_ID_MP3:
271  stream_type = STREAM_TYPE_AUDIO_MPEG1;
272  break;
273  case CODEC_ID_AAC:
274  stream_type = STREAM_TYPE_AUDIO_AAC;
275  break;
276  case CODEC_ID_AAC_LATM:
277  stream_type = STREAM_TYPE_AUDIO_AAC_LATM;
278  break;
279  case CODEC_ID_AC3:
280  stream_type = STREAM_TYPE_AUDIO_AC3;
281  break;
282  default:
283  stream_type = STREAM_TYPE_PRIVATE_DATA;
284  break;
285  }
286  *q++ = stream_type;
287  put16(&q, 0xe000 | ts_st->pid);
288  desc_length_ptr = q;
289  q += 2; /* patched after */
290 
291  /* write optional descriptors here */
292  switch(st->codec->codec_type) {
293  case AVMEDIA_TYPE_AUDIO:
294  if (lang) {
295  char *p;
296  char *next = lang->value;
297  uint8_t *len_ptr;
298 
299  *q++ = 0x0a; /* ISO 639 language descriptor */
300  len_ptr = q++;
301  *len_ptr = 0;
302 
303  for (p = lang->value; next && *len_ptr < 255 / 4 * 4; p = next + 1) {
304  next = strchr(p, ',');
305  if (strlen(p) != 3 && (!next || next != p + 3))
306  continue; /* not a 3-letter code */
307 
308  *q++ = *p++;
309  *q++ = *p++;
310  *q++ = *p++;
311 
313  *q++ = 0x01;
315  *q++ = 0x02;
317  *q++ = 0x03;
318  else
319  *q++ = 0; /* undefined type */
320 
321  *len_ptr += 4;
322  }
323 
324  if (*len_ptr == 0)
325  q -= 2; /* no language codes were written */
326  }
327  break;
329  {
330  const char *language;
331  language = lang && strlen(lang->value)==3 ? lang->value : "eng";
332  *q++ = 0x59;
333  *q++ = 8;
334  *q++ = language[0];
335  *q++ = language[1];
336  *q++ = language[2];
337  *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
338  if(st->codec->extradata_size == 4) {
339  memcpy(q, st->codec->extradata, 4);
340  q += 4;
341  } else {
342  put16(&q, 1); /* page id */
343  put16(&q, 1); /* ancillary page id */
344  }
345  }
346  break;
347  case AVMEDIA_TYPE_VIDEO:
348  if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
349  *q++ = 0x05; /*MPEG-2 registration descriptor*/
350  *q++ = 4;
351  *q++ = 'd';
352  *q++ = 'r';
353  *q++ = 'a';
354  *q++ = 'c';
355  }
356  break;
357  }
358 
359  val = 0xf000 | (q - desc_length_ptr - 2);
360  desc_length_ptr[0] = val >> 8;
361  desc_length_ptr[1] = val;
362  }
363  mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
364  data, q - data);
365 }
366 
367 /* NOTE: str == NULL is accepted for an empty string */
368 static void putstr8(uint8_t **q_ptr, const char *str)
369 {
370  uint8_t *q;
371  int len;
372 
373  q = *q_ptr;
374  if (!str)
375  len = 0;
376  else
377  len = strlen(str);
378  *q++ = len;
379  memcpy(q, str, len);
380  q += len;
381  *q_ptr = q;
382 }
383 
385 {
386  MpegTSWrite *ts = s->priv_data;
387  MpegTSService *service;
388  uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
389  int i, running_status, free_ca_mode, val;
390 
391  q = data;
392  put16(&q, ts->onid);
393  *q++ = 0xff;
394  for(i = 0; i < ts->nb_services; i++) {
395  service = ts->services[i];
396  put16(&q, service->sid);
397  *q++ = 0xfc | 0x00; /* currently no EIT info */
398  desc_list_len_ptr = q;
399  q += 2;
400  running_status = 4; /* running */
401  free_ca_mode = 0;
402 
403  /* write only one descriptor for the service name and provider */
404  *q++ = 0x48;
405  desc_len_ptr = q;
406  q++;
407  *q++ = 0x01; /* digital television service */
408  putstr8(&q, service->provider_name);
409  putstr8(&q, service->name);
410  desc_len_ptr[0] = q - desc_len_ptr - 1;
411 
412  /* fill descriptor length */
413  val = (running_status << 13) | (free_ca_mode << 12) |
414  (q - desc_list_len_ptr - 2);
415  desc_list_len_ptr[0] = val >> 8;
416  desc_list_len_ptr[1] = val;
417  }
418  mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
419  data, q - data);
420 }
421 
423  int sid,
424  const char *provider_name,
425  const char *name)
426 {
427  MpegTSService *service;
428 
429  service = av_mallocz(sizeof(MpegTSService));
430  if (!service)
431  return NULL;
432  service->pmt.pid = ts->pmt_start_pid + ts->nb_services;
433  service->sid = sid;
434  service->provider_name = av_strdup(provider_name);
435  service->name = av_strdup(name);
436  service->pcr_pid = 0x1fff;
437  dynarray_add(&ts->services, &ts->nb_services, service);
438  return service;
439 }
440 
441 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
442 {
443  AVFormatContext *ctx = s->opaque;
444  avio_write(ctx->pb, packet, TS_PACKET_SIZE);
445 }
446 
448 {
449  MpegTSWrite *ts = s->priv_data;
450  MpegTSWriteStream *ts_st;
451  MpegTSService *service;
452  AVStream *st, *pcr_st = NULL;
453  AVDictionaryEntry *title, *provider;
454  int i, j;
455  const char *service_name;
456  const char *provider_name;
457  int *pids;
458 
459  // round up to a whole number of TS packets
460  ts->pes_payload_size = (ts->pes_payload_size + 14 + 183) / 184 * 184 - 14;
461 
462  ts->tsid = ts->transport_stream_id;
463  ts->onid = ts->original_network_id;
464  /* allocate a single DVB service */
465  title = av_dict_get(s->metadata, "service_name", NULL, 0);
466  if (!title)
467  title = av_dict_get(s->metadata, "title", NULL, 0);
468  service_name = title ? title->value : DEFAULT_SERVICE_NAME;
469  provider = av_dict_get(s->metadata, "service_provider", NULL, 0);
470  provider_name = provider ? provider->value : DEFAULT_PROVIDER_NAME;
471  service = mpegts_add_service(ts, ts->service_id, provider_name, service_name);
473  service->pmt.opaque = s;
474  service->pmt.cc = 15;
475 
476  ts->pat.pid = PAT_PID;
477  ts->pat.cc = 15; // Initialize at 15 so that it wraps and be equal to 0 for the first packet we write
479  ts->pat.opaque = s;
480 
481  ts->sdt.pid = SDT_PID;
482  ts->sdt.cc = 15;
484  ts->sdt.opaque = s;
485 
486  pids = av_malloc(s->nb_streams * sizeof(*pids));
487  if (!pids)
488  return AVERROR(ENOMEM);
489 
490  /* assign pids to each stream */
491  for(i = 0;i < s->nb_streams; i++) {
492  st = s->streams[i];
493  avpriv_set_pts_info(st, 33, 1, 90000);
494  ts_st = av_mallocz(sizeof(MpegTSWriteStream));
495  if (!ts_st)
496  goto fail;
497  st->priv_data = ts_st;
498  ts_st->payload = av_mallocz(ts->pes_payload_size);
499  if (!ts_st->payload)
500  goto fail;
501  ts_st->service = service;
502  /* MPEG pid values < 16 are reserved. Applications which set st->id in
503  * this range are assigned a calculated pid. */
504  if (st->id < 16) {
505  ts_st->pid = ts->start_pid + i;
506  } else if (st->id < 0x1FFF) {
507  ts_st->pid = st->id;
508  } else {
509  av_log(s, AV_LOG_ERROR, "Invalid stream id %d, must be less than 8191\n", st->id);
510  goto fail;
511  }
512  if (ts_st->pid == service->pmt.pid) {
513  av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
514  goto fail;
515  }
516  for (j = 0; j < i; j++)
517  if (pids[j] == ts_st->pid) {
518  av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
519  goto fail;
520  }
521  pids[i] = ts_st->pid;
522  ts_st->payload_pts = AV_NOPTS_VALUE;
523  ts_st->payload_dts = AV_NOPTS_VALUE;
524  ts_st->first_pts_check = 1;
525  ts_st->cc = 15;
526  /* update PCR pid by using the first video stream */
527  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
528  service->pcr_pid == 0x1fff) {
529  service->pcr_pid = ts_st->pid;
530  pcr_st = st;
531  }
532  if (st->codec->codec_id == CODEC_ID_AAC &&
533  st->codec->extradata_size > 0) {
534  ts_st->adts = av_mallocz(sizeof(*ts_st->adts));
535  if (!ts_st->adts)
536  goto fail;
537  if (ff_adts_decode_extradata(s, ts_st->adts, st->codec->extradata,
538  st->codec->extradata_size) < 0)
539  goto fail;
540  }
541  }
542 
543  av_free(pids);
544 
545  /* if no video stream, use the first stream as PCR */
546  if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
547  pcr_st = s->streams[0];
548  ts_st = pcr_st->priv_data;
549  service->pcr_pid = ts_st->pid;
550  }
551 
552 #if FF_API_MUXRATE
553  if (s->mux_rate)
554  ts->mux_rate = s->mux_rate;
555 #endif
556 
557  if (ts->mux_rate > 1) {
558  service->pcr_packet_period = (ts->mux_rate * PCR_RETRANS_TIME) /
559  (TS_PACKET_SIZE * 8 * 1000);
561  (TS_PACKET_SIZE * 8 * 1000);
563  (TS_PACKET_SIZE * 8 * 1000);
564 
566  } else {
567  /* Arbitrary values, PAT/PMT could be written on key frames */
568  ts->sdt_packet_period = 200;
569  ts->pat_packet_period = 40;
570  if (pcr_st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
571  if (!pcr_st->codec->frame_size) {
572  av_log(s, AV_LOG_WARNING, "frame size not set\n");
573  service->pcr_packet_period =
574  pcr_st->codec->sample_rate/(10*512);
575  } else {
576  service->pcr_packet_period =
577  pcr_st->codec->sample_rate/(10*pcr_st->codec->frame_size);
578  }
579  } else {
580  // max delta PCR 0.1s
581  service->pcr_packet_period =
582  pcr_st->codec->time_base.den/(10*pcr_st->codec->time_base.num);
583  }
584  }
585 
586  // output a PCR as soon as possible
587  service->pcr_packet_count = service->pcr_packet_period;
590 
591  if (ts->mux_rate == 1)
592  av_log(s, AV_LOG_INFO, "muxrate VBR, ");
593  else
594  av_log(s, AV_LOG_INFO, "muxrate %d, ", ts->mux_rate);
595  av_log(s, AV_LOG_INFO, "pcr every %d pkts, "
596  "sdt every %d, pat/pmt every %d pkts\n",
597  service->pcr_packet_period,
599 
600  avio_flush(s->pb);
601 
602  return 0;
603 
604  fail:
605  av_free(pids);
606  for(i = 0;i < s->nb_streams; i++) {
607  MpegTSWriteStream *ts_st;
608  st = s->streams[i];
609  ts_st = st->priv_data;
610  if (ts_st) {
611  av_freep(&ts_st->payload);
612  av_freep(&ts_st->adts);
613  }
614  av_freep(&st->priv_data);
615  }
616  return -1;
617 }
618 
619 /* send SDT, PAT and PMT tables regulary */
621 {
622  MpegTSWrite *ts = s->priv_data;
623  int i;
624 
625  if (++ts->sdt_packet_count == ts->sdt_packet_period) {
626  ts->sdt_packet_count = 0;
627  mpegts_write_sdt(s);
628  }
629  if (++ts->pat_packet_count == ts->pat_packet_period) {
630  ts->pat_packet_count = 0;
631  mpegts_write_pat(s);
632  for(i = 0; i < ts->nb_services; i++) {
633  mpegts_write_pmt(s, ts->services[i]);
634  }
635  }
636 }
637 
638 static int64_t get_pcr(const MpegTSWrite *ts, AVIOContext *pb)
639 {
640  return av_rescale(avio_tell(pb) + 11, 8 * PCR_TIME_BASE, ts->mux_rate) +
641  ts->first_pcr;
642 }
643 
644 static int write_pcr_bits(uint8_t *buf, int64_t pcr)
645 {
646  int64_t pcr_low = pcr % 300, pcr_high = pcr / 300;
647 
648  *buf++ = pcr_high >> 25;
649  *buf++ = pcr_high >> 17;
650  *buf++ = pcr_high >> 9;
651  *buf++ = pcr_high >> 1;
652  *buf++ = pcr_high << 7 | pcr_low >> 8 | 0x7e;
653  *buf++ = pcr_low;
654 
655  return 6;
656 }
657 
658 /* Write a single null transport stream packet */
660 {
661  uint8_t *q;
662  uint8_t buf[TS_PACKET_SIZE];
663 
664  q = buf;
665  *q++ = 0x47;
666  *q++ = 0x00 | 0x1f;
667  *q++ = 0xff;
668  *q++ = 0x10;
669  memset(q, 0x0FF, TS_PACKET_SIZE - (q - buf));
670  avio_write(s->pb, buf, TS_PACKET_SIZE);
671 }
672 
673 /* Write a single transport stream packet with a PCR and no payload */
675 {
676  MpegTSWrite *ts = s->priv_data;
677  MpegTSWriteStream *ts_st = st->priv_data;
678  uint8_t *q;
679  uint8_t buf[TS_PACKET_SIZE];
680 
681  q = buf;
682  *q++ = 0x47;
683  *q++ = ts_st->pid >> 8;
684  *q++ = ts_st->pid;
685  *q++ = 0x20 | ts_st->cc; /* Adaptation only */
686  /* Continuity Count field does not increment (see 13818-1 section 2.4.3.3) */
687  *q++ = TS_PACKET_SIZE - 5; /* Adaptation Field Length */
688  *q++ = 0x10; /* Adaptation flags: PCR present */
689 
690  /* PCR coded into 6 bytes */
691  q += write_pcr_bits(q, get_pcr(ts, s->pb));
692 
693  /* stuffing bytes */
694  memset(q, 0xFF, TS_PACKET_SIZE - (q - buf));
695  avio_write(s->pb, buf, TS_PACKET_SIZE);
696 }
697 
698 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
699 {
700  int val;
701 
702  val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
703  *q++ = val;
704  val = (((pts >> 15) & 0x7fff) << 1) | 1;
705  *q++ = val >> 8;
706  *q++ = val;
707  val = (((pts) & 0x7fff) << 1) | 1;
708  *q++ = val >> 8;
709  *q++ = val;
710 }
711 
712 /* Set an adaptation field flag in an MPEG-TS packet*/
713 static void set_af_flag(uint8_t *pkt, int flag)
714 {
715  // expect at least one flag to set
716  assert(flag);
717 
718  if ((pkt[3] & 0x20) == 0) {
719  // no AF yet, set adaptation field flag
720  pkt[3] |= 0x20;
721  // 1 byte length, no flags
722  pkt[4] = 1;
723  pkt[5] = 0;
724  }
725  pkt[5] |= flag;
726 }
727 
728 /* Extend the adaptation field by size bytes */
729 static void extend_af(uint8_t *pkt, int size)
730 {
731  // expect already existing adaptation field
732  assert(pkt[3] & 0x20);
733  pkt[4] += size;
734 }
735 
736 /* Get a pointer to MPEG-TS payload (right after TS packet header) */
737 static uint8_t *get_ts_payload_start(uint8_t *pkt)
738 {
739  if (pkt[3] & 0x20)
740  return pkt + 5 + pkt[4];
741  else
742  return pkt + 4;
743 }
744 
745 /* Add a pes header to the front of payload, and segment into an integer number of
746  * ts packets. The final ts packet is padded using an over-sized adaptation header
747  * to exactly fill the last ts packet.
748  * NOTE: 'payload' contains a complete PES payload.
749  */
751  const uint8_t *payload, int payload_size,
752  int64_t pts, int64_t dts, int key)
753 {
754  MpegTSWriteStream *ts_st = st->priv_data;
755  MpegTSWrite *ts = s->priv_data;
756  uint8_t buf[TS_PACKET_SIZE];
757  uint8_t *q;
758  int val, is_start, len, header_len, write_pcr, private_code, flags;
759  int afc_len, stuffing_len;
760  int64_t pcr = -1; /* avoid warning */
761  int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);
762 
763  is_start = 1;
764  while (payload_size > 0) {
766 
767  write_pcr = 0;
768  if (ts_st->pid == ts_st->service->pcr_pid) {
769  if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on frames
770  ts_st->service->pcr_packet_count++;
771  if (ts_st->service->pcr_packet_count >=
772  ts_st->service->pcr_packet_period) {
773  ts_st->service->pcr_packet_count = 0;
774  write_pcr = 1;
775  }
776  }
777 
778  if (ts->mux_rate > 1 && dts != AV_NOPTS_VALUE &&
779  (dts - get_pcr(ts, s->pb)/300) > delay) {
780  /* pcr insert gets priority over null packet insert */
781  if (write_pcr)
782  mpegts_insert_pcr_only(s, st);
783  else
785  continue; /* recalculate write_pcr and possibly retransmit si_info */
786  }
787 
788  /* prepare packet header */
789  q = buf;
790  *q++ = 0x47;
791  val = (ts_st->pid >> 8);
792  if (is_start)
793  val |= 0x40;
794  *q++ = val;
795  *q++ = ts_st->pid;
796  ts_st->cc = (ts_st->cc + 1) & 0xf;
797  *q++ = 0x10 | ts_st->cc; // payload indicator + CC
798  if (key && is_start && pts != AV_NOPTS_VALUE) {
799  // set Random Access for key frames
800  if (ts_st->pid == ts_st->service->pcr_pid)
801  write_pcr = 1;
802  set_af_flag(buf, 0x40);
803  q = get_ts_payload_start(buf);
804  }
805  if (write_pcr) {
806  set_af_flag(buf, 0x10);
807  q = get_ts_payload_start(buf);
808  // add 11, pcr references the last byte of program clock reference base
809  if (ts->mux_rate > 1)
810  pcr = get_pcr(ts, s->pb);
811  else
812  pcr = (dts - delay)*300;
813  if (dts != AV_NOPTS_VALUE && dts < pcr / 300)
814  av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");
815  extend_af(buf, write_pcr_bits(q, pcr));
816  q = get_ts_payload_start(buf);
817  }
818  if (is_start) {
819  int pes_extension = 0;
820  /* write PES header */
821  *q++ = 0x00;
822  *q++ = 0x00;
823  *q++ = 0x01;
824  private_code = 0;
825  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
826  if (st->codec->codec_id == CODEC_ID_DIRAC) {
827  *q++ = 0xfd;
828  } else
829  *q++ = 0xe0;
830  } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
831  (st->codec->codec_id == CODEC_ID_MP2 ||
832  st->codec->codec_id == CODEC_ID_MP3 ||
833  st->codec->codec_id == CODEC_ID_AAC)) {
834  *q++ = 0xc0;
835  } else {
836  *q++ = 0xbd;
837  if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
838  private_code = 0x20;
839  }
840  }
841  header_len = 0;
842  flags = 0;
843  if (pts != AV_NOPTS_VALUE) {
844  header_len += 5;
845  flags |= 0x80;
846  }
847  if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
848  header_len += 5;
849  flags |= 0x40;
850  }
851  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
852  st->codec->codec_id == CODEC_ID_DIRAC) {
853  /* set PES_extension_flag */
854  pes_extension = 1;
855  flags |= 0x01;
856 
857  /*
858  * One byte for PES2 extension flag +
859  * one byte for extension length +
860  * one byte for extension id
861  */
862  header_len += 3;
863  }
864  len = payload_size + header_len + 3;
865  if (private_code != 0)
866  len++;
867  if (len > 0xffff)
868  len = 0;
869  *q++ = len >> 8;
870  *q++ = len;
871  val = 0x80;
872  /* data alignment indicator is required for subtitle data */
874  val |= 0x04;
875  *q++ = val;
876  *q++ = flags;
877  *q++ = header_len;
878  if (pts != AV_NOPTS_VALUE) {
879  write_pts(q, flags >> 6, pts);
880  q += 5;
881  }
882  if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
883  write_pts(q, 1, dts);
884  q += 5;
885  }
886  if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {
887  flags = 0x01; /* set PES_extension_flag_2 */
888  *q++ = flags;
889  *q++ = 0x80 | 0x01; /* marker bit + extension length */
890  /*
891  * Set the stream id extension flag bit to 0 and
892  * write the extended stream id
893  */
894  *q++ = 0x00 | 0x60;
895  }
896  if (private_code != 0)
897  *q++ = private_code;
898  is_start = 0;
899  }
900  /* header size */
901  header_len = q - buf;
902  /* data len */
903  len = TS_PACKET_SIZE - header_len;
904  if (len > payload_size)
905  len = payload_size;
906  stuffing_len = TS_PACKET_SIZE - header_len - len;
907  if (stuffing_len > 0) {
908  /* add stuffing with AFC */
909  if (buf[3] & 0x20) {
910  /* stuffing already present: increase its size */
911  afc_len = buf[4] + 1;
912  memmove(buf + 4 + afc_len + stuffing_len,
913  buf + 4 + afc_len,
914  header_len - (4 + afc_len));
915  buf[4] += stuffing_len;
916  memset(buf + 4 + afc_len, 0xff, stuffing_len);
917  } else {
918  /* add stuffing */
919  memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
920  buf[3] |= 0x20;
921  buf[4] = stuffing_len - 1;
922  if (stuffing_len >= 2) {
923  buf[5] = 0x00;
924  memset(buf + 6, 0xff, stuffing_len - 2);
925  }
926  }
927  }
928  memcpy(buf + TS_PACKET_SIZE - len, payload, len);
929  payload += len;
930  payload_size -= len;
931  avio_write(s->pb, buf, TS_PACKET_SIZE);
932  }
933  avio_flush(s->pb);
934 }
935 
937 {
938  AVStream *st = s->streams[pkt->stream_index];
939  int size = pkt->size;
940  uint8_t *buf= pkt->data;
941  uint8_t *data= NULL;
942  MpegTSWrite *ts = s->priv_data;
943  MpegTSWriteStream *ts_st = st->priv_data;
944  const uint64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE)*2;
945  int64_t dts = AV_NOPTS_VALUE, pts = AV_NOPTS_VALUE;
946 
947  if (pkt->pts != AV_NOPTS_VALUE)
948  pts = pkt->pts + delay;
949  if (pkt->dts != AV_NOPTS_VALUE)
950  dts = pkt->dts + delay;
951 
952  if (ts_st->first_pts_check && pts == AV_NOPTS_VALUE) {
953  av_log(s, AV_LOG_ERROR, "first pts value must set\n");
954  return -1;
955  }
956  ts_st->first_pts_check = 0;
957 
958  if (st->codec->codec_id == CODEC_ID_H264) {
959  const uint8_t *p = buf, *buf_end = p+size;
960  uint32_t state = -1;
961 
962  if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {
963  av_log(s, AV_LOG_ERROR, "H.264 bitstream malformed, "
964  "no startcode found, use -vbsf h264_mp4toannexb\n");
965  return -1;
966  }
967 
968  do {
969  p = avpriv_mpv_find_start_code(p, buf_end, &state);
970  //av_log(s, AV_LOG_INFO, "nal %d\n", state & 0x1f);
971  } while (p < buf_end && (state & 0x1f) != 9 &&
972  (state & 0x1f) != 5 && (state & 0x1f) != 1);
973 
974  if ((state & 0x1f) != 9) { // AUD NAL
975  data = av_malloc(pkt->size+6);
976  if (!data)
977  return -1;
978  memcpy(data+6, pkt->data, pkt->size);
979  AV_WB32(data, 0x00000001);
980  data[4] = 0x09;
981  data[5] = 0xf0; // any slice type (0xe) + rbsp stop one bit
982  buf = data;
983  size = pkt->size+6;
984  }
985  } else if (st->codec->codec_id == CODEC_ID_AAC) {
986  if (pkt->size < 2)
987  return -1;
988  if ((AV_RB16(pkt->data) & 0xfff0) != 0xfff0) {
989  ADTSContext *adts = ts_st->adts;
990  int new_size, err;
991  if (!adts) {
992  av_log(s, AV_LOG_ERROR, "aac bitstream not in adts format "
993  "and extradata missing\n");
994  return -1;
995  }
996  new_size = ADTS_HEADER_SIZE+adts->pce_size+pkt->size;
997  if ((unsigned)new_size >= INT_MAX)
998  return -1;
999  data = av_malloc(new_size);
1000  if (!data)
1001  return AVERROR(ENOMEM);
1002  err = ff_adts_write_frame_header(adts, data, pkt->size,
1003  adts->pce_size);
1004  if (err < 0) {
1005  av_free(data);
1006  return err;
1007  }
1008  if (adts->pce_size) {
1009  memcpy(data+ADTS_HEADER_SIZE, adts->pce_data, adts->pce_size);
1010  adts->pce_size = 0;
1011  }
1012  memcpy(data+ADTS_HEADER_SIZE+adts->pce_size, pkt->data, pkt->size);
1013  buf = data;
1014  size = new_size;
1015  }
1016  }
1017 
1018  if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO) {
1019  // for video and subtitle, write a single pes packet
1020  mpegts_write_pes(s, st, buf, size, pts, dts, pkt->flags & AV_PKT_FLAG_KEY);
1021  av_free(data);
1022  return 0;
1023  }
1024 
1025  if (ts_st->payload_size + size > ts->pes_payload_size) {
1026  if (ts_st->payload_size) {
1027  mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
1028  ts_st->payload_pts, ts_st->payload_dts,
1029  ts_st->payload_flags & AV_PKT_FLAG_KEY);
1030  ts_st->payload_size = 0;
1031  }
1032  if (size > ts->pes_payload_size) {
1033  mpegts_write_pes(s, st, buf, size, pts, dts,
1034  pkt->flags & AV_PKT_FLAG_KEY);
1035  av_free(data);
1036  return 0;
1037  }
1038  }
1039 
1040  if (!ts_st->payload_size) {
1041  ts_st->payload_pts = pts;
1042  ts_st->payload_dts = dts;
1043  ts_st->payload_flags = pkt->flags;
1044  }
1045 
1046  memcpy(ts_st->payload + ts_st->payload_size, buf, size);
1047  ts_st->payload_size += size;
1048 
1049  av_free(data);
1050 
1051  return 0;
1052 }
1053 
1055 {
1056  MpegTSWrite *ts = s->priv_data;
1057  MpegTSWriteStream *ts_st;
1058  MpegTSService *service;
1059  AVStream *st;
1060  int i;
1061 
1062  /* flush current packets */
1063  for(i = 0; i < s->nb_streams; i++) {
1064  st = s->streams[i];
1065  ts_st = st->priv_data;
1066  if (ts_st->payload_size > 0) {
1067  mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
1068  ts_st->payload_pts, ts_st->payload_dts,
1069  ts_st->payload_flags & AV_PKT_FLAG_KEY);
1070  }
1071  av_freep(&ts_st->payload);
1072  av_freep(&ts_st->adts);
1073  }
1074  avio_flush(s->pb);
1075 
1076  for(i = 0; i < ts->nb_services; i++) {
1077  service = ts->services[i];
1078  av_freep(&service->provider_name);
1079  av_freep(&service->name);
1080  av_free(service);
1081  }
1082  av_free(ts->services);
1083 
1084  return 0;
1085 }
1086 
1088  .name = "mpegts",
1089  .long_name = NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
1090  .mime_type = "video/x-mpegts",
1091  .extensions = "ts,m2t",
1092  .priv_data_size = sizeof(MpegTSWrite),
1093  .audio_codec = CODEC_ID_MP2,
1094  .video_codec = CODEC_ID_MPEG2VIDEO,
1098  .priv_class = &mpegts_muxer_class,
1099 };