libavformat/mpegtsenc.c

   1 /*
   2  * MPEG2 transport stream (aka DVB) muxer
   3  * Copyright (c) 2003 Fabrice Bellard
   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
   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  * 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 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 FFmpeg; 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 "libavcodec/mpegvideo.h"
  25 #include "avformat.h"
  26 #include "internal.h"
  27 #include "mpegts.h"
  28 #include "adts.h"
  29
  30 /* write DVB SI sections */
  31
  32 /*********************************************/
  33 /* mpegts section writer */
  34
  35 typedef struct MpegTSSection {
  36     int pid;
  37     int cc;
  38     void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
  39     void *opaque;
  40 } MpegTSSection;
  41
  42 typedef struct MpegTSService {
  43     MpegTSSection pmt; /* MPEG2 pmt table context */
  44     int sid;           /* service ID */
  45     char *name;
  46     char *provider_name;
  47     int pcr_pid;
  48     int pcr_packet_count;
  49     int pcr_packet_period;
  50 } MpegTSService;
  51
  52 typedef struct MpegTSWrite {
  53     MpegTSSection pat; /* MPEG2 pat table */
  54     MpegTSSection sdt; /* MPEG2 sdt table context */
  55     MpegTSService **services;
  56     int sdt_packet_count;
  57     int sdt_packet_period;
  58     int pat_packet_count;
  59     int pat_packet_period;
  60     int nb_services;
  61     int onid;
  62     int tsid;
  63     uint64_t cur_pcr;
  64     int mux_rate; ///< set to 1 when VBR
  65 } MpegTSWrite;
  66
  67 /* NOTE: 4 bytes must be left at the end for the crc32 */
  68 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
  69 {
  70     MpegTSWrite *ts = ((AVFormatContext*)s->opaque)->priv_data;
  71     unsigned int crc;
  72     unsigned char packet[TS_PACKET_SIZE];
  73     const unsigned char *buf_ptr;
  74     unsigned char *q;
  75     int first, b, len1, left;
  76
  77     crc = bswap_32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
  78     buf[len - 4] = (crc >> 24) & 0xff;
  79     buf[len - 3] = (crc >> 16) & 0xff;
  80     buf[len - 2] = (crc >> 8) & 0xff;
  81     buf[len - 1] = (crc) & 0xff;
  82
  83     /* send each packet */
  84     buf_ptr = buf;
  85     while (len > 0) {
  86         first = (buf == buf_ptr);
  87         q = packet;
  88         *q++ = 0x47;
  89         b = (s->pid >> 8);
  90         if (first)
  91             b |= 0x40;
  92         *q++ = b;
  93         *q++ = s->pid;
  94         s->cc = (s->cc + 1) & 0xf;
  95         *q++ = 0x10 | s->cc;
  96         if (first)
  97             *q++ = 0; /* 0 offset */
  98         len1 = TS_PACKET_SIZE - (q - packet);
  99         if (len1 > len)
 100             len1 = len;
 101         memcpy(q, buf_ptr, len1);
 102         q += len1;
 103         /* add known padding data */
 104         left = TS_PACKET_SIZE - (q - packet);
 105         if (left > 0)
 106             memset(q, 0xff, left);
 107
 108         s->write_packet(s, packet);
 109
 110         buf_ptr += len1;
 111         len -= len1;
 112
 113         ts->cur_pcr += TS_PACKET_SIZE*8*90000LL/ts->mux_rate;
 114     }
 115 }
 116
 117 static inline void put16(uint8_t **q_ptr, int val)
 118 {
 119     uint8_t *q;
 120     q = *q_ptr;
 121     *q++ = val >> 8;
 122     *q++ = val;
 123     *q_ptr = q;
 124 }
 125
 126 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
 127                           int version, int sec_num, int last_sec_num,
 128                           uint8_t *buf, int len)
 129 {
 130     uint8_t section[1024], *q;
 131     unsigned int tot_len;
 132
 133     tot_len = 3 + 5 + len + 4;
 134     /* check if not too big */
 135     if (tot_len > 1024)
 136         return -1;
 137
 138     q = section;
 139     *q++ = tid;
 140     put16(&q, 0xb000 | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
 141     put16(&q, id);
 142     *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
 143     *q++ = sec_num;
 144     *q++ = last_sec_num;
 145     memcpy(q, buf, len);
 146
 147     mpegts_write_section(s, section, tot_len);
 148     return 0;
 149 }
 150
 151 /*********************************************/
 152 /* mpegts writer */
 153
 154 #define DEFAULT_PMT_START_PID   0x1000
 155 #define DEFAULT_START_PID       0x0100
 156 #define DEFAULT_PROVIDER_NAME   "FFmpeg"
 157 #define DEFAULT_SERVICE_NAME    "Service01"
 158
 159 /* default network id, transport stream and service identifiers */
 160 #define DEFAULT_ONID            0x0001
 161 #define DEFAULT_TSID            0x0001
 162 #define DEFAULT_SID             0x0001
 163
 164 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
 165 #define DEFAULT_PES_HEADER_FREQ 16
 166 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
 167
 168 /* we retransmit the SI info at this rate */
 169 #define SDT_RETRANS_TIME 500
 170 #define PAT_RETRANS_TIME 100
 171 #define PCR_RETRANS_TIME 20
 172
 173 typedef struct MpegTSWriteStream {
 174     struct MpegTSService *service;
 175     int pid; /* stream associated pid */
 176     int cc;
 177     int payload_index;
 178     int first_pts_check; ///< first pts check needed
 179     int64_t payload_pts;
 180     int64_t payload_dts;
 181     uint8_t payload[DEFAULT_PES_PAYLOAD_SIZE];
 182     ADTSContext *adts;
 183 } MpegTSWriteStream;
 184
 185 static void mpegts_write_pat(AVFormatContext *s)
 186 {
 187     MpegTSWrite *ts = s->priv_data;
 188     MpegTSService *service;
 189     uint8_t data[1012], *q;
 190     int i;
 191
 192     q = data;
 193     for(i = 0; i < ts->nb_services; i++) {
 194         service = ts->services[i];
 195         put16(&q, service->sid);
 196         put16(&q, 0xe000 | service->pmt.pid);
 197     }
 198     mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
 199                           data, q - data);
 200 }
 201
 202 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
 203 {
 204     //    MpegTSWrite *ts = s->priv_data;
 205     uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
 206     int val, stream_type, i;
 207
 208     q = data;
 209     put16(&q, 0xe000 | service->pcr_pid);
 210
 211     program_info_length_ptr = q;
 212     q += 2; /* patched after */
 213
 214     /* put program info here */
 215
 216     val = 0xf000 | (q - program_info_length_ptr - 2);
 217     program_info_length_ptr[0] = val >> 8;
 218     program_info_length_ptr[1] = val;
 219
 220     for(i = 0; i < s->nb_streams; i++) {
 221         AVStream *st = s->streams[i];
 222         MpegTSWriteStream *ts_st = st->priv_data;
 223         AVMetadataTag *lang = av_metadata_get(st->metadata, "language", NULL,0);
 224         switch(st->codec->codec_id) {
 225         case CODEC_ID_MPEG1VIDEO:
 226         case CODEC_ID_MPEG2VIDEO:
 227             stream_type = STREAM_TYPE_VIDEO_MPEG2;
 228             break;
 229         case CODEC_ID_MPEG4:
 230             stream_type = STREAM_TYPE_VIDEO_MPEG4;
 231             break;
 232         case CODEC_ID_H264:
 233             stream_type = STREAM_TYPE_VIDEO_H264;
 234             break;
 235         case CODEC_ID_DIRAC:
 236             stream_type = STREAM_TYPE_VIDEO_DIRAC;
 237             break;
 238         case CODEC_ID_MP2:
 239         case CODEC_ID_MP3:
 240             stream_type = STREAM_TYPE_AUDIO_MPEG1;
 241             break;
 242         case CODEC_ID_AAC:
 243             stream_type = STREAM_TYPE_AUDIO_AAC;
 244             break;
 245         case CODEC_ID_AC3:
 246             stream_type = STREAM_TYPE_AUDIO_AC3;
 247             break;
 248         default:
 249             stream_type = STREAM_TYPE_PRIVATE_DATA;
 250             break;
 251         }
 252         *q++ = stream_type;
 253         put16(&q, 0xe000 | ts_st->pid);
 254         desc_length_ptr = q;
 255         q += 2; /* patched after */
 256
 257         /* write optional descriptors here */
 258         switch(st->codec->codec_type) {
 259         case AVMEDIA_TYPE_AUDIO:
 260             if (lang && strlen(lang->value) == 3) {
 261                 *q++ = 0x0a; /* ISO 639 language descriptor */
 262                 *q++ = 4;
 263                 *q++ = lang->value[0];
 264                 *q++ = lang->value[1];
 265                 *q++ = lang->value[2];
 266                 *q++ = 0; /* undefined type */
 267             }
 268             break;
 269         case AVMEDIA_TYPE_SUBTITLE:
 270             {
 271                 const char *language;
 272                 language = lang && strlen(lang->value)==3 ? lang->value : "eng";
 273                 *q++ = 0x59;
 274                 *q++ = 8;
 275                 *q++ = language[0];
 276                 *q++ = language[1];
 277                 *q++ = language[2];
 278                 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
 279                 put16(&q, 1); /* page id */
 280                 put16(&q, 1); /* ancillary page id */
 281             }
 282             break;
 283         case AVMEDIA_TYPE_VIDEO:
 284             if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
 285                 *q++ = 0x05; /*MPEG-2 registration descriptor*/
 286                 *q++ = 4;
 287                 *q++ = 'd';
 288                 *q++ = 'r';
 289                 *q++ = 'a';
 290                 *q++ = 'c';
 291             }
 292             break;
 293         }
 294
 295         val = 0xf000 | (q - desc_length_ptr - 2);
 296         desc_length_ptr[0] = val >> 8;
 297         desc_length_ptr[1] = val;
 298     }
 299     mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
 300                           data, q - data);
 301 }
 302
 303 /* NOTE: str == NULL is accepted for an empty string */
 304 static void putstr8(uint8_t **q_ptr, const char *str)
 305 {
 306     uint8_t *q;
 307     int len;
 308
 309     q = *q_ptr;
 310     if (!str)
 311         len = 0;
 312     else
 313         len = strlen(str);
 314     *q++ = len;
 315     memcpy(q, str, len);
 316     q += len;
 317     *q_ptr = q;
 318 }
 319
 320 static void mpegts_write_sdt(AVFormatContext *s)
 321 {
 322     MpegTSWrite *ts = s->priv_data;
 323     MpegTSService *service;
 324     uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
 325     int i, running_status, free_ca_mode, val;
 326
 327     q = data;
 328     put16(&q, ts->onid);
 329     *q++ = 0xff;
 330     for(i = 0; i < ts->nb_services; i++) {
 331         service = ts->services[i];
 332         put16(&q, service->sid);
 333         *q++ = 0xfc | 0x00; /* currently no EIT info */
 334         desc_list_len_ptr = q;
 335         q += 2;
 336         running_status = 4; /* running */
 337         free_ca_mode = 0;
 338
 339         /* write only one descriptor for the service name and provider */
 340         *q++ = 0x48;
 341         desc_len_ptr = q;
 342         q++;
 343         *q++ = 0x01; /* digital television service */
 344         putstr8(&q, service->provider_name);
 345         putstr8(&q, service->name);
 346         desc_len_ptr[0] = q - desc_len_ptr - 1;
 347
 348         /* fill descriptor length */
 349         val = (running_status << 13) | (free_ca_mode << 12) |
 350             (q - desc_list_len_ptr - 2);
 351         desc_list_len_ptr[0] = val >> 8;
 352         desc_list_len_ptr[1] = val;
 353     }
 354     mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
 355                           data, q - data);
 356 }
 357
 358 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
 359                                          int sid,
 360                                          const char *provider_name,
 361                                          const char *name)
 362 {
 363     MpegTSService *service;
 364
 365     service = av_mallocz(sizeof(MpegTSService));
 366     if (!service)
 367         return NULL;
 368     service->pmt.pid = DEFAULT_PMT_START_PID + ts->nb_services - 1;
 369     service->sid = sid;
 370     service->provider_name = av_strdup(provider_name);
 371     service->name = av_strdup(name);
 372     service->pcr_pid = 0x1fff;
 373     dynarray_add(&ts->services, &ts->nb_services, service);
 374     return service;
 375 }
 376
 377 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
 378 {
 379     AVFormatContext *ctx = s->opaque;
 380     put_buffer(ctx->pb, packet, TS_PACKET_SIZE);
 381 }
 382
 383 static int mpegts_write_header(AVFormatContext *s)
 384 {
 385     MpegTSWrite *ts = s->priv_data;
 386     MpegTSWriteStream *ts_st;
 387     MpegTSService *service;
 388     AVStream *st, *pcr_st = NULL;
 389     AVMetadataTag *title;
 390     int i;
 391     const char *service_name;
 392
 393     ts->tsid = DEFAULT_TSID;
 394     ts->onid = DEFAULT_ONID;
 395     /* allocate a single DVB service */
 396     title = av_metadata_get(s->metadata, "title", NULL, 0);
 397     service_name = title ? title->value : DEFAULT_SERVICE_NAME;
 398     service = mpegts_add_service(ts, DEFAULT_SID,
 399                                  DEFAULT_PROVIDER_NAME, service_name);
 400     service->pmt.write_packet = section_write_packet;
 401     service->pmt.opaque = s;
 402     service->pmt.cc = 15;
 403
 404     ts->pat.pid = PAT_PID;
 405     ts->pat.cc = 15; // Initialize at 15 so that it wraps and be equal to 0 for the first packet we write
 406     ts->pat.write_packet = section_write_packet;
 407     ts->pat.opaque = s;
 408
 409     ts->sdt.pid = SDT_PID;
 410     ts->sdt.cc = 15;
 411     ts->sdt.write_packet = section_write_packet;
 412     ts->sdt.opaque = s;
 413
 414     /* assign pids to each stream */
 415     for(i = 0;i < s->nb_streams; i++) {
 416         st = s->streams[i];
 417         ts_st = av_mallocz(sizeof(MpegTSWriteStream));
 418         if (!ts_st)
 419             goto fail;
 420         st->priv_data = ts_st;
 421         ts_st->service = service;
 422         ts_st->pid = DEFAULT_START_PID + i;
 423         ts_st->payload_pts = AV_NOPTS_VALUE;
 424         ts_st->payload_dts = AV_NOPTS_VALUE;
 425         ts_st->first_pts_check = 1;
 426         ts_st->cc = 15;
 427         /* update PCR pid by using the first video stream */
 428         if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
 429             service->pcr_pid == 0x1fff) {
 430             service->pcr_pid = ts_st->pid;
 431             pcr_st = st;
 432         }
 433         if (st->codec->codec_id == CODEC_ID_AAC &&
 434             st->codec->extradata_size > 0) {
 435             ts_st->adts = av_mallocz(sizeof(*ts_st->adts));
 436             if (!ts_st->adts)
 437                 return AVERROR(ENOMEM);
 438             if (ff_adts_decode_extradata(s, ts_st->adts, st->codec->extradata,
 439                                          st->codec->extradata_size) < 0)
 440                 return -1;
 441         }
 442     }
 443
 444     /* if no video stream, use the first stream as PCR */
 445     if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
 446         pcr_st = s->streams[0];
 447         ts_st = pcr_st->priv_data;
 448         service->pcr_pid = ts_st->pid;
 449     }
 450
 451     ts->mux_rate = s->mux_rate ? s->mux_rate : 1;
 452
 453     if (ts->mux_rate > 1) {
 454         service->pcr_packet_period = (ts->mux_rate * PCR_RETRANS_TIME) /
 455             (TS_PACKET_SIZE * 8 * 1000);
 456         ts->sdt_packet_period      = (ts->mux_rate * SDT_RETRANS_TIME) /
 457             (TS_PACKET_SIZE * 8 * 1000);
 458         ts->pat_packet_period      = (ts->mux_rate * PAT_RETRANS_TIME) /
 459             (TS_PACKET_SIZE * 8 * 1000);
 460
 461         ts->cur_pcr = av_rescale(s->max_delay, 90000, AV_TIME_BASE);
 462     } else {
 463         /* Arbitrary values, PAT/PMT could be written on key frames */
 464         ts->sdt_packet_period = 200;
 465         ts->pat_packet_period = 40;
 466         if (pcr_st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
 467             if (!pcr_st->codec->frame_size) {
 468                 av_log(s, AV_LOG_WARNING, "frame size not set\n");
 469                 service->pcr_packet_period =
 470                     pcr_st->codec->sample_rate/(10*512);
 471             } else {
 472                 service->pcr_packet_period =
 473                     pcr_st->codec->sample_rate/(10*pcr_st->codec->frame_size);
 474             }
 475         } else {
 476             // max delta PCR 0.1s
 477             service->pcr_packet_period =
 478                 pcr_st->codec->time_base.den/(10*pcr_st->codec->time_base.num);
 479         }
 480     }
 481
 482     // output a PCR as soon as possible
 483     service->pcr_packet_count = service->pcr_packet_period;
 484     ts->pat_packet_count = ts->pat_packet_period-1;
 485     ts->sdt_packet_count = ts->sdt_packet_period-1;
 486
 487     av_log(s, AV_LOG_INFO,
 488            "muxrate %d bps, pcr every %d pkts, "
 489            "sdt every %d, pat/pmt every %d pkts\n",
 490            ts->mux_rate, service->pcr_packet_period,
 491            ts->sdt_packet_period, ts->pat_packet_period);
 492
 493
 494     put_flush_packet(s->pb);
 495
 496     return 0;
 497
 498  fail:
 499     for(i = 0;i < s->nb_streams; i++) {
 500         st = s->streams[i];
 501         av_free(st->priv_data);
 502     }
 503     return -1;
 504 }
 505
 506 /* send SDT, PAT and PMT tables regulary */
 507 static void retransmit_si_info(AVFormatContext *s)
 508 {
 509     MpegTSWrite *ts = s->priv_data;
 510     int i;
 511
 512     if (++ts->sdt_packet_count == ts->sdt_packet_period) {
 513         ts->sdt_packet_count = 0;
 514         mpegts_write_sdt(s);
 515     }
 516     if (++ts->pat_packet_count == ts->pat_packet_period) {
 517         ts->pat_packet_count = 0;
 518         mpegts_write_pat(s);
 519         for(i = 0; i < ts->nb_services; i++) {
 520             mpegts_write_pmt(s, ts->services[i]);
 521         }
 522     }
 523 }
 524
 525 /* Write a single null transport stream packet */
 526 static void mpegts_insert_null_packet(AVFormatContext *s)
 527 {
 528     MpegTSWrite *ts = s->priv_data;
 529     uint8_t *q;
 530     uint8_t buf[TS_PACKET_SIZE];
 531
 532     q = buf;
 533     *q++ = 0x47;
 534     *q++ = 0x00 | 0x1f;
 535     *q++ = 0xff;
 536     *q++ = 0x10;
 537     memset(q, 0x0FF, TS_PACKET_SIZE - (q - buf));
 538     put_buffer(s->pb, buf, TS_PACKET_SIZE);
 539     ts->cur_pcr += TS_PACKET_SIZE*8*90000LL/ts->mux_rate;
 540 }
 541
 542 /* Write a single transport stream packet with a PCR and no payload */
 543 static void mpegts_insert_pcr_only(AVFormatContext *s, AVStream *st)
 544 {
 545     MpegTSWrite *ts = s->priv_data;
 546     MpegTSWriteStream *ts_st = st->priv_data;
 547     uint8_t *q;
 548     uint64_t pcr = ts->cur_pcr;
 549     uint8_t buf[TS_PACKET_SIZE];
 550
 551     q = buf;
 552     *q++ = 0x47;
 553     *q++ = ts_st->pid >> 8;
 554     *q++ = ts_st->pid;
 555     *q++ = 0x20 | ts_st->cc;   /* Adaptation only */
 556     /* Continuity Count field does not increment (see 13818-1 section 2.4.3.3) */
 557     *q++ = TS_PACKET_SIZE - 5; /* Adaptation Field Length */
 558     *q++ = 0x10;               /* Adaptation flags: PCR present */
 559
 560     /* PCR coded into 6 bytes */
 561     *q++ = pcr >> 25;
 562     *q++ = pcr >> 17;
 563     *q++ = pcr >> 9;
 564     *q++ = pcr >> 1;
 565     *q++ = (pcr & 1) << 7;
 566     *q++ = 0;
 567
 568     /* stuffing bytes */
 569     memset(q, 0xFF, TS_PACKET_SIZE - (q - buf));
 570     put_buffer(s->pb, buf, TS_PACKET_SIZE);
 571     ts->cur_pcr += TS_PACKET_SIZE*8*90000LL/ts->mux_rate;
 572 }
 573
 574 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
 575 {
 576     int val;
 577
 578     val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
 579     *q++ = val;
 580     val = (((pts >> 15) & 0x7fff) << 1) | 1;
 581     *q++ = val >> 8;
 582     *q++ = val;
 583     val = (((pts) & 0x7fff) << 1) | 1;
 584     *q++ = val >> 8;
 585     *q++ = val;
 586 }
 587
 588 /* Add a pes header to the front of payload, and segment into an integer number of
 589  * ts packets. The final ts packet is padded using an over-sized adaptation header
 590  * to exactly fill the last ts packet.
 591  * NOTE: 'payload' contains a complete PES payload.
 592  */
 593 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
 594                              const uint8_t *payload, int payload_size,
 595                              int64_t pts, int64_t dts)
 596 {
 597     MpegTSWriteStream *ts_st = st->priv_data;
 598     MpegTSWrite *ts = s->priv_data;
 599     uint8_t buf[TS_PACKET_SIZE];
 600     uint8_t *q;
 601     int val, is_start, len, header_len, write_pcr, private_code, flags;
 602     int afc_len, stuffing_len;
 603     int64_t pcr = -1; /* avoid warning */
 604     int64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE);
 605
 606     is_start = 1;
 607     while (payload_size > 0) {
 608         retransmit_si_info(s);
 609
 610         write_pcr = 0;
 611         if (ts_st->pid == ts_st->service->pcr_pid) {
 612             if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on frames
 613                 ts_st->service->pcr_packet_count++;
 614             if (ts_st->service->pcr_packet_count >=
 615                 ts_st->service->pcr_packet_period) {
 616                 ts_st->service->pcr_packet_count = 0;
 617                 write_pcr = 1;
 618             }
 619         }
 620
 621         if (ts->mux_rate > 1 && dts != AV_NOPTS_VALUE &&
 622             (dts - (int64_t)ts->cur_pcr) > delay) {
 623             /* pcr insert gets priority over null packet insert */
 624             if (write_pcr)
 625                 mpegts_insert_pcr_only(s, st);
 626             else
 627                 mpegts_insert_null_packet(s);
 628             continue; /* recalculate write_pcr and possibly retransmit si_info */
 629         }
 630
 631         /* prepare packet header */
 632         q = buf;
 633         *q++ = 0x47;
 634         val = (ts_st->pid >> 8);
 635         if (is_start)
 636             val |= 0x40;
 637         *q++ = val;
 638         *q++ = ts_st->pid;
 639         ts_st->cc = (ts_st->cc + 1) & 0xf;
 640         *q++ = 0x10 | ts_st->cc | (write_pcr ? 0x20 : 0);
 641         if (write_pcr) {
 642             // add 11, pcr references the last byte of program clock reference base
 643             if (ts->mux_rate > 1)
 644                 pcr = ts->cur_pcr + (4+7)*8*90000LL / ts->mux_rate;
 645             else
 646                 pcr = dts - delay;
 647             if (dts != AV_NOPTS_VALUE && dts < pcr)
 648                 av_log(s, AV_LOG_WARNING, "dts < pcr, TS is invalid\n");
 649             *q++ = 7; /* AFC length */
 650             *q++ = 0x10; /* flags: PCR present */
 651             *q++ = pcr >> 25;
 652             *q++ = pcr >> 17;
 653             *q++ = pcr >> 9;
 654             *q++ = pcr >> 1;
 655             *q++ = (pcr & 1) << 7;
 656             *q++ = 0;
 657         }
 658         if (is_start) {
 659             int pes_extension = 0;
 660             /* write PES header */
 661             *q++ = 0x00;
 662             *q++ = 0x00;
 663             *q++ = 0x01;
 664             private_code = 0;
 665             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
 666                 if (st->codec->codec_id == CODEC_ID_DIRAC) {
 667                     *q++ = 0xfd;
 668                 } else
 669                     *q++ = 0xe0;
 670             } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
 671                        (st->codec->codec_id == CODEC_ID_MP2 ||
 672                         st->codec->codec_id == CODEC_ID_MP3)) {
 673                 *q++ = 0xc0;
 674             } else {
 675                 *q++ = 0xbd;
 676                 if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
 677                     private_code = 0x20;
 678                 }
 679             }
 680             header_len = 0;
 681             flags = 0;
 682             if (pts != AV_NOPTS_VALUE) {
 683                 header_len += 5;
 684                 flags |= 0x80;
 685             }
 686             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
 687                 header_len += 5;
 688                 flags |= 0x40;
 689             }
 690             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
 691                 st->codec->codec_id == CODEC_ID_DIRAC) {
 692                 /* set PES_extension_flag */
 693                 pes_extension = 1;
 694                 flags |= 0x01;
 695
 696                 /*
 697                 * One byte for PES2 extension flag +
 698                 * one byte for extension length +
 699                 * one byte for extension id
 700                 */
 701                 header_len += 3;
 702             }
 703             len = payload_size + header_len + 3;
 704             if (private_code != 0)
 705                 len++;
 706             if (len > 0xffff)
 707                 len = 0;
 708             *q++ = len >> 8;
 709             *q++ = len;
 710             val = 0x80;
 711             /* data alignment indicator is required for subtitle data */
 712             if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE)
 713                 val |= 0x04;
 714             *q++ = val;
 715             *q++ = flags;
 716             *q++ = header_len;
 717             if (pts != AV_NOPTS_VALUE) {
 718                 write_pts(q, flags >> 6, pts);
 719                 q += 5;
 720             }
 721             if (dts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE && dts != pts) {
 722                 write_pts(q, 1, dts);
 723                 q += 5;
 724             }
 725             if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {
 726                 flags = 0x01;  /* set PES_extension_flag_2 */
 727                 *q++ = flags;
 728                 *q++ = 0x80 | 0x01;  /* marker bit + extension length */
 729                 /*
 730                 * Set the stream id extension flag bit to 0 and
 731                 * write the extended stream id
 732                 */
 733                 *q++ = 0x00 | 0x60;
 734             }
 735             if (private_code != 0)
 736                 *q++ = private_code;
 737             is_start = 0;
 738         }
 739         /* header size */
 740         header_len = q - buf;
 741         /* data len */
 742         len = TS_PACKET_SIZE - header_len;
 743         if (len > payload_size)
 744             len = payload_size;
 745         stuffing_len = TS_PACKET_SIZE - header_len - len;
 746         if (stuffing_len > 0) {
 747             /* add stuffing with AFC */
 748             if (buf[3] & 0x20) {
 749                 /* stuffing already present: increase its size */
 750                 afc_len = buf[4] + 1;
 751                 memmove(buf + 4 + afc_len + stuffing_len,
 752                         buf + 4 + afc_len,
 753                         header_len - (4 + afc_len));
 754                 buf[4] += stuffing_len;
 755                 memset(buf + 4 + afc_len, 0xff, stuffing_len);
 756             } else {
 757                 /* add stuffing */
 758                 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
 759                 buf[3] |= 0x20;
 760                 buf[4] = stuffing_len - 1;
 761                 if (stuffing_len >= 2) {
 762                     buf[5] = 0x00;
 763                     memset(buf + 6, 0xff, stuffing_len - 2);
 764                 }
 765             }
 766         }
 767         memcpy(buf + TS_PACKET_SIZE - len, payload, len);
 768         payload += len;
 769         payload_size -= len;
 770         put_buffer(s->pb, buf, TS_PACKET_SIZE);
 771         ts->cur_pcr += TS_PACKET_SIZE*8*90000LL/ts->mux_rate;
 772     }
 773     put_flush_packet(s->pb);
 774 }
 775
 776 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
 777 {
 778     AVStream *st = s->streams[pkt->stream_index];
 779     int size = pkt->size;
 780     uint8_t *buf= pkt->data;
 781     uint8_t *data= NULL;
 782     MpegTSWriteStream *ts_st = st->priv_data;
 783     const uint64_t delay = av_rescale(s->max_delay, 90000, AV_TIME_BASE)*2;
 784     int64_t dts = AV_NOPTS_VALUE, pts = AV_NOPTS_VALUE;
 785
 786     if (pkt->pts != AV_NOPTS_VALUE)
 787         pts = pkt->pts + delay;
 788     if (pkt->dts != AV_NOPTS_VALUE)
 789         dts = pkt->dts + delay;
 790
 791     if (ts_st->first_pts_check && pts == AV_NOPTS_VALUE) {
 792         av_log(s, AV_LOG_ERROR, "first pts value must set\n");
 793         return -1;
 794     }
 795     ts_st->first_pts_check = 0;
 796
 797     if (st->codec->codec_id == CODEC_ID_H264) {
 798         const uint8_t *p = buf, *buf_end = p+size;
 799         uint32_t state = -1;
 800
 801         if (pkt->size < 5 || AV_RB32(pkt->data) != 0x0000001) {
 802             av_log(s, AV_LOG_ERROR, "h264 bitstream malformated, "
 803                    "no startcode found, use -vbsf h264_mp4toannexb\n");
 804             return -1;
 805         }
 806
 807         do {
 808             p = ff_find_start_code(p, buf_end, &state);
 809             //av_log(s, AV_LOG_INFO, "nal %d\n", state & 0x1f);
 810         } while (p < buf_end && (state & 0x1f) != 9 &&
 811                  (state & 0x1f) != 5 && (state & 0x1f) != 1);
 812
 813         if ((state & 0x1f) != 9) { // AUD NAL
 814             data = av_malloc(pkt->size+6);
 815             if (!data)
 816                 return -1;
 817             memcpy(data+6, pkt->data, pkt->size);
 818             AV_WB32(data, 0x00000001);
 819             data[4] = 0x09;
 820             data[5] = 0xe0; // any slice type
 821             buf  = data;
 822             size = pkt->size+6;
 823         }
 824     } else if (st->codec->codec_id == CODEC_ID_AAC) {
 825         if (pkt->size < 2)
 826             return -1;
 827         if ((AV_RB16(pkt->data) & 0xfff0) != 0xfff0) {
 828             ADTSContext *adts = ts_st->adts;
 829             int new_size;
 830             if (!adts) {
 831                 av_log(s, AV_LOG_ERROR, "aac bitstream not in adts format "
 832                        "and extradata missing\n");
 833                 return -1;
 834             }
 835             new_size = ADTS_HEADER_SIZE+adts->pce_size+pkt->size;
 836             if ((unsigned)new_size >= INT_MAX)
 837                 return -1;
 838             data = av_malloc(new_size);
 839             if (!data)
 840                 return AVERROR(ENOMEM);
 841             ff_adts_write_frame_header(adts, data, pkt->size, adts->pce_size);
 842             if (adts->pce_size) {
 843                 memcpy(data+ADTS_HEADER_SIZE, adts->pce_data, adts->pce_size);
 844                 adts->pce_size = 0;
 845             }
 846             memcpy(data+ADTS_HEADER_SIZE+adts->pce_size, pkt->data, pkt->size);
 847             buf = data;
 848             size = new_size;
 849         }
 850     }
 851
 852     if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO) {
 853         // for video and subtitle, write a single pes packet
 854         mpegts_write_pes(s, st, buf, size, pts, dts);
 855         av_free(data);
 856         return 0;
 857     }
 858
 859     if (ts_st->payload_index + size > DEFAULT_PES_PAYLOAD_SIZE) {
 860         mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
 861                          ts_st->payload_pts, ts_st->payload_dts);
 862         ts_st->payload_index = 0;
 863     }
 864
 865     if (!ts_st->payload_index) {
 866         ts_st->payload_pts = pts;
 867         ts_st->payload_dts = dts;
 868     }
 869
 870     memcpy(ts_st->payload + ts_st->payload_index, buf, size);
 871     ts_st->payload_index += size;
 872
 873     av_free(data);
 874
 875     return 0;
 876 }
 877
 878 static int mpegts_write_end(AVFormatContext *s)
 879 {
 880     MpegTSWrite *ts = s->priv_data;
 881     MpegTSWriteStream *ts_st;
 882     MpegTSService *service;
 883     AVStream *st;
 884     int i;
 885
 886     /* flush current packets */
 887     for(i = 0; i < s->nb_streams; i++) {
 888         st = s->streams[i];
 889         ts_st = st->priv_data;
 890         if (ts_st->payload_index > 0) {
 891             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
 892                              ts_st->payload_pts, ts_st->payload_dts);
 893         }
 894         av_freep(&ts_st->adts);
 895     }
 896     put_flush_packet(s->pb);
 897
 898     for(i = 0; i < ts->nb_services; i++) {
 899         service = ts->services[i];
 900         av_freep(&service->provider_name);
 901         av_freep(&service->name);
 902         av_free(service);
 903     }
 904     av_free(ts->services);
 905
 906     return 0;
 907 }
 908
 909 AVOutputFormat mpegts_muxer = {
 910     "mpegts",
 911     NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
 912     "video/x-mpegts",
 913     "ts,m2t",
 914     sizeof(MpegTSWrite),
 915     CODEC_ID_MP2,
 916     CODEC_ID_MPEG2VIDEO,
 917     mpegts_write_header,
 918     mpegts_write_packet,
 919     mpegts_write_end,
 920 };