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 /* The section length is 12 bits. The first 2 are set to 0, the remaining
110  * 10 bits should not exceed 1021. */
111 #define SECTION_LENGTH 1020
112 
113 /* NOTE: 4 bytes must be left at the end for the crc32 */
114 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
115 {
116  unsigned int crc;
117  unsigned char packet[TS_PACKET_SIZE];
118  const unsigned char *buf_ptr;
119  unsigned char *q;
120  int first, b, len1, left;
121 
122  crc = av_bswap32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
123  buf[len - 4] = (crc >> 24) & 0xff;
124  buf[len - 3] = (crc >> 16) & 0xff;
125  buf[len - 2] = (crc >> 8) & 0xff;
126  buf[len - 1] = (crc) & 0xff;
127 
128  /* send each packet */
129  buf_ptr = buf;
130  while (len > 0) {
131  first = (buf == buf_ptr);
132  q = packet;
133  *q++ = 0x47;
134  b = (s->pid >> 8);
135  if (first)
136  b |= 0x40;
137  *q++ = b;
138  *q++ = s->pid;
139  s->cc = (s->cc + 1) & 0xf;
140  *q++ = 0x10 | s->cc;
141  if (first)
142  *q++ = 0; /* 0 offset */
143  len1 = TS_PACKET_SIZE - (q - packet);
144  if (len1 > len)
145  len1 = len;
146  memcpy(q, buf_ptr, len1);
147  q += len1;
148  /* add known padding data */
149  left = TS_PACKET_SIZE - (q - packet);
150  if (left > 0)
151  memset(q, 0xff, left);
152 
153  s->write_packet(s, packet);
154 
155  buf_ptr += len1;
156  len -= len1;
157  }
158 }
159 
160 static inline void put16(uint8_t **q_ptr, int val)
161 {
162  uint8_t *q;
163  q = *q_ptr;
164  *q++ = val >> 8;
165  *q++ = val;
166  *q_ptr = q;
167 }
168 
169 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
170  int version, int sec_num, int last_sec_num,
171  uint8_t *buf, int len)
172 {
173  uint8_t section[1024], *q;
174  unsigned int tot_len;
175  /* reserved_future_use field must be set to 1 for SDT */
176  unsigned int flags = tid == SDT_TID ? 0xf000 : 0xb000;
177 
178  tot_len = 3 + 5 + len + 4;
179  /* check if not too big */
180  if (tot_len > 1024)
181  return -1;
182 
183  q = section;
184  *q++ = tid;
185  put16(&q, flags | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
186  put16(&q, id);
187  *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
188  *q++ = sec_num;
189  *q++ = last_sec_num;
190  memcpy(q, buf, len);
191 
192  mpegts_write_section(s, section, tot_len);
193  return 0;
194 }
195 
196 /*********************************************/
197 /* mpegts writer */
198 
199 #define DEFAULT_PROVIDER_NAME "Libav"
200 #define DEFAULT_SERVICE_NAME "Service01"
201 
202 /* we retransmit the SI info at this rate */
203 #define SDT_RETRANS_TIME 500
204 #define PAT_RETRANS_TIME 100
205 #define PCR_RETRANS_TIME 20
206 
207 typedef struct MpegTSWriteStream {
209  int pid; /* stream associated pid */
210  int cc;
213  int64_t payload_pts;
214  int64_t payload_dts;
216  uint8_t *payload;
219 
221 {
222  MpegTSWrite *ts = s->priv_data;
223  MpegTSService *service;
224  uint8_t data[SECTION_LENGTH], *q;
225  int i;
226 
227  q = data;
228  for(i = 0; i < ts->nb_services; i++) {
229  service = ts->services[i];
230  put16(&q, service->sid);
231  put16(&q, 0xe000 | service->pmt.pid);
232  }
233  mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
234  data, q - data);
235 }
236 
238 {
239  uint8_t data[SECTION_LENGTH], *q, *desc_length_ptr, *program_info_length_ptr;
240  int val, stream_type, i, err = 0;
241 
242  q = data;
243  put16(&q, 0xe000 | service->pcr_pid);
244 
245  program_info_length_ptr = q;
246  q += 2; /* patched after */
247 
248  /* put program info here */
249 
250  val = 0xf000 | (q - program_info_length_ptr - 2);
251  program_info_length_ptr[0] = val >> 8;
252  program_info_length_ptr[1] = val;
253 
254  for(i = 0; i < s->nb_streams; i++) {
255  AVStream *st = s->streams[i];
256  MpegTSWriteStream *ts_st = st->priv_data;
257  AVDictionaryEntry *lang = av_dict_get(st->metadata, "language", NULL,0);
258 
259  if (q - data > SECTION_LENGTH - 3 - 2 - 6) {
260  err = 1;
261  break;
262  }
263  switch(st->codec->codec_id) {
264  case CODEC_ID_MPEG1VIDEO:
265  case CODEC_ID_MPEG2VIDEO:
266  stream_type = STREAM_TYPE_VIDEO_MPEG2;
267  break;
268  case CODEC_ID_MPEG4:
269  stream_type = STREAM_TYPE_VIDEO_MPEG4;
270  break;
271  case CODEC_ID_H264:
272  stream_type = STREAM_TYPE_VIDEO_H264;
273  break;
274  case CODEC_ID_DIRAC:
275  stream_type = STREAM_TYPE_VIDEO_DIRAC;
276  break;
277  case CODEC_ID_MP2:
278  case CODEC_ID_MP3:
279  stream_type = STREAM_TYPE_AUDIO_MPEG1;
280  break;
281  case CODEC_ID_AAC:
282  stream_type = STREAM_TYPE_AUDIO_AAC;
283  break;
284  case CODEC_ID_AAC_LATM:
285  stream_type = STREAM_TYPE_AUDIO_AAC_LATM;
286  break;
287  case CODEC_ID_AC3:
288  stream_type = STREAM_TYPE_AUDIO_AC3;
289  break;
290  default:
291  stream_type = STREAM_TYPE_PRIVATE_DATA;
292  break;
293  }
294  *q++ = stream_type;
295  put16(&q, 0xe000 | ts_st->pid);
296  desc_length_ptr = q;
297  q += 2; /* patched after */
298 
299  /* write optional descriptors here */
300  switch(st->codec->codec_type) {
301  case AVMEDIA_TYPE_AUDIO:
302  if (lang) {
303  char *p;
304  char *next = lang->value;
305  uint8_t *len_ptr;
306 
307  *q++ = 0x0a; /* ISO 639 language descriptor */
308  len_ptr = q++;
309  *len_ptr = 0;
310 
311  for (p = lang->value; next && *len_ptr < 255 / 4 * 4; p = next + 1) {
312  if (q - data > SECTION_LENGTH - 4) {
313  err = 1;
314  break;
315  }
316  next = strchr(p, ',');
317  if (strlen(p) != 3 && (!next || next != p + 3))
318  continue; /* not a 3-letter code */
319 
320  *q++ = *p++;
321  *q++ = *p++;
322  *q++ = *p++;
323 
325  *q++ = 0x01;
327  *q++ = 0x02;
329  *q++ = 0x03;
330  else
331  *q++ = 0; /* undefined type */
332 
333  *len_ptr += 4;
334  }
335 
336  if (*len_ptr == 0)
337  q -= 2; /* no language codes were written */
338  }
339  break;
341  {
342  const char *language;
343  language = lang && strlen(lang->value)==3 ? lang->value : "eng";
344  *q++ = 0x59;
345  *q++ = 8;
346  *q++ = language[0];
347  *q++ = language[1];
348  *q++ = language[2];
349  *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
350 
351  if (q - data > SECTION_LENGTH - 4) {
352  err = 1;
353  break;
354  }
355  if(st->codec->extradata_size == 4) {
356  memcpy(q, st->codec->extradata, 4);
357  q += 4;
358  } else {
359  put16(&q, 1); /* page id */
360  put16(&q, 1); /* ancillary page id */
361  }
362  }
363  break;
364  case AVMEDIA_TYPE_VIDEO:
365  if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
366  *q++ = 0x05; /*MPEG-2 registration descriptor*/
367  *q++ = 4;
368  *q++ = 'd';
369  *q++ = 'r';
370  *q++ = 'a';
371  *q++ = 'c';
372  }
373  break;
374  }
375 
376  val = 0xf000 | (q - desc_length_ptr - 2);
377  desc_length_ptr[0] = val >> 8;
378  desc_length_ptr[1] = val;
379  }
380 
381  if (err)
382  av_log(s, AV_LOG_ERROR,
383  "The PMT section is too small for stream %d and following.\n"
384  "Try reducing the number of languages in the audio streams "
385  "or the total number of streams.\n",
386  i);
387 
388  mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
389  data, q - data);
390 }
391 
392 /* NOTE: str == NULL is accepted for an empty string */
393 static void putstr8(uint8_t **q_ptr, const char *str)
394 {
395  uint8_t *q;
396  int len;
397 
398  q = *q_ptr;
399  if (!str)
400  len = 0;
401  else
402  len = strlen(str);
403  *q++ = len;
404  memcpy(q, str, len);
405  q += len;
406  *q_ptr = q;
407 }
408 
410 {
411  MpegTSWrite *ts = s->priv_data;
412  MpegTSService *service;
413  uint8_t data[SECTION_LENGTH], *q, *desc_list_len_ptr, *desc_len_ptr;
414  int i, running_status, free_ca_mode, val;
415 
416  q = data;
417  put16(&q, ts->onid);
418  *q++ = 0xff;
419  for(i = 0; i < ts->nb_services; i++) {
420  service = ts->services[i];
421  put16(&q, service->sid);
422  *q++ = 0xfc | 0x00; /* currently no EIT info */
423  desc_list_len_ptr = q;
424  q += 2;
425  running_status = 4; /* running */
426  free_ca_mode = 0;
427 
428  /* write only one descriptor for the service name and provider */
429  *q++ = 0x48;
430  desc_len_ptr = q;
431  q++;
432  *q++ = 0x01; /* digital television service */
433  putstr8(&q, service->provider_name);
434  putstr8(&q, service->name);
435  desc_len_ptr[0] = q - desc_len_ptr - 1;
436 
437  /* fill descriptor length */
438  val = (running_status << 13) | (free_ca_mode << 12) |
439  (q - desc_list_len_ptr - 2);
440  desc_list_len_ptr[0] = val >> 8;
441  desc_list_len_ptr[1] = val;
442  }
443  mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
444  data, q - data);
445 }
446 
448  int sid,
449  const char *provider_name,
450  const char *name)
451 {
452  MpegTSService *service;
453 
454  service = av_mallocz(sizeof(MpegTSService));
455  if (!service)
456  return NULL;
457  service->pmt.pid = ts->pmt_start_pid + ts->nb_services;
458  service->sid = sid;
459  service->provider_name = av_strdup(provider_name);
460  service->name = av_strdup(name);
461  service->pcr_pid = 0x1fff;
462  dynarray_add(&ts->services, &ts->nb_services, service);
463  return service;
464 }
465 
466 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
467 {
468  AVFormatContext *ctx = s->opaque;
469  avio_write(ctx->pb, packet, TS_PACKET_SIZE);
470 }
471 
473 {
474  MpegTSWrite *ts = s->priv_data;
475  MpegTSWriteStream *ts_st;
476  MpegTSService *service;
477  AVStream *st, *pcr_st = NULL;
478  AVDictionaryEntry *title, *provider;
479  int i, j;
480  const char *service_name;
481  const char *provider_name;
482  int *pids;
483 
484  // round up to a whole number of TS packets
485  ts->pes_payload_size = (ts->pes_payload_size + 14 + 183) / 184 * 184 - 14;
486 
487  ts->tsid = ts->transport_stream_id;
488  ts->onid = ts->original_network_id;
489  /* allocate a single DVB service */
490  title = av_dict_get(s->metadata, "service_name", NULL, 0);
491  if (!title)
492  title = av_dict_get(s->metadata, "title", NULL, 0);
493  service_name = title ? title->value : DEFAULT_SERVICE_NAME;
494  provider = av_dict_get(s->metadata, "service_provider", NULL, 0);
495  provider_name = provider ? provider->value : DEFAULT_PROVIDER_NAME;
496  service = mpegts_add_service(ts, ts->service_id, provider_name, service_name);
498  service->pmt.opaque = s;
499  service->pmt.cc = 15;
500 
501  ts->pat.pid = PAT_PID;
502  ts->pat.cc = 15; // Initialize at 15 so that it wraps and be equal to 0 for the first packet we write
504  ts->pat.opaque = s;
505 
506  ts->sdt.pid = SDT_PID;
507  ts->sdt.cc = 15;
509  ts->sdt.opaque = s;
510 
511  pids = av_malloc(s->nb_streams * sizeof(*pids));
512  if (!pids)
513  return AVERROR(ENOMEM);
514 
515  /* assign pids to each stream */
516  for(i = 0;i < s->nb_streams; i++) {
517  st = s->streams[i];
518  avpriv_set_pts_info(st, 33, 1, 90000);
519  ts_st = av_mallocz(sizeof(MpegTSWriteStream));
520  if (!ts_st)
521  goto fail;
522  st->priv_data = ts_st;
523  ts_st->payload = av_mallocz(ts->pes_payload_size);
524  if (!ts_st->payload)
525  goto fail;
526  ts_st->service = service;
527  /* MPEG pid values < 16 are reserved. Applications which set st->id in
528  * this range are assigned a calculated pid. */
529  if (st->id < 16) {
530  ts_st->pid = ts->start_pid + i;
531  } else if (st->id < 0x1FFF) {
532  ts_st->pid = st->id;
533  } else {
534  av_log(s, AV_LOG_ERROR, "Invalid stream id %d, must be less than 8191\n", st->id);
535  goto fail;
536  }
537  if (ts_st->pid == service->pmt.pid) {
538  av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
539  goto fail;
540  }
541  for (j = 0; j < i; j++)
542  if (pids[j] == ts_st->pid) {
543  av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
544  goto fail;
545  }
546  pids[i] = ts_st->pid;
547  ts_st->payload_pts = AV_NOPTS_VALUE;
548  ts_st->payload_dts = AV_NOPTS_VALUE;
549  ts_st->first_pts_check = 1;
550  ts_st->cc = 15;
551  /* update PCR pid by using the first video stream */
552  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
553  service->pcr_pid == 0x1fff) {
554  service->pcr_pid = ts_st->pid;
555  pcr_st = st;
556  }
557  if (st->codec->codec_id == CODEC_ID_AAC &&
558  st->codec->extradata_size > 0) {
559  ts_st->adts = av_mallocz(sizeof(*ts_st->adts));
560  if (!ts_st->adts)
561  goto fail;
562  if (ff_adts_decode_extradata(s, ts_st->adts, st->codec->extradata,
563  st->codec->extradata_size) < 0)
564  goto fail;
565  }
566  }
567 
568  av_free(pids);
569 
570  /* if no video stream, use the first stream as PCR */
571  if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
572  pcr_st = s->streams[0];
573  ts_st = pcr_st->priv_data;
574  service->pcr_pid = ts_st->pid;
575  }
576 
577 #if FF_API_MUXRATE
578  if (s->mux_rate)
579  ts->mux_rate = s->mux_rate;
580 #endif
581 
582  if (ts->mux_rate > 1) {
583  service->pcr_packet_period = (ts->mux_rate * PCR_RETRANS_TIME) /
584  (TS_PACKET_SIZE * 8 * 1000);
586  (TS_PACKET_SIZE * 8 * 1000);
588  (TS_PACKET_SIZE * 8 * 1000);
589 
591  } else {
592  /* Arbitrary values, PAT/PMT could be written on key frames */
593  ts->sdt_packet_period = 200;
594  ts->pat_packet_period = 40;
595  if (pcr_st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
596  if (!pcr_st->codec->frame_size) {
597  av_log(s, AV_LOG_WARNING, "frame size not set\n");
598  service->pcr_packet_period =
599  pcr_st->codec->sample_rate/(10*512);
600  } else {
601  service->pcr_packet_period =
602  pcr_st->codec->sample_rate/(10*pcr_st->codec->frame_size);
603  }
604  } else {
605  // max delta PCR 0.1s
606  service->pcr_packet_period =
607  pcr_st->codec->time_base.den/(10*pcr_st->codec->time_base.num);
608  }
609  }
610 
611  // output a PCR as soon as possible
612  service->pcr_packet_count = service->pcr_packet_period;
615 
616  if (ts->mux_rate == 1)
617  av_log(s, AV_LOG_INFO, "muxrate VBR, ");
618  else
619  av_log(s, AV_LOG_INFO, "muxrate %d, ", ts->mux_rate);
620  av_log(s, AV_LOG_INFO, "pcr every %d pkts, "
621  "sdt every %d, pat/pmt every %d pkts\n",
622  service->pcr_packet_period,
624 
625  avio_flush(s->pb);
626 
627  return 0;
628 
629  fail:
630  av_free(pids);
631  for(i = 0;i < s->nb_streams; i++) {
632  MpegTSWriteStream *ts_st;
633  st = s->streams[i];
634  ts_st = st->priv_data;
635  if (ts_st) {
636  av_freep(&ts_st->payload);
637  av_freep(&ts_st->adts);
638  }
639  av_freep(&st->priv_data);
640  }
641  return -1;
642 }
643 
644 /* send SDT, PAT and PMT tables regulary */
646 {
647  MpegTSWrite *ts = s->priv_data;
648  int i;
649 
650  if (++ts->sdt_packet_count == ts->sdt_packet_period) {
651  ts->sdt_packet_count = 0;
652  mpegts_write_sdt(s);
653  }
654  if (++ts->pat_packet_count == ts->pat_packet_period) {
655  ts->pat_packet_count = 0;
656  mpegts_write_pat(s);
657  for(i = 0; i < ts->nb_services; i++) {
658  mpegts_write_pmt(s, ts->services[i]);
659  }
660  }
661 }
662 
663 static int64_t get_pcr(const MpegTSWrite *ts, AVIOContext *pb)
664 {
665  return av_rescale(avio_tell(pb) + 11, 8 * PCR_TIME_BASE, ts->mux_rate) +
666  ts->first_pcr;
667 }
668 
669 static int write_pcr_bits(uint8_t *buf, int64_t pcr)
670 {
671  int64_t pcr_low = pcr % 300, pcr_high = pcr / 300;
672 
673  *buf++ = pcr_high >> 25;
674  *buf++ = pcr_high >> 17;
675  *buf++ = pcr_high >> 9;
676  *buf++ = pcr_high >> 1;
677  *buf++ = pcr_high << 7 | pcr_low >> 8 | 0x7e;
678  *buf++ = pcr_low;
679 
680  return 6;
681 }
682 
683 /* Write a single null transport stream packet */
685 {
686  uint8_t *q;
687  uint8_t buf[TS_PACKET_SIZE];
688 
689  q = buf;
690  *q++ = 0x47;
691  *q++ = 0x00 | 0x1f;
692  *q++ = 0xff;
693  *q++ = 0x10;
694  memset(q, 0x0FF, TS_PACKET_SIZE - (q - buf));
695  avio_write(s->pb, buf, TS_PACKET_SIZE);
696 }
697 
698 /* Write a single transport stream packet with a PCR and no payload */
700 {
701  MpegTSWrite *ts = s->priv_data;
702  MpegTSWriteStream *ts_st = st->priv_data;
703  uint8_t *q;
704  uint8_t buf[TS_PACKET_SIZE];
705 
706  q = buf;
707  *q++ = 0x47;
708  *q++ = ts_st->pid >> 8;
709  *q++ = ts_st->pid;
710  *q++ = 0x20 | ts_st->cc; /* Adaptation only */
711  /* Continuity Count field does not increment (see 13818-1 section 2.4.3.3) */
712  *q++ = TS_PACKET_SIZE - 5; /* Adaptation Field Length */
713  *q++ = 0x10; /* Adaptation flags: PCR present */
714 
715  /* PCR coded into 6 bytes */
716  q += write_pcr_bits(q, get_pcr(ts, s->pb));
717 
718  /* stuffing bytes */
719  memset(q, 0xFF, TS_PACKET_SIZE - (q - buf));
720  avio_write(s->pb, buf, TS_PACKET_SIZE);
721 }
722 
723 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
724 {
725  int val;
726 
727  val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
728  *q++ = val;
729  val = (((pts >> 15) & 0x7fff) << 1) | 1;
730  *q++ = val >> 8;
731  *q++ = val;
732  val = (((pts) & 0x7fff) << 1) | 1;
733  *q++ = val >> 8;
734  *q++ = val;
735 }
736 
737 /* Set an adaptation field flag in an MPEG-TS packet*/
738 static void set_af_flag(uint8_t *pkt, int flag)
739 {
740  // expect at least one flag to set
741  assert(flag);
742 
743  if ((pkt[3] & 0x20) == 0) {
744  // no AF yet, set adaptation field flag
745  pkt[3] |= 0x20;
746  // 1 byte length, no flags
747  pkt[4] = 1;
748  pkt[5] = 0;
749  }
750  pkt[5] |= flag;
751 }
752 
753 /* Extend the adaptation field by size bytes */
754 static void extend_af(uint8_t *pkt, int size)
755 {
756  // expect already existing adaptation field
757  assert(pkt[3] & 0x20);
758  pkt[4] += size;
759 }
760 
761 /* Get a pointer to MPEG-TS payload (right after TS packet header) */
762 static uint8_t *get_ts_payload_start(uint8_t *pkt)
763 {
764  if (pkt[3] & 0x20)
765  return pkt + 5 + pkt[4];
766  else
767  return pkt + 4;
768 }
769 
770 /* Add a pes header to the front of payload, and segment into an integer number of
771  * ts packets. The final ts packet is padded using an over-sized adaptation header
772  * to exactly fill the last ts packet.
773  * NOTE: 'payload' contains a complete PES payload.
774  */
776  const uint8_t *payload, int payload_size,
777  int64_t pts, int64_t dts, int key)
778 {
779  MpegTSWriteStream *ts_st = st->priv_data;
780  MpegTSWrite *ts = s->priv_data;
781  uint8_t buf[TS_PACKET_SIZE];
782  uint8_t *q;
783  int val, is_start, len, header_len, write_pcr, private_code, flags;
784  int afc_len, stuffing_len;
785  int64_t pcr = -1; /* avoid warning */
786  int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);
787 
788  is_start = 1;
789  while (payload_size > 0) {
791 
792  write_pcr = 0;
793  if (ts_st->pid == ts_st->service->pcr_pid) {
794  if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on frames
795  ts_st->service->pcr_packet_count++;
796  if (ts_st->service->pcr_packet_count >=
797  ts_st->service->pcr_packet_period) {
798  ts_st->service->pcr_packet_count = 0;
799  write_pcr = 1;
800  }
801  }
802 
803  if (ts->mux_rate > 1 && dts != AV_NOPTS_VALUE &&
804  (dts - get_pcr(ts, s->pb)/300) > delay) {
805  /* pcr insert gets priority over null packet insert */
806  if (write_pcr)
807  mpegts_insert_pcr_only(s, st);
808  else
810  continue; /* recalculate write_pcr and possibly retransmit si_info */
811  }
812 
813  /* prepare packet header */
814  q = buf;
815  *q++ = 0x47;
816  val = (ts_st->pid >> 8);
817  if (is_start)
818  val |= 0x40;
819  *q++ = val;
820  *q++ = ts_st->pid;
821  ts_st->cc = (ts_st->cc + 1) & 0xf;
822  *q++ = 0x10 | ts_st->cc; // payload indicator + CC
823  if (key && is_start && pts != AV_NOPTS_VALUE) {
824  // set Random Access for key frames
825  if (ts_st->pid == ts_st->service->pcr_pid)
826  write_pcr = 1;
827  set_af_flag(buf, 0x40);
828  q = get_ts_payload_start(buf);
829  }
830  if (write_pcr) {
831  set_af_flag(buf, 0x10);
832  q = get_ts_payload_start(buf);
833  // add 11, pcr references the last byte of program clock reference base
834  if (ts->mux_rate > 1)
835  pcr = get_pcr(ts, s->pb);
836  else
837  pcr = (dts - delay)*300;
838  if (dts != AV_NOPTS_VALUE && dts < pcr / 300)
839  av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");
840  extend_af(buf, write_pcr_bits(q, pcr));
841  q = get_ts_payload_start(buf);
842  }
843  if (is_start) {
844  int pes_extension = 0;
845  /* write PES header */
846  *q++ = 0x00;
847  *q++ = 0x00;
848  *q++ = 0x01;
849  private_code = 0;
850  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
851  if (st->codec->codec_id == CODEC_ID_DIRAC) {
852  *q++ = 0xfd;
853  } else
854  *q++ = 0xe0;
855  } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
856  (st->codec->codec_id == CODEC_ID_MP2 ||
857  st->codec->codec_id == CODEC_ID_MP3 ||
858  st->codec->codec_id == CODEC_ID_AAC)) {
859  *q++ = 0xc0;
860  } else {
861  *q++ = 0xbd;
862  if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
863  private_code = 0x20;
864  }
865  }
866  header_len = 0;
867  flags = 0;
868  if (pts != AV_NOPTS_VALUE) {
869  header_len += 5;
870  flags |= 0x80;
871  }
872  if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
873  header_len += 5;
874  flags |= 0x40;
875  }
876  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
877  st->codec->codec_id == CODEC_ID_DIRAC) {
878  /* set PES_extension_flag */
879  pes_extension = 1;
880  flags |= 0x01;
881 
882  /*
883  * One byte for PES2 extension flag +
884  * one byte for extension length +
885  * one byte for extension id
886  */
887  header_len += 3;
888  }
889  len = payload_size + header_len + 3;
890  if (private_code != 0)
891  len++;
892  if (len > 0xffff)
893  len = 0;
894  *q++ = len >> 8;
895  *q++ = len;
896  val = 0x80;
897  /* data alignment indicator is required for subtitle data */
899  val |= 0x04;
900  *q++ = val;
901  *q++ = flags;
902  *q++ = header_len;
903  if (pts != AV_NOPTS_VALUE) {
904  write_pts(q, flags >> 6, pts);
905  q += 5;
906  }
907  if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
908  write_pts(q, 1, dts);
909  q += 5;
910  }
911  if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {
912  flags = 0x01; /* set PES_extension_flag_2 */
913  *q++ = flags;
914  *q++ = 0x80 | 0x01; /* marker bit + extension length */
915  /*
916  * Set the stream id extension flag bit to 0 and
917  * write the extended stream id
918  */
919  *q++ = 0x00 | 0x60;
920  }
921  if (private_code != 0)
922  *q++ = private_code;
923  is_start = 0;
924  }
925  /* header size */
926  header_len = q - buf;
927  /* data len */
928  len = TS_PACKET_SIZE - header_len;
929  if (len > payload_size)
930  len = payload_size;
931  stuffing_len = TS_PACKET_SIZE - header_len - len;
932  if (stuffing_len > 0) {
933  /* add stuffing with AFC */
934  if (buf[3] & 0x20) {
935  /* stuffing already present: increase its size */
936  afc_len = buf[4] + 1;
937  memmove(buf + 4 + afc_len + stuffing_len,
938  buf + 4 + afc_len,
939  header_len - (4 + afc_len));
940  buf[4] += stuffing_len;
941  memset(buf + 4 + afc_len, 0xff, stuffing_len);
942  } else {
943  /* add stuffing */
944  memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
945  buf[3] |= 0x20;
946  buf[4] = stuffing_len - 1;
947  if (stuffing_len >= 2) {
948  buf[5] = 0x00;
949  memset(buf + 6, 0xff, stuffing_len - 2);
950  }
951  }
952  }
953  memcpy(buf + TS_PACKET_SIZE - len, payload, len);
954  payload += len;
955  payload_size -= len;
956  avio_write(s->pb, buf, TS_PACKET_SIZE);
957  }
958  avio_flush(s->pb);
959 }
960 
962 {
963  AVStream *st = s->streams[pkt->stream_index];
964  int size = pkt->size;
965  uint8_t *buf= pkt->data;
966  uint8_t *data= NULL;
967  MpegTSWrite *ts = s->priv_data;
968  MpegTSWriteStream *ts_st = st->priv_data;
969  const uint64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE)*2;
970  int64_t dts = AV_NOPTS_VALUE, pts = AV_NOPTS_VALUE;
971 
972  if (pkt->pts != AV_NOPTS_VALUE)
973  pts = pkt->pts + delay;
974  if (pkt->dts != AV_NOPTS_VALUE)
975  dts = pkt->dts + delay;
976 
977  if (ts_st->first_pts_check && pts == AV_NOPTS_VALUE) {
978  av_log(s, AV_LOG_ERROR, "first pts value must set\n");
979  return -1;
980  }
981  ts_st->first_pts_check = 0;
982 
983  if (st->codec->codec_id == CODEC_ID_H264) {
984  const uint8_t *p = buf, *buf_end = p+size;
985  uint32_t state = -1;
986 
987  if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {
988  av_log(s, AV_LOG_ERROR, "H.264 bitstream malformed, "
989  "no startcode found, use -vbsf h264_mp4toannexb\n");
990  return -1;
991  }
992 
993  do {
994  p = avpriv_mpv_find_start_code(p, buf_end, &state);
995  //av_log(s, AV_LOG_INFO, "nal %d\n", state & 0x1f);
996  } while (p < buf_end && (state & 0x1f) != 9 &&
997  (state & 0x1f) != 5 && (state & 0x1f) != 1);
998 
999  if ((state & 0x1f) != 9) { // AUD NAL
1000  data = av_malloc(pkt->size+6);
1001  if (!data)
1002  return -1;
1003  memcpy(data+6, pkt->data, pkt->size);
1004  AV_WB32(data, 0x00000001);
1005  data[4] = 0x09;
1006  data[5] = 0xf0; // any slice type (0xe) + rbsp stop one bit
1007  buf = data;
1008  size = pkt->size+6;
1009  }
1010  } else if (st->codec->codec_id == CODEC_ID_AAC) {
1011  if (pkt->size < 2)
1012  return -1;
1013  if ((AV_RB16(pkt->data) & 0xfff0) != 0xfff0) {
1014  ADTSContext *adts = ts_st->adts;
1015  int new_size, err;
1016  if (!adts) {
1017  av_log(s, AV_LOG_ERROR, "aac bitstream not in adts format "
1018  "and extradata missing\n");
1019  return -1;
1020  }
1021  new_size = ADTS_HEADER_SIZE+adts->pce_size+pkt->size;
1022  if ((unsigned)new_size >= INT_MAX)
1023  return -1;
1024  data = av_malloc(new_size);
1025  if (!data)
1026  return AVERROR(ENOMEM);
1027  err = ff_adts_write_frame_header(adts, data, pkt->size,
1028  adts->pce_size);
1029  if (err < 0) {
1030  av_free(data);
1031  return err;
1032  }
1033  if (adts->pce_size) {
1034  memcpy(data+ADTS_HEADER_SIZE, adts->pce_data, adts->pce_size);
1035  adts->pce_size = 0;
1036  }
1037  memcpy(data+ADTS_HEADER_SIZE+adts->pce_size, pkt->data, pkt->size);
1038  buf = data;
1039  size = new_size;
1040  }
1041  }
1042 
1043  if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO) {
1044  // for video and subtitle, write a single pes packet
1045  mpegts_write_pes(s, st, buf, size, pts, dts, pkt->flags & AV_PKT_FLAG_KEY);
1046  av_free(data);
1047  return 0;
1048  }
1049 
1050  if (ts_st->payload_size + size > ts->pes_payload_size) {
1051  if (ts_st->payload_size) {
1052  mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
1053  ts_st->payload_pts, ts_st->payload_dts,
1054  ts_st->payload_flags & AV_PKT_FLAG_KEY);
1055  ts_st->payload_size = 0;
1056  }
1057  if (size > ts->pes_payload_size) {
1058  mpegts_write_pes(s, st, buf, size, pts, dts,
1059  pkt->flags & AV_PKT_FLAG_KEY);
1060  av_free(data);
1061  return 0;
1062  }
1063  }
1064 
1065  if (!ts_st->payload_size) {
1066  ts_st->payload_pts = pts;
1067  ts_st->payload_dts = dts;
1068  ts_st->payload_flags = pkt->flags;
1069  }
1070 
1071  memcpy(ts_st->payload + ts_st->payload_size, buf, size);
1072  ts_st->payload_size += size;
1073 
1074  av_free(data);
1075 
1076  return 0;
1077 }
1078 
1080 {
1081  MpegTSWrite *ts = s->priv_data;
1082  MpegTSWriteStream *ts_st;
1083  MpegTSService *service;
1084  AVStream *st;
1085  int i;
1086 
1087  /* flush current packets */
1088  for(i = 0; i < s->nb_streams; i++) {
1089  st = s->streams[i];
1090  ts_st = st->priv_data;
1091  if (ts_st->payload_size > 0) {
1092  mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_size,
1093  ts_st->payload_pts, ts_st->payload_dts,
1094  ts_st->payload_flags & AV_PKT_FLAG_KEY);
1095  }
1096  av_freep(&ts_st->payload);
1097  av_freep(&ts_st->adts);
1098  }
1099  avio_flush(s->pb);
1100 
1101  for(i = 0; i < ts->nb_services; i++) {
1102  service = ts->services[i];
1103  av_freep(&service->provider_name);
1104  av_freep(&service->name);
1105  av_free(service);
1106  }
1107  av_free(ts->services);
1108 
1109  return 0;
1110 }
1111 
1113  .name = "mpegts",
1114  .long_name = NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
1115  .mime_type = "video/x-mpegts",
1116  .extensions = "ts,m2t",
1117  .priv_data_size = sizeof(MpegTSWrite),
1118  .audio_codec = CODEC_ID_MP2,
1119  .video_codec = CODEC_ID_MPEG2VIDEO,
1123  .priv_class = &mpegts_muxer_class,
1124 };