libavformat/mpegtsenc.c

   1 /*
   2  * MPEG2 transport stream (aka DVB) mux
   3  * Copyright (c) 2003 Fabrice Bellard.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19 #include "avformat.h"
  20
  21 #include "mpegts.h"
  22
  23 /* write DVB SI sections */
  24
  25 static const uint32_t crc_table[256] = {
  26         0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
  27         0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
  28         0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70, 0x48d0c6c7,
  29         0x4593e01e, 0x4152fda9, 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
  30         0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3,
  31         0x709f7b7a, 0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
  32         0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58, 0xbaea46ef,
  33         0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
  34         0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, 0xc7361b4c, 0xc3f706fb,
  35         0xceb42022, 0xca753d95, 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
  36         0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
  37         0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
  38         0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13, 0x054bf6a4,
  39         0x0808d07d, 0x0cc9cdca, 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
  40         0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08,
  41         0x571d7dd1, 0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
  42         0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b, 0xbb60adfc,
  43         0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
  44         0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, 0xe0b41de7, 0xe4750050,
  45         0xe9362689, 0xedf73b3e, 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
  46         0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
  47         0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
  48         0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56, 0x4bc510e1,
  49         0x46863638, 0x42472b8f, 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
  50         0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5,
  51         0x3f9b762c, 0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
  52         0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e, 0xf5ee4bb9,
  53         0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
  54         0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, 0xc423cd6a, 0xc0e2d0dd,
  55         0xcda1f604, 0xc960ebb3, 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
  56         0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
  57         0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
  58         0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645, 0x4a4ffbf2,
  59         0x470cdd2b, 0x43cdc09c, 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
  60         0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e,
  61         0x18197087, 0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
  62         0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d, 0x2056cd3a,
  63         0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
  64         0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, 0xe3a1cbc1, 0xe760d676,
  65         0xea23f0af, 0xeee2ed18, 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
  66         0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
  67         0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
  68         0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
  69 };
  70
  71 unsigned int mpegts_crc32(const uint8_t *data, int len)
  72 {
  73     register int i;
  74     unsigned int crc = 0xffffffff;
  75
  76     for (i=0; i<len; i++)
  77         crc = (crc << 8) ^ crc_table[((crc >> 24) ^ *data++) & 0xff];
  78
  79     return crc;
  80 }
  81
  82 /*********************************************/
  83 /* mpegts section writer */
  84
  85 typedef struct MpegTSSection {
  86     int pid;
  87     int cc;
  88     void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
  89     void *opaque;
  90 } MpegTSSection;
  91
  92 /* NOTE: 4 bytes must be left at the end for the crc32 */
  93 void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
  94 {
  95     unsigned int crc;
  96     unsigned char packet[TS_PACKET_SIZE];
  97     const unsigned char *buf_ptr;
  98     unsigned char *q;
  99     int first, b, len1, left;
 100
 101     crc = mpegts_crc32(buf, len - 4);
 102     buf[len - 4] = (crc >> 24) & 0xff;
 103     buf[len - 3] = (crc >> 16) & 0xff;
 104     buf[len - 2] = (crc >> 8) & 0xff;
 105     buf[len - 1] = (crc) & 0xff;
 106
 107     /* send each packet */
 108     buf_ptr = buf;
 109     while (len > 0) {
 110         first = (buf == buf_ptr);
 111         q = packet;
 112         *q++ = 0x47;
 113         b = (s->pid >> 8);
 114         if (first)
 115             b |= 0x40;
 116         *q++ = b;
 117         *q++ = s->pid;
 118         s->cc = (s->cc + 1) & 0xf;
 119         *q++ = 0x10 | s->cc;
 120         if (first)
 121             *q++ = 0; /* 0 offset */
 122         len1 = TS_PACKET_SIZE - (q - packet);
 123         if (len1 > len)
 124             len1 = len;
 125         memcpy(q, buf_ptr, len1);
 126         q += len1;
 127         /* add known padding data */
 128         left = TS_PACKET_SIZE - (q - packet);
 129         if (left > 0)
 130             memset(q, 0xff, left);
 131
 132         s->write_packet(s, packet);
 133
 134         buf_ptr += len1;
 135         len -= len1;
 136     }
 137 }
 138
 139 static inline void put16(uint8_t **q_ptr, int val)
 140 {
 141     uint8_t *q;
 142     q = *q_ptr;
 143     *q++ = val >> 8;
 144     *q++ = val;
 145     *q_ptr = q;
 146 }
 147
 148 int mpegts_write_section1(MpegTSSection *s, int tid, int id,
 149                           int version, int sec_num, int last_sec_num,
 150                           uint8_t *buf, int len)
 151 {
 152     uint8_t section[1024], *q;
 153     unsigned int tot_len;
 154
 155     tot_len = 3 + 5 + len + 4;
 156     /* check if not too big */
 157     if (tot_len > 1024)
 158         return -1;
 159
 160     q = section;
 161     *q++ = tid;
 162     put16(&q, 0xb000 | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
 163     put16(&q, id);
 164     *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
 165     *q++ = sec_num;
 166     *q++ = last_sec_num;
 167     memcpy(q, buf, len);
 168
 169     mpegts_write_section(s, section, tot_len);
 170     return 0;
 171 }
 172
 173 /*********************************************/
 174 /* mpegts writer */
 175
 176 #define DEFAULT_PMT_START_PID   0x1000
 177 #define DEFAULT_START_PID       0x0100
 178 #define DEFAULT_PROVIDER_NAME   "FFmpeg"
 179 #define DEFAULT_SERVICE_NAME    "Service01"
 180
 181 /* default network id, transport stream and service identifiers */
 182 #define DEFAULT_ONID            0x0001
 183 #define DEFAULT_TSID            0x0001
 184 #define DEFAULT_SID             0x0001
 185
 186 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
 187 #define DEFAULT_PES_HEADER_FREQ 16
 188 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
 189
 190 /* we retransmit the SI info at this rate */
 191 #define SDT_RETRANS_TIME 500
 192 #define PAT_RETRANS_TIME 100
 193 #define PCR_RETRANS_TIME 20
 194
 195 typedef struct MpegTSWriteStream {
 196     struct MpegTSService *service;
 197     int pid; /* stream associated pid */
 198     int cc;
 199     int payload_index;
 200     int64_t payload_pts;
 201     uint8_t payload[DEFAULT_PES_PAYLOAD_SIZE];
 202 } MpegTSWriteStream;
 203
 204 typedef struct MpegTSService {
 205     MpegTSSection pmt; /* MPEG2 pmt table context */
 206     int sid;           /* service ID */
 207     char *name;
 208     char *provider_name;
 209     int pcr_pid;
 210     int pcr_packet_count;
 211     int pcr_packet_freq;
 212 } MpegTSService;
 213
 214 typedef struct MpegTSWrite {
 215     MpegTSSection pat; /* MPEG2 pat table */
 216     MpegTSSection sdt; /* MPEG2 sdt table context */
 217     MpegTSService **services;
 218     int sdt_packet_count;
 219     int sdt_packet_freq;
 220     int pat_packet_count;
 221     int pat_packet_freq;
 222     int nb_services;
 223     int onid;
 224     int tsid;
 225 } MpegTSWrite;
 226
 227 static void mpegts_write_pat(AVFormatContext *s)
 228 {
 229     MpegTSWrite *ts = s->priv_data;
 230     MpegTSService *service;
 231     uint8_t data[1012], *q;
 232     int i;
 233
 234     q = data;
 235     for(i = 0; i < ts->nb_services; i++) {
 236         service = ts->services[i];
 237         put16(&q, service->sid);
 238         put16(&q, 0xe000 | service->pmt.pid);
 239     }
 240     mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
 241                           data, q - data);
 242 }
 243
 244 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
 245 {
 246     //    MpegTSWrite *ts = s->priv_data;
 247     uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
 248     int val, stream_type, i;
 249
 250     q = data;
 251     put16(&q, 0xe000 | service->pcr_pid);
 252
 253     program_info_length_ptr = q;
 254     q += 2; /* patched after */
 255
 256     /* put program info here */
 257
 258     val = 0xf000 | (q - program_info_length_ptr - 2);
 259     program_info_length_ptr[0] = val >> 8;
 260     program_info_length_ptr[1] = val;
 261
 262     for(i = 0; i < s->nb_streams; i++) {
 263         AVStream *st = s->streams[i];
 264         MpegTSWriteStream *ts_st = st->priv_data;
 265         switch(st->codec.codec_id) {
 266         case CODEC_ID_MPEG1VIDEO:
 267         case CODEC_ID_MPEG2VIDEO:
 268             stream_type = STREAM_TYPE_VIDEO_MPEG2;
 269             break;
 270         case CODEC_ID_MPEG4:
 271             stream_type = STREAM_TYPE_VIDEO_MPEG4;
 272             break;
 273         case CODEC_ID_H264:
 274             stream_type = STREAM_TYPE_VIDEO_H264;
 275             break;
 276         case CODEC_ID_MP2:
 277         case CODEC_ID_MP3:
 278             stream_type = STREAM_TYPE_AUDIO_MPEG1;
 279             break;
 280         case CODEC_ID_AAC:
 281             stream_type = STREAM_TYPE_AUDIO_AAC;
 282             break;
 283         case CODEC_ID_AC3:
 284             stream_type = STREAM_TYPE_AUDIO_AC3;
 285             break;
 286         default:
 287             stream_type = STREAM_TYPE_PRIVATE_DATA;
 288             break;
 289         }
 290         *q++ = stream_type;
 291         put16(&q, 0xe000 | ts_st->pid);
 292         desc_length_ptr = q;
 293         q += 2; /* patched after */
 294
 295         /* write optional descriptors here */
 296         switch(st->codec.codec_type) {
 297         case CODEC_TYPE_AUDIO:
 298             if (strlen(st->language) == 3) {
 299                 *q++ = 0x0a; /* ISO 639 language descriptor */
 300                 *q++ = 4;
 301                 *q++ = st->language[0];
 302                 *q++ = st->language[1];
 303                 *q++ = st->language[2];
 304                 *q++ = 0; /* undefined type */
 305             }
 306             break;
 307         case CODEC_TYPE_SUBTITLE:
 308             {
 309                 const char *language;
 310                 language = st->language;
 311                 if (strlen(language) != 3)
 312                     language = "eng";
 313                 *q++ = 0x59;
 314                 *q++ = 8;
 315                 *q++ = language[0];
 316                 *q++ = language[1];
 317                 *q++ = language[2];
 318                 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
 319                 put16(&q, 1); /* page id */
 320                 put16(&q, 1); /* ancillary page id */
 321             }
 322             break;
 323         }
 324
 325         val = 0xf000 | (q - desc_length_ptr - 2);
 326         desc_length_ptr[0] = val >> 8;
 327         desc_length_ptr[1] = val;
 328     }
 329     mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
 330                           data, q - data);
 331 }
 332
 333 /* NOTE: str == NULL is accepted for an empty string */
 334 static void putstr8(uint8_t **q_ptr, const char *str)
 335 {
 336     uint8_t *q;
 337     int len;
 338
 339     q = *q_ptr;
 340     if (!str)
 341         len = 0;
 342     else
 343         len = strlen(str);
 344     *q++ = len;
 345     memcpy(q, str, len);
 346     q += len;
 347     *q_ptr = q;
 348 }
 349
 350 static void mpegts_write_sdt(AVFormatContext *s)
 351 {
 352     MpegTSWrite *ts = s->priv_data;
 353     MpegTSService *service;
 354     uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
 355     int i, running_status, free_ca_mode, val;
 356
 357     q = data;
 358     put16(&q, ts->onid);
 359     *q++ = 0xff;
 360     for(i = 0; i < ts->nb_services; i++) {
 361         service = ts->services[i];
 362         put16(&q, service->sid);
 363         *q++ = 0xfc | 0x00; /* currently no EIT info */
 364         desc_list_len_ptr = q;
 365         q += 2;
 366         running_status = 4; /* running */
 367         free_ca_mode = 0;
 368
 369         /* write only one descriptor for the service name and provider */
 370         *q++ = 0x48;
 371         desc_len_ptr = q;
 372         q++;
 373         *q++ = 0x01; /* digital television service */
 374         putstr8(&q, service->provider_name);
 375         putstr8(&q, service->name);
 376         desc_len_ptr[0] = q - desc_len_ptr - 1;
 377
 378         /* fill descriptor length */
 379         val = (running_status << 13) | (free_ca_mode << 12) |
 380             (q - desc_list_len_ptr - 2);
 381         desc_list_len_ptr[0] = val >> 8;
 382         desc_list_len_ptr[1] = val;
 383     }
 384     mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
 385                           data, q - data);
 386 }
 387
 388 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
 389                                          int sid,
 390                                          const char *provider_name,
 391                                          const char *name)
 392 {
 393     MpegTSService *service;
 394
 395     service = av_mallocz(sizeof(MpegTSService));
 396     if (!service)
 397         return NULL;
 398     service->pmt.pid = DEFAULT_PMT_START_PID + ts->nb_services - 1;
 399     service->sid = sid;
 400     service->provider_name = av_strdup(provider_name);
 401     service->name = av_strdup(name);
 402     service->pcr_pid = 0x1fff;
 403     dynarray_add(&ts->services, &ts->nb_services, service);
 404     return service;
 405 }
 406
 407 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
 408 {
 409     AVFormatContext *ctx = s->opaque;
 410     put_buffer(&ctx->pb, packet, TS_PACKET_SIZE);
 411 }
 412
 413 static int mpegts_write_header(AVFormatContext *s)
 414 {
 415     MpegTSWrite *ts = s->priv_data;
 416     MpegTSWriteStream *ts_st;
 417     MpegTSService *service;
 418     AVStream *st;
 419     int i, total_bit_rate;
 420     const char *service_name;
 421
 422     ts->tsid = DEFAULT_TSID;
 423     ts->onid = DEFAULT_ONID;
 424     /* allocate a single DVB service */
 425     service_name = s->title;
 426     if (service_name[0] == '\0')
 427         service_name = DEFAULT_SERVICE_NAME;
 428     service = mpegts_add_service(ts, DEFAULT_SID,
 429                                  DEFAULT_PROVIDER_NAME, service_name);
 430     service->pmt.write_packet = section_write_packet;
 431     service->pmt.opaque = s;
 432
 433     ts->pat.pid = PAT_PID;
 434     ts->pat.cc = 0;
 435     ts->pat.write_packet = section_write_packet;
 436     ts->pat.opaque = s;
 437
 438     ts->sdt.pid = SDT_PID;
 439     ts->sdt.cc = 0;
 440     ts->sdt.write_packet = section_write_packet;
 441     ts->sdt.opaque = s;
 442
 443     /* assign pids to each stream */
 444     total_bit_rate = 0;
 445     for(i = 0;i < s->nb_streams; i++) {
 446         st = s->streams[i];
 447         ts_st = av_mallocz(sizeof(MpegTSWriteStream));
 448         if (!ts_st)
 449             goto fail;
 450         st->priv_data = ts_st;
 451         ts_st->service = service;
 452         ts_st->pid = DEFAULT_START_PID + i;
 453         ts_st->payload_pts = AV_NOPTS_VALUE;
 454         /* update PCR pid by using the first video stream */
 455         if (st->codec.codec_type == CODEC_TYPE_VIDEO &&
 456             service->pcr_pid == 0x1fff)
 457             service->pcr_pid = ts_st->pid;
 458         total_bit_rate += st->codec.bit_rate;
 459     }
 460
 461     /* if no video stream, use the first stream as PCR */
 462     if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
 463         ts_st = s->streams[0]->priv_data;
 464         service->pcr_pid = ts_st->pid;
 465     }
 466
 467     if (total_bit_rate <= 8 * 1024)
 468         total_bit_rate = 8 * 1024;
 469     service->pcr_packet_freq = (total_bit_rate * PCR_RETRANS_TIME) /
 470         (TS_PACKET_SIZE * 8 * 1000);
 471     ts->sdt_packet_freq = (total_bit_rate * SDT_RETRANS_TIME) /
 472         (TS_PACKET_SIZE * 8 * 1000);
 473     ts->pat_packet_freq = (total_bit_rate * PAT_RETRANS_TIME) /
 474         (TS_PACKET_SIZE * 8 * 1000);
 475 #if 0
 476     printf("%d %d %d\n",
 477            total_bit_rate, ts->sdt_packet_freq, ts->pat_packet_freq);
 478 #endif
 479
 480     /* write info at the start of the file, so that it will be fast to
 481        find them */
 482     mpegts_write_sdt(s);
 483     mpegts_write_pat(s);
 484     for(i = 0; i < ts->nb_services; i++) {
 485         mpegts_write_pmt(s, ts->services[i]);
 486     }
 487     put_flush_packet(&s->pb);
 488
 489     return 0;
 490
 491  fail:
 492     for(i = 0;i < s->nb_streams; i++) {
 493         st = s->streams[i];
 494         av_free(st->priv_data);
 495     }
 496     return -1;
 497 }
 498
 499 /* send SDT, PAT and PMT tables regulary */
 500 static void retransmit_si_info(AVFormatContext *s)
 501 {
 502     MpegTSWrite *ts = s->priv_data;
 503     int i;
 504
 505     if (++ts->sdt_packet_count == ts->sdt_packet_freq) {
 506         ts->sdt_packet_count = 0;
 507         mpegts_write_sdt(s);
 508     }
 509     if (++ts->pat_packet_count == ts->pat_packet_freq) {
 510         ts->pat_packet_count = 0;
 511         mpegts_write_pat(s);
 512         for(i = 0; i < ts->nb_services; i++) {
 513             mpegts_write_pmt(s, ts->services[i]);
 514         }
 515     }
 516 }
 517
 518 /* NOTE: pes_data contains all the PES packet */
 519 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
 520                              const uint8_t *payload, int payload_size,
 521                              int64_t pts)
 522 {
 523     MpegTSWriteStream *ts_st = st->priv_data;
 524     uint8_t buf[TS_PACKET_SIZE];
 525     uint8_t *q;
 526     int val, is_start, len, header_len, write_pcr, private_code;
 527     int afc_len, stuffing_len;
 528     int64_t pcr = -1; /* avoid warning */
 529
 530     is_start = 1;
 531     while (payload_size > 0) {
 532         retransmit_si_info(s);
 533
 534         write_pcr = 0;
 535         if (ts_st->pid == ts_st->service->pcr_pid) {
 536             ts_st->service->pcr_packet_count++;
 537             if (ts_st->service->pcr_packet_count >=
 538                 ts_st->service->pcr_packet_freq) {
 539                 ts_st->service->pcr_packet_count = 0;
 540                 write_pcr = 1;
 541                 /* XXX: this is incorrect, but at least we have a PCR
 542                    value */
 543                 pcr = pts;
 544             }
 545         }
 546
 547         /* prepare packet header */
 548         q = buf;
 549         *q++ = 0x47;
 550         val = (ts_st->pid >> 8);
 551         if (is_start)
 552             val |= 0x40;
 553         *q++ = val;
 554         *q++ = ts_st->pid;
 555         *q++ = 0x10 | ts_st->cc | (write_pcr ? 0x20 : 0);
 556         ts_st->cc = (ts_st->cc + 1) & 0xf;
 557         if (write_pcr) {
 558             *q++ = 7; /* AFC length */
 559             *q++ = 0x10; /* flags: PCR present */
 560             *q++ = pcr >> 25;
 561             *q++ = pcr >> 17;
 562             *q++ = pcr >> 9;
 563             *q++ = pcr >> 1;
 564             *q++ = (pcr & 1) << 7;
 565             *q++ = 0;
 566         }
 567         if (is_start) {
 568             /* write PES header */
 569             *q++ = 0x00;
 570             *q++ = 0x00;
 571             *q++ = 0x01;
 572             private_code = 0;
 573             if (st->codec.codec_type == CODEC_TYPE_VIDEO) {
 574                 *q++ = 0xe0;
 575             } else if (st->codec.codec_type == CODEC_TYPE_AUDIO &&
 576                        (st->codec.codec_id == CODEC_ID_MP2 ||
 577                         st->codec.codec_id == CODEC_ID_MP3)) {
 578                 *q++ = 0xc0;
 579             } else {
 580                 *q++ = 0xbd;
 581                 if (st->codec.codec_type == CODEC_TYPE_SUBTITLE) {
 582                     private_code = 0x20;
 583                 }
 584             }
 585             if (pts != AV_NOPTS_VALUE)
 586                 header_len = 8;
 587             else
 588                 header_len = 3;
 589             if (private_code != 0)
 590                 header_len++;
 591             len = payload_size + header_len;
 592             *q++ = len >> 8;
 593             *q++ = len;
 594             val = 0x80;
 595             /* data alignment indicator is required for subtitle data */
 596             if (st->codec.codec_type == CODEC_TYPE_SUBTITLE)
 597                 val |= 0x04;
 598             *q++ = val;
 599             if (pts != AV_NOPTS_VALUE) {
 600                 *q++ = 0x80; /* PTS only */
 601                 *q++ = 0x05; /* header len */
 602                 val = (0x02 << 4) |
 603                     (((pts >> 30) & 0x07) << 1) | 1;
 604                 *q++ = val;
 605                 val = (((pts >> 15) & 0x7fff) << 1) | 1;
 606                 *q++ = val >> 8;
 607                 *q++ = val;
 608                 val = (((pts) & 0x7fff) << 1) | 1;
 609                 *q++ = val >> 8;
 610                 *q++ = val;
 611             } else {
 612                 *q++ = 0x00;
 613                 *q++ = 0x00;
 614             }
 615             if (private_code != 0)
 616                 *q++ = private_code;
 617             is_start = 0;
 618         }
 619         /* header size */
 620         header_len = q - buf;
 621         /* data len */
 622         len = TS_PACKET_SIZE - header_len;
 623         if (len > payload_size)
 624             len = payload_size;
 625         stuffing_len = TS_PACKET_SIZE - header_len - len;
 626         if (stuffing_len > 0) {
 627             /* add stuffing with AFC */
 628             if (buf[3] & 0x20) {
 629                 /* stuffing already present: increase its size */
 630                 afc_len = buf[4] + 1;
 631                 memmove(buf + 4 + afc_len + stuffing_len,
 632                         buf + 4 + afc_len,
 633                         header_len - (4 + afc_len));
 634                 buf[4] += stuffing_len;
 635                 memset(buf + 4 + afc_len, 0xff, stuffing_len);
 636             } else {
 637                 /* add stuffing */
 638                 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
 639                 buf[3] |= 0x20;
 640                 buf[4] = stuffing_len - 1;
 641                 if (stuffing_len >= 2) {
 642                     buf[5] = 0x00;
 643                     memset(buf + 6, 0xff, stuffing_len - 2);
 644                 }
 645             }
 646         }
 647         memcpy(buf + TS_PACKET_SIZE - len, payload, len);
 648         payload += len;
 649         payload_size -= len;
 650         put_buffer(&s->pb, buf, TS_PACKET_SIZE);
 651     }
 652     put_flush_packet(&s->pb);
 653 }
 654
 655 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
 656 {
 657     AVStream *st = s->streams[pkt->stream_index];
 658     int size= pkt->size;
 659     uint8_t *buf= pkt->data;
 660     MpegTSWriteStream *ts_st = st->priv_data;
 661     int len, max_payload_size;
 662
 663     if (st->codec.codec_type == CODEC_TYPE_SUBTITLE) {
 664         /* for subtitle, a single PES packet must be generated */
 665         mpegts_write_pes(s, st, buf, size, pkt->pts);
 666         return 0;
 667     }
 668
 669     max_payload_size = DEFAULT_PES_PAYLOAD_SIZE;
 670     while (size > 0) {
 671         len = max_payload_size - ts_st->payload_index;
 672         if (len > size)
 673             len = size;
 674         memcpy(ts_st->payload + ts_st->payload_index, buf, len);
 675         buf += len;
 676         size -= len;
 677         ts_st->payload_index += len;
 678         if (ts_st->payload_pts == AV_NOPTS_VALUE)
 679             ts_st->payload_pts = pkt->pts;
 680         if (ts_st->payload_index >= max_payload_size) {
 681             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
 682                              ts_st->payload_pts);
 683             ts_st->payload_pts = AV_NOPTS_VALUE;
 684             ts_st->payload_index = 0;
 685         }
 686     }
 687     return 0;
 688 }
 689
 690 static int mpegts_write_end(AVFormatContext *s)
 691 {
 692     MpegTSWrite *ts = s->priv_data;
 693     MpegTSWriteStream *ts_st;
 694     MpegTSService *service;
 695     AVStream *st;
 696     int i;
 697
 698     /* flush current packets */
 699     for(i = 0; i < s->nb_streams; i++) {
 700         st = s->streams[i];
 701         ts_st = st->priv_data;
 702         if (ts_st->payload_index > 0) {
 703             mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
 704                              ts_st->payload_pts);
 705         }
 706     }
 707     put_flush_packet(&s->pb);
 708
 709     for(i = 0; i < ts->nb_services; i++) {
 710         service = ts->services[i];
 711         av_freep(&service->provider_name);
 712         av_freep(&service->name);
 713         av_free(service);
 714     }
 715     av_free(ts->services);
 716
 717     return 0;
 718 }
 719
 720 AVOutputFormat mpegts_mux = {
 721     "mpegts",
 722     "MPEG2 transport stream format",
 723     "video/x-mpegts",
 724     "ts",
 725     sizeof(MpegTSWrite),
 726     CODEC_ID_MP2,
 727     CODEC_ID_MPEG2VIDEO,
 728     mpegts_write_header,
 729     mpegts_write_packet,
 730     mpegts_write_end,
 731 };