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/crc.h"
  23 #include "avformat.h"
  24 #include "mpegts.h"
  25
  26 /* write DVB SI sections */
  27
  28 /*********************************************/
  29 /* mpegts section writer */
  30
  31 typedef struct MpegTSSection {
  32     int pid;
  33     int cc;
  34     void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
  35     void *opaque;
  36 } MpegTSSection;
  37
  38 /* NOTE: 4 bytes must be left at the end for the crc32 */
  39 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
  40 {
  41     unsigned int crc;
  42     unsigned char packet[TS_PACKET_SIZE];
  43     const unsigned char *buf_ptr;
  44     unsigned char *q;
  45     int first, b, len1, left;
  46
  47     crc = bswap_32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
  48     buf[len - 4] = (crc >> 24) & 0xff;
  49     buf[len - 3] = (crc >> 16) & 0xff;
  50     buf[len - 2] = (crc >> 8) & 0xff;
  51     buf[len - 1] = (crc) & 0xff;
  52
  53     /* send each packet */
  54     buf_ptr = buf;
  55     while (len > 0) {
  56         first = (buf == buf_ptr);
  57         q = packet;
  58         *q++ = 0x47;
  59         b = (s->pid >> 8);
  60         if (first)
  61             b |= 0x40;
  62         *q++ = b;
  63         *q++ = s->pid;
  64         *q++ = 0x10 | s->cc;
  65         s->cc = (s->cc + 1) & 0xf;
  66         if (first)
  67             *q++ = 0; /* 0 offset */
  68         len1 = TS_PACKET_SIZE - (q - packet);
  69         if (len1 > len)
  70             len1 = len;
  71         memcpy(q, buf_ptr, len1);
  72         q += len1;
  73         /* add known padding data */
  74         left = TS_PACKET_SIZE - (q - packet);
  75         if (left > 0)
  76             memset(q, 0xff, left);
  77
  78         s->write_packet(s, packet);
  79
  80         buf_ptr += len1;
  81         len -= len1;
  82     }
  83 }
  84
  85 static inline void put16(uint8_t **q_ptr, int val)
  86 {
  87     uint8_t *q;
  88     q = *q_ptr;
  89     *q++ = val >> 8;
  90     *q++ = val;
  91     *q_ptr = q;
  92 }
  93
  94 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
  95                           int version, int sec_num, int last_sec_num,
  96                           uint8_t *buf, int len)
  97 {
  98     uint8_t section[1024], *q;
  99     unsigned int tot_len;
 100
 101     tot_len = 3 + 5 + len + 4;
 102     /* check if not too big */
 103     if (tot_len > 1024)
 104         return -1;
 105
 106     q = section;
 107     *q++ = tid;
 108     put16(&q, 0xb000 | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
 109     put16(&q, id);
 110     *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
 111     *q++ = sec_num;
 112     *q++ = last_sec_num;
 113     memcpy(q, buf, len);
 114
 115     mpegts_write_section(s, section, tot_len);
 116     return 0;
 117 }
 118
 119 /*********************************************/
 120 /* mpegts writer */
 121
 122 #define DEFAULT_PMT_START_PID   0x1000
 123 #define DEFAULT_START_PID       0x0100
 124 #define DEFAULT_PROVIDER_NAME   "FFmpeg"
 125 #define DEFAULT_SERVICE_NAME    "Service01"
 126
 127 /* default network id, transport stream and service identifiers */
 128 #define DEFAULT_ONID            0x0001
 129 #define DEFAULT_TSID            0x0001
 130 #define DEFAULT_SID             0x0001
 131
 132 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
 133 #define DEFAULT_PES_HEADER_FREQ 16
 134 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
 135
 136 /* we retransmit the SI info at this rate */
 137 #define SDT_RETRANS_TIME 500
 138 #define PAT_RETRANS_TIME 100
 139 #define PCR_RETRANS_TIME 20
 140
 141 typedef struct MpegTSWriteStream {
 142     struct MpegTSService *service;
 143     int pid; /* stream associated pid */
 144     int cc;
 145     int payload_index;
 146     int64_t payload_pts;
 147     int64_t payload_dts;
 148     uint8_t payload[DEFAULT_PES_PAYLOAD_SIZE];
 149 } MpegTSWriteStream;
 150
 151 typedef struct MpegTSService {
 152     MpegTSSection pmt; /* MPEG2 pmt table context */
 153     int sid;           /* service ID */
 154     char *name;
 155     char *provider_name;
 156     int pcr_pid;
 157     int pcr_packet_count;
 158     int pcr_packet_freq;
 159 } MpegTSService;
 160
 161 typedef struct MpegTSWrite {
 162     MpegTSSection pat; /* MPEG2 pat table */
 163     MpegTSSection sdt; /* MPEG2 sdt table context */
 164     MpegTSService **services;
 165     int sdt_packet_count;
 166     int sdt_packet_freq;
 167     int pat_packet_count;
 168     int pat_packet_freq;
 169     int nb_services;
 170     int onid;
 171     int tsid;
 172 } MpegTSWrite;
 173
 174 static void mpegts_write_pat(AVFormatContext *s)
 175 {
 176     MpegTSWrite *ts = s->priv_data;
 177     MpegTSService *service;
 178     uint8_t data[1012], *q;
 179     int i;
 180
 181     q = data;
 182     for(i = 0; i < ts->nb_services; i++) {
 183         service = ts->services[i];
 184         put16(&q, service->sid);
 185         put16(&q, 0xe000 | service->pmt.pid);
 186     }
 187     mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
 188                           data, q - data);
 189 }
 190
 191 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
 192 {
 193     //    MpegTSWrite *ts = s->priv_data;
 194     uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
 195     int val, stream_type, i;
 196
 197     q = data;
 198     put16(&q, 0xe000 | service->pcr_pid);
 199
 200     program_info_length_ptr = q;
 201     q += 2; /* patched after */
 202
 203     /* put program info here */
 204
 205     val = 0xf000 | (q - program_info_length_ptr - 2);
 206     program_info_length_ptr[0] = val >> 8;
 207     program_info_length_ptr[1] = val;
 208
 209     for(i = 0; i < s->nb_streams; i++) {
 210         AVStream *st = s->streams[i];
 211         MpegTSWriteStream *ts_st = st->priv_data;
 212         switch(st->codec->codec_id) {
 213         case CODEC_ID_MPEG1VIDEO:
 214         case CODEC_ID_MPEG2VIDEO:
 215             stream_type = STREAM_TYPE_VIDEO_MPEG2;
 216             break;
 217         case CODEC_ID_MPEG4:
 218             stream_type = STREAM_TYPE_VIDEO_MPEG4;
 219             break;
 220         case CODEC_ID_H264:
 221             stream_type = STREAM_TYPE_VIDEO_H264;
 222             break;
 223         case CODEC_ID_DIRAC:
 224             stream_type = STREAM_TYPE_VIDEO_DIRAC;
 225             break;
 226         case CODEC_ID_MP2:
 227         case CODEC_ID_MP3:
 228             stream_type = STREAM_TYPE_AUDIO_MPEG1;
 229             break;
 230         case CODEC_ID_AAC:
 231             stream_type = STREAM_TYPE_AUDIO_AAC;
 232             break;
 233         case CODEC_ID_AC3:
 234             stream_type = STREAM_TYPE_AUDIO_AC3;
 235             break;
 236         default:
 237             stream_type = STREAM_TYPE_PRIVATE_DATA;
 238             break;
 239         }
 240         *q++ = stream_type;
 241         put16(&q, 0xe000 | ts_st->pid);
 242         desc_length_ptr = q;
 243         q += 2; /* patched after */
 244
 245         /* write optional descriptors here */
 246         switch(st->codec->codec_type) {
 247         case CODEC_TYPE_AUDIO:
 248             if (strlen(st->language) == 3) {
 249                 *q++ = 0x0a; /* ISO 639 language descriptor */
 250                 *q++ = 4;
 251                 *q++ = st->language[0];
 252                 *q++ = st->language[1];
 253                 *q++ = st->language[2];
 254                 *q++ = 0; /* undefined type */
 255             }
 256             break;
 257         case CODEC_TYPE_SUBTITLE:
 258             {
 259                 const char *language;
 260                 language = st->language;
 261                 if (strlen(language) != 3)
 262                     language = "eng";
 263                 *q++ = 0x59;
 264                 *q++ = 8;
 265                 *q++ = language[0];
 266                 *q++ = language[1];
 267                 *q++ = language[2];
 268                 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
 269                 put16(&q, 1); /* page id */
 270                 put16(&q, 1); /* ancillary page id */
 271             }
 272             break;
 273         case CODEC_TYPE_VIDEO:
 274             if (stream_type == STREAM_TYPE_VIDEO_DIRAC) {
 275                 *q++ = 0x05; /*MPEG-2 registration descriptor*/
 276                 *q++ = 4;
 277                 *q++ = 'd';
 278                 *q++ = 'r';
 279                 *q++ = 'a';
 280                 *q++ = 'c';
 281             }
 282             break;
 283         }
 284
 285         val = 0xf000 | (q - desc_length_ptr - 2);
 286         desc_length_ptr[0] = val >> 8;
 287         desc_length_ptr[1] = val;
 288     }
 289     mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
 290                           data, q - data);
 291 }
 292
 293 /* NOTE: str == NULL is accepted for an empty string */
 294 static void putstr8(uint8_t **q_ptr, const char *str)
 295 {
 296     uint8_t *q;
 297     int len;
 298
 299     q = *q_ptr;
 300     if (!str)
 301         len = 0;
 302     else
 303         len = strlen(str);
 304     *q++ = len;
 305     memcpy(q, str, len);
 306     q += len;
 307     *q_ptr = q;
 308 }
 309
 310 static void mpegts_write_sdt(AVFormatContext *s)
 311 {
 312     MpegTSWrite *ts = s->priv_data;
 313     MpegTSService *service;
 314     uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
 315     int i, running_status, free_ca_mode, val;
 316
 317     q = data;
 318     put16(&q, ts->onid);
 319     *q++ = 0xff;
 320     for(i = 0; i < ts->nb_services; i++) {
 321         service = ts->services[i];
 322         put16(&q, service->sid);
 323         *q++ = 0xfc | 0x00; /* currently no EIT info */
 324         desc_list_len_ptr = q;
 325         q += 2;
 326         running_status = 4; /* running */
 327         free_ca_mode = 0;
 328
 329         /* write only one descriptor for the service name and provider */
 330         *q++ = 0x48;
 331         desc_len_ptr = q;
 332         q++;
 333         *q++ = 0x01; /* digital television service */
 334         putstr8(&q, service->provider_name);
 335         putstr8(&q, service->name);
 336         desc_len_ptr[0] = q - desc_len_ptr - 1;
 337
 338         /* fill descriptor length */
 339         val = (running_status << 13) | (free_ca_mode << 12) |
 340             (q - desc_list_len_ptr - 2);
 341         desc_list_len_ptr[0] = val >> 8;
 342         desc_list_len_ptr[1] = val;
 343     }
 344     mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
 345                           data, q - data);
 346 }
 347
 348 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
 349                                          int sid,
 350                                          const char *provider_name,
 351                                          const char *name)
 352 {
 353     MpegTSService *service;
 354
 355     service = av_mallocz(sizeof(MpegTSService));
 356     if (!service)
 357         return NULL;
 358     service->pmt.pid = DEFAULT_PMT_START_PID + ts->nb_services - 1;
 359     service->sid = sid;
 360     service->provider_name = av_strdup(provider_name);
 361     service->name = av_strdup(name);
 362     service->pcr_pid = 0x1fff;
 363     dynarray_add(&ts->services, &ts->nb_services, service);
 364     return service;
 365 }
 366
 367 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
 368 {
 369     AVFormatContext *ctx = s->opaque;
 370     put_buffer(ctx->pb, packet, TS_PACKET_SIZE);
 371 }
 372
 373 static int mpegts_write_header(AVFormatContext *s)
 374 {
 375     MpegTSWrite *ts = s->priv_data;
 376     MpegTSWriteStream *ts_st;
 377     MpegTSService *service;
 378     AVStream *st;
 379     int i, total_bit_rate;
 380     const char *service_name;
 381
 382     ts->tsid = DEFAULT_TSID;
 383     ts->onid = DEFAULT_ONID;
 384     /* allocate a single DVB service */
 385     service_name = s->title;
 386     if (service_name[0] == '\0')
 387         service_name = DEFAULT_SERVICE_NAME;
 388     service = mpegts_add_service(ts, DEFAULT_SID,
 389                                  DEFAULT_PROVIDER_NAME, service_name);
 390     service->pmt.write_packet = section_write_packet;
 391     service->pmt.opaque = s;
 392
 393     ts->pat.pid = PAT_PID;
 394     ts->pat.cc = 0;
 395     ts->pat.write_packet = section_write_packet;
 396     ts->pat.opaque = s;
 397
 398     ts->sdt.pid = SDT_PID;
 399     ts->sdt.cc = 0;
 400     ts->sdt.write_packet = section_write_packet;
 401     ts->sdt.opaque = s;
 402
 403     /* assign pids to each stream */
 404     total_bit_rate = 0;
 405     for(i = 0;i < s->nb_streams; i++) {
 406         st = s->streams[i];
 407         ts_st = av_mallocz(sizeof(MpegTSWriteStream));
 408         if (!ts_st)
 409             goto fail;
 410         st->priv_data = ts_st;
 411         ts_st->service = service;
 412         ts_st->pid = DEFAULT_START_PID + i;
 413         ts_st->payload_pts = AV_NOPTS_VALUE;
 414         ts_st->payload_dts = AV_NOPTS_VALUE;
 415         /* update PCR pid by using the first video stream */
 416         if (st->codec->codec_type == CODEC_TYPE_VIDEO &&
 417             service->pcr_pid == 0x1fff)
 418             service->pcr_pid = ts_st->pid;
 419         total_bit_rate += st->codec->bit_rate;
 420     }
 421
 422     /* if no video stream, use the first stream as PCR */
 423     if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
 424         ts_st = s->streams[0]->priv_data;
 425         service->pcr_pid = ts_st->pid;
 426     }
 427
 428     if (total_bit_rate <= 8 * 1024)
 429         total_bit_rate = 8 * 1024;
 430     service->pcr_packet_freq = (total_bit_rate * PCR_RETRANS_TIME) /
 431         (TS_PACKET_SIZE * 8 * 1000);
 432     ts->sdt_packet_freq = (total_bit_rate * SDT_RETRANS_TIME) /
 433         (TS_PACKET_SIZE * 8 * 1000);
 434     ts->pat_packet_freq = (total_bit_rate * PAT_RETRANS_TIME) /
 435         (TS_PACKET_SIZE * 8 * 1000);
 436 #if 0
 437     printf("%d %d %d\n",
 438            total_bit_rate, ts->sdt_packet_freq, ts->pat_packet_freq);
 439 #endif
 440
 441     /* write info at the start of the file, so that it will be fast to
 442        find them */
 443     mpegts_write_sdt(s);
 444     mpegts_write_pat(s);
 445     for(i = 0; i < ts->nb_services; i++) {
 446         mpegts_write_pmt(s, ts->services[i]);
 447     }
 448     put_flush_packet(s->pb);
 449
 450     return 0;
 451
 452  fail:
 453     for(i = 0;i < s->nb_streams; i++) {
 454         st = s->streams[i];
 455         av_free(st->priv_data);
 456     }
 457     return -1;
 458 }
 459
 460 /* send SDT, PAT and PMT tables regulary */
 461 static void retransmit_si_info(AVFormatContext *s)
 462 {
 463     MpegTSWrite *ts = s->priv_data;
 464     int i;
 465
 466     if (++ts->sdt_packet_count == ts->sdt_packet_freq) {
 467         ts->sdt_packet_count = 0;
 468         mpegts_write_sdt(s);
 469     }
 470     if (++ts->pat_packet_count == ts->pat_packet_freq) {
 471         ts->pat_packet_count = 0;
 472         mpegts_write_pat(s);
 473         for(i = 0; i < ts->nb_services; i++) {
 474             mpegts_write_pmt(s, ts->services[i]);
 475         }
 476     }
 477 }
 478
 479 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
 480 {
 481     int val;
 482
 483     val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
 484     *q++ = val;
 485     val = (((pts >> 15) & 0x7fff) << 1) | 1;
 486     *q++ = val >> 8;
 487     *q++ = val;
 488     val = (((pts) & 0x7fff) << 1) | 1;
 489     *q++ = val >> 8;
 490     *q++ = val;
 491 }
 492
 493 /* NOTE: pes_data contains all the PES packet */
 494 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
 495                              const uint8_t *payload, int payload_size,
 496                              int64_t pts, int64_t dts)
 497 {
 498     MpegTSWriteStream *ts_st = st->priv_data;
 499     uint8_t buf[TS_PACKET_SIZE];
 500     uint8_t *q;
 501     int val, is_start, len, header_len, write_pcr, private_code, flags;
 502     int afc_len, stuffing_len;
 503     int64_t pcr = -1; /* avoid warning */
 504
 505     is_start = 1;
 506     while (payload_size > 0) {
 507         retransmit_si_info(s);
 508
 509         write_pcr = 0;
 510         if (ts_st->pid == ts_st->service->pcr_pid) {
 511             ts_st->service->pcr_packet_count++;
 512             if (ts_st->service->pcr_packet_count >=
 513                 ts_st->service->pcr_packet_freq) {
 514                 ts_st->service->pcr_packet_count = 0;
 515                 write_pcr = 1;
 516                 /* XXX: this is incorrect, but at least we have a PCR
 517                    value */
 518                 pcr = pts;
 519             }
 520         }
 521
 522         /* prepare packet header */
 523         q = buf;
 524         *q++ = 0x47;
 525         val = (ts_st->pid >> 8);
 526         if (is_start)
 527             val |= 0x40;
 528         *q++ = val;
 529         *q++ = ts_st->pid;
 530         *q++ = 0x10 | ts_st->cc | (write_pcr ? 0x20 : 0);
 531         ts_st->cc = (ts_st->cc + 1) & 0xf;
 532         if (write_pcr) {
 533             *q++ = 7; /* AFC length */
 534             *q++ = 0x10; /* flags: PCR present */
 535             *q++ = pcr >> 25;
 536             *q++ = pcr >> 17;
 537             *q++ = pcr >> 9;
 538             *q++ = pcr >> 1;
 539             *q++ = (pcr & 1) << 7;
 540             *q++ = 0;
 541         }
 542         if (is_start) {
 543             int pes_extension = 0;
 544             /* write PES header */
 545             *q++ = 0x00;
 546             *q++ = 0x00;
 547             *q++ = 0x01;
 548             private_code = 0;
 549             if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
 550                 if (st->codec->codec_id == CODEC_ID_DIRAC) {
 551                     *q++ = 0xfd;
 552                 } else
 553                     *q++ = 0xe0;
 554             } else if (st->codec->codec_type == CODEC_TYPE_AUDIO &&
 555                        (st->codec->codec_id == CODEC_ID_MP2 ||
 556                         st->codec->codec_id == CODEC_ID_MP3)) {
 557                 *q++ = 0xc0;
 558             } else {
 559                 *q++ = 0xbd;
 560                 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
 561                     private_code = 0x20;
 562                 }
 563             }
 564             header_len = 0;
 565             flags = 0;
 566             if (pts != AV_NOPTS_VALUE) {
 567                 header_len += 5;
 568                 flags |= 0x80;
 569             }
 570             if (dts != AV_NOPTS_VALUE) {
 571                 header_len += 5;
 572                 flags |= 0x40;
 573             }
 574             if (st->codec->codec_type == CODEC_TYPE_VIDEO &&
 575                 st->codec->codec_id == CODEC_ID_DIRAC) {
 576                 /* set PES_extension_flag */
 577                 pes_extension = 1;
 578                 flags |= 0x01;
 579
 580                 /*
 581                 * One byte for PES2 extension flag +
 582                 * one byte for extension length +
 583                 * one byte for extension id
 584                 */
 585                 header_len += 3;
 586             }
 587             len = payload_size + header_len + 3;
 588             if (private_code != 0)
 589                 len++;
 590             *q++ = len >> 8;
 591             *q++ = len;
 592             val = 0x80;
 593             /* data alignment indicator is required for subtitle data */
 594             if (st->codec->codec_type == CODEC_TYPE_SUBTITLE)
 595                 val |= 0x04;
 596             *q++ = val;
 597             *q++ = flags;
 598             *q++ = header_len;
 599             if (pts != AV_NOPTS_VALUE) {
 600                 write_pts(q, flags >> 6, pts);
 601                 q += 5;
 602             }
 603             if (dts != AV_NOPTS_VALUE) {
 604                 write_pts(q, 1, dts);
 605                 q += 5;
 606             }
 607             if (pes_extension && st->codec->codec_id == CODEC_ID_DIRAC) {
 608                 flags = 0x01;  /* set PES_extension_flag_2 */
 609                 *q++ = flags;
 610                 *q++ = 0x80 | 0x01;  /* marker bit + extension length */
 611                 /*
 612                 * Set the stream id extension flag bit to 0 and
 613                 * write the extended stream id
 614                 */
 615                 *q++ = 0x00 | 0x60;
 616             }
 617             if (private_code != 0)
 618                 *q++ = private_code;
 619             is_start = 0;
 620         }
 621         /* header size */
 622         header_len = q - buf;
 623         /* data len */
 624         len = TS_PACKET_SIZE - header_len;
 625         if (len > payload_size)
 626             len = payload_size;
 627         stuffing_len = TS_PACKET_SIZE - header_len - len;
 628         if (stuffing_len > 0) {
 629             /* add stuffing with AFC */
 630             if (buf[3] & 0x20) {
 631                 /* stuffing already present: increase its size */
 632                 afc_len = buf[4] + 1;
 633                 memmove(buf + 4 + afc_len + stuffing_len,
 634                         buf + 4 + afc_len,
 635                         header_len - (4 + afc_len));
 636                 buf[4] += stuffing_len;
 637                 memset(buf + 4 + afc_len, 0xff, stuffing_len);
 638             } else {
 639                 /* add stuffing */
 640                 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
 641                 buf[3] |= 0x20;
 642                 buf[4] = stuffing_len - 1;
 643                 if (stuffing_len >= 2) {
 644                     buf[5] = 0x00;
 645                     memset(buf + 6, 0xff, stuffing_len - 2);
 646                 }
 647             }
 648         }
 649         memcpy(buf + TS_PACKET_SIZE - len, payload, len);
 650         payload += len;
 651         payload_size -= len;
 652         put_buffer(s->pb, buf, TS_PACKET_SIZE);
 653     }
 654     put_flush_packet(s->pb);
 655 }
 656
 657 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
 658 {
 659     AVStream *st = s->streams[pkt->stream_index];
 660     int size= pkt->size;
 661     uint8_t *buf= pkt->data;
 662     MpegTSWriteStream *ts_st = st->priv_data;
 663     int len, max_payload_size;
 664
 665     if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
 666         /* for subtitle, a single PES packet must be generated */
 667         mpegts_write_pes(s, st, buf, size, pkt->pts, AV_NOPTS_VALUE);
 668         return 0;
 669     }
 670
 671     if (st->codec->codec_id == CODEC_ID_DIRAC) {
 672         /* for Dirac, a single PES packet must be generated */
 673         mpegts_write_pes(s, st, buf, size, pkt->pts, pkt->dts);
 674         return 0;
 675     }
 676     max_payload_size = DEFAULT_PES_PAYLOAD_SIZE;
 677     while (size > 0) {
 678         len = max_payload_size - ts_st->payload_index;
 679         if (len > size)
 680             len = size;
 681         memcpy(ts_st->payload + ts_st->payload_index, buf, len);
 682         buf += len;
 683         size -= len;
 684         ts_st->payload_index += len;
 685         if (ts_st->payload_pts == AV_NOPTS_VALUE)
 686             ts_st->payload_pts = pkt->pts;
 687         if (ts_st->payload_dts == AV_NOPTS_VALUE)
 688             ts_st->payload_dts = pkt->dts;
 689         if (ts_st->payload_index >= max_payload_size) {
 690             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
 691                              ts_st->payload_pts, ts_st->payload_dts);
 692             ts_st->payload_pts = AV_NOPTS_VALUE;
 693             ts_st->payload_dts = AV_NOPTS_VALUE;
 694             ts_st->payload_index = 0;
 695         }
 696     }
 697     return 0;
 698 }
 699
 700 static int mpegts_write_end(AVFormatContext *s)
 701 {
 702     MpegTSWrite *ts = s->priv_data;
 703     MpegTSWriteStream *ts_st;
 704     MpegTSService *service;
 705     AVStream *st;
 706     int i;
 707
 708     /* flush current packets */
 709     for(i = 0; i < s->nb_streams; i++) {
 710         st = s->streams[i];
 711         ts_st = st->priv_data;
 712         if (ts_st->payload_index > 0) {
 713             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
 714                              ts_st->payload_pts, ts_st->payload_dts);
 715         }
 716     }
 717     put_flush_packet(s->pb);
 718
 719     for(i = 0; i < ts->nb_services; i++) {
 720         service = ts->services[i];
 721         av_freep(&service->provider_name);
 722         av_freep(&service->name);
 723         av_free(service);
 724     }
 725     av_free(ts->services);
 726
 727     return 0;
 728 }
 729
 730 AVOutputFormat mpegts_muxer = {
 731     "mpegts",
 732     NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),
 733     "video/x-mpegts",
 734     "ts,m2t",
 735     sizeof(MpegTSWrite),
 736     CODEC_ID_MP2,
 737     CODEC_ID_MPEG2VIDEO,
 738     mpegts_write_header,
 739     mpegts_write_packet,
 740     mpegts_write_end,
 741 };