libavformat/mpegts.c

   1 /*
   2  * MPEG2 transport stream (aka DVB) demuxer
   3  * Copyright (c) 2002-2003 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 #include "avformat.h"
  22 #include "crc.h"
  23 #include "mpegts.h"
  24
  25 //#define DEBUG_SI
  26 //#define DEBUG_SEEK
  27
  28 /* 1.0 second at 24Mbit/s */
  29 #define MAX_SCAN_PACKETS 32000
  30
  31 /* maximum size in which we look for synchronisation if
  32    synchronisation is lost */
  33 #define MAX_RESYNC_SIZE 4096
  34
  35 typedef struct PESContext PESContext;
  36
  37 static PESContext* add_pes_stream(MpegTSContext *ts, int pid, int pcr_pid, int stream_type);
  38 static AVStream* new_pes_av_stream(PESContext *pes, uint32_t code);
  39 extern void av_set_program_name(AVProgram *program, char *provider_name, char *name);
  40 extern void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
  41
  42 enum MpegTSFilterType {
  43     MPEGTS_PES,
  44     MPEGTS_SECTION,
  45 };
  46
  47 typedef struct MpegTSFilter MpegTSFilter;
  48
  49 typedef void PESCallback(MpegTSFilter *f, const uint8_t *buf, int len, int is_start);
  50
  51 typedef struct MpegTSPESFilter {
  52     PESCallback *pes_cb;
  53     void *opaque;
  54 } MpegTSPESFilter;
  55
  56 typedef void SectionCallback(MpegTSFilter *f, const uint8_t *buf, int len);
  57
  58 typedef void SetServiceCallback(void *opaque, int ret);
  59
  60 typedef struct MpegTSSectionFilter {
  61     int section_index;
  62     int section_h_size;
  63     uint8_t *section_buf;
  64     int check_crc:1;
  65     int end_of_section_reached:1;
  66     SectionCallback *section_cb;
  67     void *opaque;
  68 } MpegTSSectionFilter;
  69
  70 struct MpegTSFilter {
  71     int pid;
  72     int last_cc; /* last cc code (-1 if first packet) */
  73     enum MpegTSFilterType type;
  74     union {
  75         MpegTSPESFilter pes_filter;
  76         MpegTSSectionFilter section_filter;
  77     } u;
  78 };
  79
  80 #define MAX_PIDS_PER_PROGRAM 64
  81 typedef struct {
  82     unsigned int id; //program id/service id
  83     unsigned int nb_pids;
  84     unsigned int pids[MAX_PIDS_PER_PROGRAM];
  85 } Program_t;
  86
  87 struct MpegTSContext {
  88     /* user data */
  89     AVFormatContext *stream;
  90     /** raw packet size, including FEC if present            */
  91     int raw_packet_size;
  92     /** if true, all pids are analyzed to find streams       */
  93     int auto_guess;
  94
  95     /** compute exact PCR for each transport stream packet   */
  96     int mpeg2ts_compute_pcr;
  97
  98     int64_t cur_pcr;    /**< used to estimate the exact PCR  */
  99     int pcr_incr;       /**< used to estimate the exact PCR  */
 100
 101     /* data needed to handle file based ts */
 102     /** stop parsing loop                                    */
 103     int stop_parse;
 104     /** packet containing Audio/Video data                   */
 105     AVPacket *pkt;
 106
 107     /******************************************/
 108     /* private mpegts data */
 109     /* scan context */
 110     /** structure to keep track of Program->pids mapping     */
 111     unsigned int nb_prg;
 112     Program_t *prg;
 113
 114
 115     /** filters for various streams specified by PMT + for the PAT and PMT */
 116     MpegTSFilter *pids[NB_PID_MAX];
 117 };
 118
 119 /* TS stream handling */
 120
 121 enum MpegTSState {
 122     MPEGTS_HEADER = 0,
 123     MPEGTS_PESHEADER_FILL,
 124     MPEGTS_PAYLOAD,
 125     MPEGTS_SKIP,
 126 };
 127
 128 /* enough for PES header + length */
 129 #define PES_START_SIZE 9
 130 #define MAX_PES_HEADER_SIZE (9 + 255)
 131
 132 struct PESContext {
 133     int pid;
 134     int pcr_pid; /**< if -1 then all packets containing PCR are considered */
 135     int stream_type;
 136     MpegTSContext *ts;
 137     AVFormatContext *stream;
 138     AVStream *st;
 139     enum MpegTSState state;
 140     /* used to get the format */
 141     int data_index;
 142     int total_size;
 143     int pes_header_size;
 144     int64_t pts, dts;
 145     uint8_t header[MAX_PES_HEADER_SIZE];
 146 };
 147
 148 extern AVInputFormat mpegts_demuxer;
 149
 150 static void clear_program(MpegTSContext *ts, unsigned int programid)
 151 {
 152     int i;
 153
 154     for(i=0; i<ts->nb_prg; i++)
 155         if(ts->prg[i].id == programid)
 156             ts->prg[i].nb_pids = 0;
 157 }
 158
 159 static void clear_programs(MpegTSContext *ts)
 160 {
 161     av_freep(&ts->prg);
 162     ts->nb_prg=0;
 163 }
 164
 165 static void add_pat_entry(MpegTSContext *ts, unsigned int programid)
 166 {
 167     Program_t *p;
 168     void *tmp = av_realloc(ts->prg, (ts->nb_prg+1)*sizeof(Program_t));
 169     if(!tmp)
 170         return;
 171     ts->prg = tmp;
 172     p = &ts->prg[ts->nb_prg];
 173     p->id = programid;
 174     p->nb_pids = 0;
 175     ts->nb_prg++;
 176 }
 177
 178 static void add_pid_to_pmt(MpegTSContext *ts, unsigned int programid, unsigned int pid)
 179 {
 180     int i;
 181     Program_t *p = NULL;
 182     for(i=0; i<ts->nb_prg; i++) {
 183         if(ts->prg[i].id == programid) {
 184             p = &ts->prg[i];
 185             break;
 186         }
 187     }
 188     if(!p)
 189         return;
 190
 191     if(p->nb_pids >= MAX_PIDS_PER_PROGRAM)
 192         return;
 193     p->pids[p->nb_pids++] = pid;
 194 }
 195
 196 /**
 197  * \brief discard_pid() decides if the pid is to be discarded according
 198  *                      to caller's programs selection
 199  * \param ts    : - TS context
 200  * \param pid   : - pid
 201  * \return 1 if the pid is only comprised in programs that have .discard=AVDISCARD_ALL
 202  *         0 otherwise
 203  */
 204 static int discard_pid(MpegTSContext *ts, unsigned int pid)
 205 {
 206     int i, j, k;
 207     int used = 0, discarded = 0;
 208     Program_t *p;
 209     for(i=0; i<ts->nb_prg; i++) {
 210         p = &ts->prg[i];
 211         for(j=0; j<p->nb_pids; j++) {
 212             if(p->pids[j] != pid)
 213                 continue;
 214             //is program with id p->id set to be discarded?
 215             for(k=0; k<ts->stream->nb_programs; k++) {
 216                 if(ts->stream->programs[k]->id == p->id) {
 217                     if(ts->stream->programs[k]->discard == AVDISCARD_ALL)
 218                         discarded++;
 219                     else
 220                         used++;
 221                 }
 222             }
 223         }
 224     }
 225
 226     return (!used && discarded);
 227 }
 228
 229 /**
 230  *  Assembles PES packets out of TS packets, and then calls the "section_cb"
 231  *  function when they are complete.
 232  */
 233 static void write_section_data(AVFormatContext *s, MpegTSFilter *tss1,
 234                                const uint8_t *buf, int buf_size, int is_start)
 235 {
 236     MpegTSSectionFilter *tss = &tss1->u.section_filter;
 237     int len;
 238
 239     if (is_start) {
 240         memcpy(tss->section_buf, buf, buf_size);
 241         tss->section_index = buf_size;
 242         tss->section_h_size = -1;
 243         tss->end_of_section_reached = 0;
 244     } else {
 245         if (tss->end_of_section_reached)
 246             return;
 247         len = 4096 - tss->section_index;
 248         if (buf_size < len)
 249             len = buf_size;
 250         memcpy(tss->section_buf + tss->section_index, buf, len);
 251         tss->section_index += len;
 252     }
 253
 254     /* compute section length if possible */
 255     if (tss->section_h_size == -1 && tss->section_index >= 3) {
 256         len = (AV_RB16(tss->section_buf + 1) & 0xfff) + 3;
 257         if (len > 4096)
 258             return;
 259         tss->section_h_size = len;
 260     }
 261
 262     if (tss->section_h_size != -1 && tss->section_index >= tss->section_h_size) {
 263         tss->end_of_section_reached = 1;
 264         if (!tss->check_crc ||
 265             av_crc(av_crc04C11DB7, -1, tss->section_buf, tss->section_h_size) == 0)
 266             tss->section_cb(tss1, tss->section_buf, tss->section_h_size);
 267     }
 268 }
 269
 270 static MpegTSFilter *mpegts_open_section_filter(MpegTSContext *ts, unsigned int pid,
 271                                          SectionCallback *section_cb, void *opaque,
 272                                          int check_crc)
 273
 274 {
 275     MpegTSFilter *filter;
 276     MpegTSSectionFilter *sec;
 277
 278 #ifdef DEBUG_SI
 279     av_log(ts->stream, AV_LOG_DEBUG, "Filter: pid=0x%x\n", pid);
 280 #endif
 281     if (pid >= NB_PID_MAX || ts->pids[pid])
 282         return NULL;
 283     filter = av_mallocz(sizeof(MpegTSFilter));
 284     if (!filter)
 285         return NULL;
 286     ts->pids[pid] = filter;
 287     filter->type = MPEGTS_SECTION;
 288     filter->pid = pid;
 289     filter->last_cc = -1;
 290     sec = &filter->u.section_filter;
 291     sec->section_cb = section_cb;
 292     sec->opaque = opaque;
 293     sec->section_buf = av_malloc(MAX_SECTION_SIZE);
 294     sec->check_crc = check_crc;
 295     if (!sec->section_buf) {
 296         av_free(filter);
 297         return NULL;
 298     }
 299     return filter;
 300 }
 301
 302 static MpegTSFilter *mpegts_open_pes_filter(MpegTSContext *ts, unsigned int pid,
 303                                      PESCallback *pes_cb,
 304                                      void *opaque)
 305 {
 306     MpegTSFilter *filter;
 307     MpegTSPESFilter *pes;
 308
 309     if (pid >= NB_PID_MAX || ts->pids[pid])
 310         return NULL;
 311     filter = av_mallocz(sizeof(MpegTSFilter));
 312     if (!filter)
 313         return NULL;
 314     ts->pids[pid] = filter;
 315     filter->type = MPEGTS_PES;
 316     filter->pid = pid;
 317     filter->last_cc = -1;
 318     pes = &filter->u.pes_filter;
 319     pes->pes_cb = pes_cb;
 320     pes->opaque = opaque;
 321     return filter;
 322 }
 323
 324 static void mpegts_close_filter(MpegTSContext *ts, MpegTSFilter *filter)
 325 {
 326     int pid;
 327
 328     pid = filter->pid;
 329     if (filter->type == MPEGTS_SECTION)
 330         av_freep(&filter->u.section_filter.section_buf);
 331     else if (filter->type == MPEGTS_PES)
 332         av_freep(&filter->u.pes_filter.opaque);
 333
 334     av_free(filter);
 335     ts->pids[pid] = NULL;
 336 }
 337
 338 static int analyze(const uint8_t *buf, int size, int packet_size, int *index){
 339     int stat[packet_size];
 340     int i;
 341     int x=0;
 342     int best_score=0;
 343
 344     memset(stat, 0, packet_size*sizeof(int));
 345
 346     for(x=i=0; i<size; i++){
 347         if(buf[i] == 0x47){
 348             stat[x]++;
 349             if(stat[x] > best_score){
 350                 best_score= stat[x];
 351                 if(index) *index= x;
 352             }
 353         }
 354
 355         x++;
 356         if(x == packet_size) x= 0;
 357     }
 358
 359     return best_score;
 360 }
 361
 362 /* autodetect fec presence. Must have at least 1024 bytes  */
 363 static int get_packet_size(const uint8_t *buf, int size)
 364 {
 365     int score, fec_score, dvhs_score;
 366
 367     if (size < (TS_FEC_PACKET_SIZE * 5 + 1))
 368         return -1;
 369
 370     score    = analyze(buf, size, TS_PACKET_SIZE, NULL);
 371     dvhs_score    = analyze(buf, size, TS_DVHS_PACKET_SIZE, NULL);
 372     fec_score= analyze(buf, size, TS_FEC_PACKET_SIZE, NULL);
 373 //    av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score);
 374
 375     if     (score > fec_score && score > dvhs_score) return TS_PACKET_SIZE;
 376     else if(dvhs_score > score && dvhs_score > fec_score) return TS_DVHS_PACKET_SIZE;
 377     else if(score < fec_score && dvhs_score < fec_score) return TS_FEC_PACKET_SIZE;
 378     else                       return -1;
 379 }
 380
 381 typedef struct SectionHeader {
 382     uint8_t tid;
 383     uint16_t id;
 384     uint8_t version;
 385     uint8_t sec_num;
 386     uint8_t last_sec_num;
 387 } SectionHeader;
 388
 389 static inline int get8(const uint8_t **pp, const uint8_t *p_end)
 390 {
 391     const uint8_t *p;
 392     int c;
 393
 394     p = *pp;
 395     if (p >= p_end)
 396         return -1;
 397     c = *p++;
 398     *pp = p;
 399     return c;
 400 }
 401
 402 static inline int get16(const uint8_t **pp, const uint8_t *p_end)
 403 {
 404     const uint8_t *p;
 405     int c;
 406
 407     p = *pp;
 408     if ((p + 1) >= p_end)
 409         return -1;
 410     c = AV_RB16(p);
 411     p += 2;
 412     *pp = p;
 413     return c;
 414 }
 415
 416 /* read and allocate a DVB string preceeded by its length */
 417 static char *getstr8(const uint8_t **pp, const uint8_t *p_end)
 418 {
 419     int len;
 420     const uint8_t *p;
 421     char *str;
 422
 423     p = *pp;
 424     len = get8(&p, p_end);
 425     if (len < 0)
 426         return NULL;
 427     if ((p + len) > p_end)
 428         return NULL;
 429     str = av_malloc(len + 1);
 430     if (!str)
 431         return NULL;
 432     memcpy(str, p, len);
 433     str[len] = '\0';
 434     p += len;
 435     *pp = p;
 436     return str;
 437 }
 438
 439 static int parse_section_header(SectionHeader *h,
 440                                 const uint8_t **pp, const uint8_t *p_end)
 441 {
 442     int val;
 443
 444     val = get8(pp, p_end);
 445     if (val < 0)
 446         return -1;
 447     h->tid = val;
 448     *pp += 2;
 449     val = get16(pp, p_end);
 450     if (val < 0)
 451         return -1;
 452     h->id = val;
 453     val = get8(pp, p_end);
 454     if (val < 0)
 455         return -1;
 456     h->version = (val >> 1) & 0x1f;
 457     val = get8(pp, p_end);
 458     if (val < 0)
 459         return -1;
 460     h->sec_num = val;
 461     val = get8(pp, p_end);
 462     if (val < 0)
 463         return -1;
 464     h->last_sec_num = val;
 465     return 0;
 466 }
 467
 468
 469 static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
 470 {
 471     MpegTSContext *ts = filter->u.section_filter.opaque;
 472     SectionHeader h1, *h = &h1;
 473     PESContext *pes;
 474     AVStream *st;
 475     const uint8_t *p, *p_end, *desc_list_end, *desc_end;
 476     int program_info_length, pcr_pid, pid, stream_type;
 477     int desc_list_len, desc_len, desc_tag;
 478     int comp_page = 0, anc_page = 0; /* initialize to kill warnings */
 479     char language[4] = {0}; /* initialize to kill warnings */
 480
 481 #ifdef DEBUG_SI
 482     av_log(ts->stream, AV_LOG_DEBUG, "PMT: len %i\n", section_len);
 483     av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len);
 484 #endif
 485     p_end = section + section_len - 4;
 486     p = section;
 487     if (parse_section_header(h, &p, p_end) < 0)
 488         return;
 489 #ifdef DEBUG_SI
 490     av_log(ts->stream, AV_LOG_DEBUG, "sid=0x%x sec_num=%d/%d\n",
 491            h->id, h->sec_num, h->last_sec_num);
 492 #endif
 493     if (h->tid != PMT_TID)
 494         return;
 495
 496     clear_program(ts, h->id);
 497     pcr_pid = get16(&p, p_end) & 0x1fff;
 498     if (pcr_pid < 0)
 499         return;
 500     add_pid_to_pmt(ts, h->id, pcr_pid);
 501 #ifdef DEBUG_SI
 502     av_log(ts->stream, AV_LOG_DEBUG, "pcr_pid=0x%x\n", pcr_pid);
 503 #endif
 504     program_info_length = get16(&p, p_end) & 0xfff;
 505     if (program_info_length < 0)
 506         return;
 507     p += program_info_length;
 508     if (p >= p_end)
 509         return;
 510     for(;;) {
 511         language[0] = 0;
 512         st = 0;
 513         stream_type = get8(&p, p_end);
 514         if (stream_type < 0)
 515             break;
 516         pid = get16(&p, p_end) & 0x1fff;
 517         if (pid < 0)
 518             break;
 519         desc_list_len = get16(&p, p_end) & 0xfff;
 520         if (desc_list_len < 0)
 521             break;
 522         desc_list_end = p + desc_list_len;
 523         if (desc_list_end > p_end)
 524             break;
 525         for(;;) {
 526             desc_tag = get8(&p, desc_list_end);
 527             if (desc_tag < 0)
 528                 break;
 529             if (stream_type == STREAM_TYPE_PRIVATE_DATA) {
 530                 if((desc_tag == 0x6A) || (desc_tag == 0x7A)) {
 531                     /*assume DVB AC-3 Audio*/
 532                     stream_type = STREAM_TYPE_AUDIO_AC3;
 533                 } else if(desc_tag == 0x7B) {
 534                     /* DVB DTS audio */
 535                     stream_type = STREAM_TYPE_AUDIO_DTS;
 536                 }
 537             }
 538             desc_len = get8(&p, desc_list_end);
 539             desc_end = p + desc_len;
 540             if (desc_end > desc_list_end)
 541                 break;
 542 #ifdef DEBUG_SI
 543             av_log(ts->stream, AV_LOG_DEBUG, "tag: 0x%02x len=%d\n",
 544                    desc_tag, desc_len);
 545 #endif
 546             switch(desc_tag) {
 547             case DVB_SUBT_DESCID:
 548                 if (stream_type == STREAM_TYPE_PRIVATE_DATA)
 549                     stream_type = STREAM_TYPE_SUBTITLE_DVB;
 550
 551                 language[0] = get8(&p, desc_end);
 552                 language[1] = get8(&p, desc_end);
 553                 language[2] = get8(&p, desc_end);
 554                 language[3] = 0;
 555                 get8(&p, desc_end);
 556                 comp_page = get16(&p, desc_end);
 557                 anc_page = get16(&p, desc_end);
 558
 559                 break;
 560             case 0x0a: /* ISO 639 language descriptor */
 561                 language[0] = get8(&p, desc_end);
 562                 language[1] = get8(&p, desc_end);
 563                 language[2] = get8(&p, desc_end);
 564                 language[3] = 0;
 565                 break;
 566             default:
 567                 break;
 568             }
 569             p = desc_end;
 570         }
 571         p = desc_list_end;
 572
 573 #ifdef DEBUG_SI
 574         av_log(ts->stream, AV_LOG_DEBUG, "stream_type=%d pid=0x%x\n",
 575                stream_type, pid);
 576 #endif
 577
 578         /* now create ffmpeg stream */
 579         switch(stream_type) {
 580         case STREAM_TYPE_AUDIO_MPEG1:
 581         case STREAM_TYPE_AUDIO_MPEG2:
 582         case STREAM_TYPE_VIDEO_MPEG1:
 583         case STREAM_TYPE_VIDEO_MPEG2:
 584         case STREAM_TYPE_VIDEO_MPEG4:
 585         case STREAM_TYPE_VIDEO_H264:
 586         case STREAM_TYPE_VIDEO_VC1:
 587         case STREAM_TYPE_AUDIO_AAC:
 588         case STREAM_TYPE_AUDIO_AC3:
 589         case STREAM_TYPE_AUDIO_DTS:
 590         case STREAM_TYPE_SUBTITLE_DVB:
 591             if(ts->pids[pid] && ts->pids[pid]->type == MPEGTS_PES){
 592                 pes= ts->pids[pid]->u.pes_filter.opaque;
 593                 st= pes->st;
 594             }else{
 595                 if (ts->pids[pid]) mpegts_close_filter(ts, ts->pids[pid]); //wrongly added sdt filter probably
 596                 pes = add_pes_stream(ts, pid, pcr_pid, stream_type);
 597                 if (pes)
 598                     st = new_pes_av_stream(pes, 0);
 599             }
 600             add_pid_to_pmt(ts, h->id, pid);
 601             if(st)
 602                 av_program_add_stream_index(ts->stream, h->id, st->index);
 603             break;
 604         default:
 605             /* we ignore the other streams */
 606             break;
 607         }
 608
 609         if (st) {
 610             if (language[0] != 0) {
 611                 memcpy(st->language, language, 4);
 612             }
 613
 614             if (stream_type == STREAM_TYPE_SUBTITLE_DVB) {
 615                 st->codec->sub_id = (anc_page << 16) | comp_page;
 616             }
 617         }
 618     }
 619     /* all parameters are there */
 620     ts->stop_parse++;
 621     mpegts_close_filter(ts, filter);
 622 }
 623
 624 static void pat_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
 625 {
 626     MpegTSContext *ts = filter->u.section_filter.opaque;
 627     SectionHeader h1, *h = &h1;
 628     const uint8_t *p, *p_end;
 629     int sid, pmt_pid;
 630
 631 #ifdef DEBUG_SI
 632     av_log(ts->stream, AV_LOG_DEBUG, "PAT:\n");
 633     av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len);
 634 #endif
 635     p_end = section + section_len - 4;
 636     p = section;
 637     if (parse_section_header(h, &p, p_end) < 0)
 638         return;
 639     if (h->tid != PAT_TID)
 640         return;
 641
 642     clear_programs(ts);
 643     for(;;) {
 644         sid = get16(&p, p_end);
 645         if (sid < 0)
 646             break;
 647         pmt_pid = get16(&p, p_end) & 0x1fff;
 648         if (pmt_pid < 0)
 649             break;
 650 #ifdef DEBUG_SI
 651         av_log(ts->stream, AV_LOG_DEBUG, "sid=0x%x pid=0x%x\n", sid, pmt_pid);
 652 #endif
 653         if (sid == 0x0000) {
 654             /* NIT info */
 655         } else {
 656             av_new_program(ts->stream, sid);
 657             ts->stop_parse--;
 658             mpegts_open_section_filter(ts, pmt_pid, pmt_cb, ts, 1);
 659             add_pat_entry(ts, sid);
 660             add_pid_to_pmt(ts, sid, 0); //add pat pid to program
 661             add_pid_to_pmt(ts, sid, pmt_pid);
 662         }
 663     }
 664     /* not found */
 665     ts->stop_parse++;
 666
 667     mpegts_close_filter(ts, filter);
 668 }
 669
 670 static void mpegts_set_service(MpegTSContext *ts)
 671 {
 672     mpegts_open_section_filter(ts, PAT_PID,
 673                                                 pat_cb, ts, 1);
 674 }
 675
 676 static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
 677 {
 678     MpegTSContext *ts = filter->u.section_filter.opaque;
 679     SectionHeader h1, *h = &h1;
 680     const uint8_t *p, *p_end, *desc_list_end, *desc_end;
 681     int onid, val, sid, desc_list_len, desc_tag, desc_len, service_type;
 682     char *name, *provider_name;
 683
 684 #ifdef DEBUG_SI
 685     av_log(ts->stream, AV_LOG_DEBUG, "SDT:\n");
 686     av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len);
 687 #endif
 688
 689     p_end = section + section_len - 4;
 690     p = section;
 691     if (parse_section_header(h, &p, p_end) < 0)
 692         return;
 693     if (h->tid != SDT_TID)
 694         return;
 695     onid = get16(&p, p_end);
 696     if (onid < 0)
 697         return;
 698     val = get8(&p, p_end);
 699     if (val < 0)
 700         return;
 701     for(;;) {
 702         sid = get16(&p, p_end);
 703         if (sid < 0)
 704             break;
 705         val = get8(&p, p_end);
 706         if (val < 0)
 707             break;
 708         desc_list_len = get16(&p, p_end) & 0xfff;
 709         if (desc_list_len < 0)
 710             break;
 711         desc_list_end = p + desc_list_len;
 712         if (desc_list_end > p_end)
 713             break;
 714         for(;;) {
 715             desc_tag = get8(&p, desc_list_end);
 716             if (desc_tag < 0)
 717                 break;
 718             desc_len = get8(&p, desc_list_end);
 719             desc_end = p + desc_len;
 720             if (desc_end > desc_list_end)
 721                 break;
 722 #ifdef DEBUG_SI
 723             av_log(ts->stream, AV_LOG_DEBUG, "tag: 0x%02x len=%d\n",
 724                    desc_tag, desc_len);
 725 #endif
 726             switch(desc_tag) {
 727             case 0x48:
 728                 service_type = get8(&p, p_end);
 729                 if (service_type < 0)
 730                     break;
 731                 provider_name = getstr8(&p, p_end);
 732                 if (!provider_name)
 733                     break;
 734                 name = getstr8(&p, p_end);
 735                 if (name) {
 736                     AVProgram *program = av_new_program(ts->stream, sid);
 737                     if(program)
 738                         av_set_program_name(program, provider_name, name);
 739                 }
 740                 break;
 741             default:
 742                 break;
 743             }
 744             p = desc_end;
 745         }
 746         p = desc_list_end;
 747     }
 748 }
 749
 750 /* scan services in a transport stream by looking at the SDT */
 751 static void mpegts_scan_sdt(MpegTSContext *ts)
 752 {
 753     mpegts_open_section_filter(ts, SDT_PID,
 754                                                 sdt_cb, ts, 1);
 755 }
 756
 757 static int64_t get_pts(const uint8_t *p)
 758 {
 759     int64_t pts = (int64_t)((p[0] >> 1) & 0x07) << 30;
 760     pts |= (AV_RB16(p + 1) >> 1) << 15;
 761     pts |=  AV_RB16(p + 3) >> 1;
 762     return pts;
 763 }
 764
 765 /* return non zero if a packet could be constructed */
 766 static void mpegts_push_data(MpegTSFilter *filter,
 767                              const uint8_t *buf, int buf_size, int is_start)
 768 {
 769     PESContext *pes = filter->u.pes_filter.opaque;
 770     MpegTSContext *ts = pes->ts;
 771     const uint8_t *p;
 772     int len, code;
 773
 774     if(!ts->pkt)
 775         return;
 776
 777     if (is_start) {
 778         pes->state = MPEGTS_HEADER;
 779         pes->data_index = 0;
 780     }
 781     p = buf;
 782     while (buf_size > 0) {
 783         switch(pes->state) {
 784         case MPEGTS_HEADER:
 785             len = PES_START_SIZE - pes->data_index;
 786             if (len > buf_size)
 787                 len = buf_size;
 788             memcpy(pes->header + pes->data_index, p, len);
 789             pes->data_index += len;
 790             p += len;
 791             buf_size -= len;
 792             if (pes->data_index == PES_START_SIZE) {
 793                 /* we got all the PES or section header. We can now
 794                    decide */
 795 #if 0
 796                 av_hex_dump_log(pes->stream, AV_LOG_DEBUG, pes->header, pes->data_index);
 797 #endif
 798                 if (pes->header[0] == 0x00 && pes->header[1] == 0x00 &&
 799                     pes->header[2] == 0x01) {
 800                     /* it must be an mpeg2 PES stream */
 801                     code = pes->header[3] | 0x100;
 802                     if (!((code >= 0x1c0 && code <= 0x1df) ||
 803                           (code >= 0x1e0 && code <= 0x1ef) ||
 804                           (code == 0x1bd) || (code == 0x1fd)))
 805                         goto skip;
 806                     if (!pes->st) {
 807                         /* allocate stream */
 808                         new_pes_av_stream(pes, code);
 809                     }
 810                     pes->state = MPEGTS_PESHEADER_FILL;
 811                     pes->total_size = AV_RB16(pes->header + 4);
 812                     /* NOTE: a zero total size means the PES size is
 813                        unbounded */
 814                     if (pes->total_size)
 815                         pes->total_size += 6;
 816                     pes->pes_header_size = pes->header[8] + 9;
 817                 } else {
 818                     /* otherwise, it should be a table */
 819                     /* skip packet */
 820                 skip:
 821                     pes->state = MPEGTS_SKIP;
 822                     continue;
 823                 }
 824             }
 825             break;
 826             /**********************************************/
 827             /* PES packing parsing */
 828         case MPEGTS_PESHEADER_FILL:
 829             len = pes->pes_header_size - pes->data_index;
 830             if (len > buf_size)
 831                 len = buf_size;
 832             memcpy(pes->header + pes->data_index, p, len);
 833             pes->data_index += len;
 834             p += len;
 835             buf_size -= len;
 836             if (pes->data_index == pes->pes_header_size) {
 837                 const uint8_t *r;
 838                 unsigned int flags;
 839
 840                 flags = pes->header[7];
 841                 r = pes->header + 9;
 842                 pes->pts = AV_NOPTS_VALUE;
 843                 pes->dts = AV_NOPTS_VALUE;
 844                 if ((flags & 0xc0) == 0x80) {
 845                     pes->pts = get_pts(r);
 846                     r += 5;
 847                 } else if ((flags & 0xc0) == 0xc0) {
 848                     pes->pts = get_pts(r);
 849                     r += 5;
 850                     pes->dts = get_pts(r);
 851                     r += 5;
 852                 }
 853                 /* we got the full header. We parse it and get the payload */
 854                 pes->state = MPEGTS_PAYLOAD;
 855             }
 856             break;
 857         case MPEGTS_PAYLOAD:
 858             if (pes->total_size) {
 859                 len = pes->total_size - pes->data_index;
 860                 if (len > buf_size)
 861                     len = buf_size;
 862             } else {
 863                 len = buf_size;
 864             }
 865             if (len > 0) {
 866                 AVPacket *pkt = ts->pkt;
 867                 if (pes->st && av_new_packet(pkt, len) == 0) {
 868                     memcpy(pkt->data, p, len);
 869                     pkt->stream_index = pes->st->index;
 870                     pkt->pts = pes->pts;
 871                     pkt->dts = pes->dts;
 872                     /* reset pts values */
 873                     pes->pts = AV_NOPTS_VALUE;
 874                     pes->dts = AV_NOPTS_VALUE;
 875                     ts->stop_parse = 1;
 876                     return;
 877                 }
 878             }
 879             buf_size = 0;
 880             break;
 881         case MPEGTS_SKIP:
 882             buf_size = 0;
 883             break;
 884         }
 885     }
 886 }
 887
 888 static AVStream* new_pes_av_stream(PESContext *pes, uint32_t code)
 889 {
 890     AVStream *st;
 891     int codec_type, codec_id;
 892
 893     switch(pes->stream_type){
 894     case STREAM_TYPE_AUDIO_MPEG1:
 895     case STREAM_TYPE_AUDIO_MPEG2:
 896         codec_type = CODEC_TYPE_AUDIO;
 897         codec_id = CODEC_ID_MP3;
 898         break;
 899     case STREAM_TYPE_VIDEO_MPEG1:
 900     case STREAM_TYPE_VIDEO_MPEG2:
 901         codec_type = CODEC_TYPE_VIDEO;
 902         codec_id = CODEC_ID_MPEG2VIDEO;
 903         break;
 904     case STREAM_TYPE_VIDEO_MPEG4:
 905         codec_type = CODEC_TYPE_VIDEO;
 906         codec_id = CODEC_ID_MPEG4;
 907         break;
 908     case STREAM_TYPE_VIDEO_H264:
 909         codec_type = CODEC_TYPE_VIDEO;
 910         codec_id = CODEC_ID_H264;
 911         break;
 912     case STREAM_TYPE_VIDEO_VC1:
 913         codec_type = CODEC_TYPE_VIDEO;
 914         codec_id = CODEC_ID_VC1;
 915         break;
 916     case STREAM_TYPE_AUDIO_AAC:
 917         codec_type = CODEC_TYPE_AUDIO;
 918         codec_id = CODEC_ID_AAC;
 919         break;
 920     case STREAM_TYPE_AUDIO_AC3:
 921         codec_type = CODEC_TYPE_AUDIO;
 922         codec_id = CODEC_ID_AC3;
 923         break;
 924     case STREAM_TYPE_AUDIO_DTS:
 925         codec_type = CODEC_TYPE_AUDIO;
 926         codec_id = CODEC_ID_DTS;
 927         break;
 928     case STREAM_TYPE_SUBTITLE_DVB:
 929         codec_type = CODEC_TYPE_SUBTITLE;
 930         codec_id = CODEC_ID_DVB_SUBTITLE;
 931         break;
 932     default:
 933         if (code >= 0x1c0 && code <= 0x1df) {
 934             codec_type = CODEC_TYPE_AUDIO;
 935             codec_id = CODEC_ID_MP2;
 936         } else if (code == 0x1bd) {
 937             codec_type = CODEC_TYPE_AUDIO;
 938             codec_id = CODEC_ID_AC3;
 939         } else {
 940             codec_type = CODEC_TYPE_VIDEO;
 941             codec_id = CODEC_ID_MPEG1VIDEO;
 942         }
 943         break;
 944     }
 945     st = av_new_stream(pes->stream, pes->pid);
 946     if (st) {
 947         av_set_pts_info(st, 33, 1, 90000);
 948         st->priv_data = pes;
 949         st->codec->codec_type = codec_type;
 950         st->codec->codec_id = codec_id;
 951         st->need_parsing = AVSTREAM_PARSE_FULL;
 952         pes->st = st;
 953     }
 954     return st;
 955 }
 956
 957
 958 static PESContext *add_pes_stream(MpegTSContext *ts, int pid, int pcr_pid, int stream_type)
 959 {
 960     MpegTSFilter *tss;
 961     PESContext *pes;
 962
 963     /* if no pid found, then add a pid context */
 964     pes = av_mallocz(sizeof(PESContext));
 965     if (!pes)
 966         return 0;
 967     pes->ts = ts;
 968     pes->stream = ts->stream;
 969     pes->pid = pid;
 970     pes->pcr_pid = pcr_pid;
 971     pes->stream_type = stream_type;
 972     tss = mpegts_open_pes_filter(ts, pid, mpegts_push_data, pes);
 973     if (!tss) {
 974         av_free(pes);
 975         return 0;
 976     }
 977     return pes;
 978 }
 979
 980 /* handle one TS packet */
 981 static void handle_packet(MpegTSContext *ts, const uint8_t *packet)
 982 {
 983     AVFormatContext *s = ts->stream;
 984     MpegTSFilter *tss;
 985     int len, pid, cc, cc_ok, afc, is_start;
 986     const uint8_t *p, *p_end;
 987
 988     pid = AV_RB16(packet + 1) & 0x1fff;
 989     if(pid && discard_pid(ts, pid))
 990         return;
 991     is_start = packet[1] & 0x40;
 992     tss = ts->pids[pid];
 993     if (ts->auto_guess && tss == NULL && is_start) {
 994         add_pes_stream(ts, pid, -1, 0);
 995         tss = ts->pids[pid];
 996     }
 997     if (!tss)
 998         return;
 999
1000     /* continuity check (currently not used) */
1001     cc = (packet[3] & 0xf);
1002     cc_ok = (tss->last_cc < 0) || ((((tss->last_cc + 1) & 0x0f) == cc));
1003     tss->last_cc = cc;
1004
1005     /* skip adaptation field */
1006     afc = (packet[3] >> 4) & 3;
1007     p = packet + 4;
1008     if (afc == 0) /* reserved value */
1009         return;
1010     if (afc == 2) /* adaptation field only */
1011         return;
1012     if (afc == 3) {
1013         /* skip adapation field */
1014         p += p[0] + 1;
1015     }
1016     /* if past the end of packet, ignore */
1017     p_end = packet + TS_PACKET_SIZE;
1018     if (p >= p_end)
1019         return;
1020
1021     if (tss->type == MPEGTS_SECTION) {
1022         if (is_start) {
1023             /* pointer field present */
1024             len = *p++;
1025             if (p + len > p_end)
1026                 return;
1027             if (len && cc_ok) {
1028                 /* write remaining section bytes */
1029                 write_section_data(s, tss,
1030                                    p, len, 0);
1031                 /* check whether filter has been closed */
1032                 if (!ts->pids[pid])
1033                     return;
1034             }
1035             p += len;
1036             if (p < p_end) {
1037                 write_section_data(s, tss,
1038                                    p, p_end - p, 1);
1039             }
1040         } else {
1041             if (cc_ok) {
1042                 write_section_data(s, tss,
1043                                    p, p_end - p, 0);
1044             }
1045         }
1046     } else {
1047         tss->u.pes_filter.pes_cb(tss,
1048                                  p, p_end - p, is_start);
1049     }
1050 }
1051
1052 /* XXX: try to find a better synchro over several packets (use
1053    get_packet_size() ?) */
1054 static int mpegts_resync(ByteIOContext *pb)
1055 {
1056     int c, i;
1057
1058     for(i = 0;i < MAX_RESYNC_SIZE; i++) {
1059         c = url_fgetc(pb);
1060         if (c < 0)
1061             return -1;
1062         if (c == 0x47) {
1063             url_fseek(pb, -1, SEEK_CUR);
1064             return 0;
1065         }
1066     }
1067     /* no sync found */
1068     return -1;
1069 }
1070
1071 /* return -1 if error or EOF. Return 0 if OK. */
1072 static int read_packet(ByteIOContext *pb, uint8_t *buf, int raw_packet_size)
1073 {
1074     int skip, len;
1075
1076     for(;;) {
1077         len = get_buffer(pb, buf, TS_PACKET_SIZE);
1078         if (len != TS_PACKET_SIZE)
1079             return AVERROR(EIO);
1080         /* check paquet sync byte */
1081         if (buf[0] != 0x47) {
1082             /* find a new packet start */
1083             url_fseek(pb, -TS_PACKET_SIZE, SEEK_CUR);
1084             if (mpegts_resync(pb) < 0)
1085                 return AVERROR_INVALIDDATA;
1086             else
1087                 continue;
1088         } else {
1089             skip = raw_packet_size - TS_PACKET_SIZE;
1090             if (skip > 0)
1091                 url_fskip(pb, skip);
1092             break;
1093         }
1094     }
1095     return 0;
1096 }
1097
1098 static int handle_packets(MpegTSContext *ts, int nb_packets)
1099 {
1100     AVFormatContext *s = ts->stream;
1101     ByteIOContext *pb = &s->pb;
1102     uint8_t packet[TS_PACKET_SIZE];
1103     int packet_num, ret;
1104
1105     ts->stop_parse = 0;
1106     packet_num = 0;
1107     for(;;) {
1108         if (ts->stop_parse>0)
1109             break;
1110         packet_num++;
1111         if (nb_packets != 0 && packet_num >= nb_packets)
1112             break;
1113         ret = read_packet(pb, packet, ts->raw_packet_size);
1114         if (ret != 0)
1115             return ret;
1116         handle_packet(ts, packet);
1117     }
1118     return 0;
1119 }
1120
1121 static int mpegts_probe(AVProbeData *p)
1122 {
1123 #if 1
1124     const int size= p->buf_size;
1125     int score, fec_score, dvhs_score;
1126 #define CHECK_COUNT 10
1127
1128     if (size < (TS_FEC_PACKET_SIZE * CHECK_COUNT))
1129         return -1;
1130
1131     score    = analyze(p->buf, TS_PACKET_SIZE    *CHECK_COUNT, TS_PACKET_SIZE, NULL);
1132     dvhs_score  = analyze(p->buf, TS_DVHS_PACKET_SIZE    *CHECK_COUNT, TS_DVHS_PACKET_SIZE, NULL);
1133     fec_score= analyze(p->buf, TS_FEC_PACKET_SIZE*CHECK_COUNT, TS_FEC_PACKET_SIZE, NULL);
1134 //    av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score);
1135
1136 // we need a clear definition for the returned score otherwise things will become messy sooner or later
1137     if     (score > fec_score && score > dvhs_score && score > 6) return AVPROBE_SCORE_MAX + score     - CHECK_COUNT;
1138     else if(dvhs_score > score && dvhs_score > fec_score && dvhs_score > 6) return AVPROBE_SCORE_MAX + dvhs_score  - CHECK_COUNT;
1139     else if(                 fec_score > 6) return AVPROBE_SCORE_MAX + fec_score - CHECK_COUNT;
1140     else                                    return -1;
1141 #else
1142     /* only use the extension for safer guess */
1143     if (match_ext(p->filename, "ts"))
1144         return AVPROBE_SCORE_MAX;
1145     else
1146         return 0;
1147 #endif
1148 }
1149
1150 /* return the 90 kHz PCR and the extension for the 27 MHz PCR. return
1151    (-1) if not available */
1152 static int parse_pcr(int64_t *ppcr_high, int *ppcr_low,
1153                      const uint8_t *packet)
1154 {
1155     int afc, len, flags;
1156     const uint8_t *p;
1157     unsigned int v;
1158
1159     afc = (packet[3] >> 4) & 3;
1160     if (afc <= 1)
1161         return -1;
1162     p = packet + 4;
1163     len = p[0];
1164     p++;
1165     if (len == 0)
1166         return -1;
1167     flags = *p++;
1168     len--;
1169     if (!(flags & 0x10))
1170         return -1;
1171     if (len < 6)
1172         return -1;
1173     v = AV_RB32(p);
1174     *ppcr_high = ((int64_t)v << 1) | (p[4] >> 7);
1175     *ppcr_low = ((p[4] & 1) << 8) | p[5];
1176     return 0;
1177 }
1178
1179 static int mpegts_read_header(AVFormatContext *s,
1180                               AVFormatParameters *ap)
1181 {
1182     MpegTSContext *ts = s->priv_data;
1183     ByteIOContext *pb = &s->pb;
1184     uint8_t buf[1024];
1185     int len;
1186     int64_t pos;
1187
1188     if (ap) {
1189         ts->mpeg2ts_compute_pcr = ap->mpeg2ts_compute_pcr;
1190         if(ap->mpeg2ts_raw){
1191             av_log(s, AV_LOG_ERROR, "use mpegtsraw_demuxer!\n");
1192             return -1;
1193         }
1194     }
1195
1196     /* read the first 1024 bytes to get packet size */
1197     pos = url_ftell(pb);
1198     len = get_buffer(pb, buf, sizeof(buf));
1199     if (len != sizeof(buf))
1200         goto fail;
1201     ts->raw_packet_size = get_packet_size(buf, sizeof(buf));
1202     if (ts->raw_packet_size <= 0)
1203         goto fail;
1204     ts->stream = s;
1205     ts->auto_guess = 0;
1206
1207     if (s->iformat == &mpegts_demuxer) {
1208         /* normal demux */
1209
1210         /* first do a scaning to get all the services */
1211         url_fseek(pb, pos, SEEK_SET);
1212         mpegts_scan_sdt(ts);
1213
1214         mpegts_set_service(ts);
1215
1216         handle_packets(ts, s->probesize);
1217         /* if could not find service, enable auto_guess */
1218
1219         ts->auto_guess = 1;
1220
1221 #ifdef DEBUG_SI
1222         av_log(ts->stream, AV_LOG_DEBUG, "tuning done\n");
1223 #endif
1224         s->ctx_flags |= AVFMTCTX_NOHEADER;
1225     } else {
1226         AVStream *st;
1227         int pcr_pid, pid, nb_packets, nb_pcrs, ret, pcr_l;
1228         int64_t pcrs[2], pcr_h;
1229         int packet_count[2];
1230         uint8_t packet[TS_PACKET_SIZE];
1231
1232         /* only read packets */
1233
1234         st = av_new_stream(s, 0);
1235         if (!st)
1236             goto fail;
1237         av_set_pts_info(st, 60, 1, 27000000);
1238         st->codec->codec_type = CODEC_TYPE_DATA;
1239         st->codec->codec_id = CODEC_ID_MPEG2TS;
1240
1241         /* we iterate until we find two PCRs to estimate the bitrate */
1242         pcr_pid = -1;
1243         nb_pcrs = 0;
1244         nb_packets = 0;
1245         for(;;) {
1246             ret = read_packet(&s->pb, packet, ts->raw_packet_size);
1247             if (ret < 0)
1248                 return -1;
1249             pid = AV_RB16(packet + 1) & 0x1fff;
1250             if ((pcr_pid == -1 || pcr_pid == pid) &&
1251                 parse_pcr(&pcr_h, &pcr_l, packet) == 0) {
1252                 pcr_pid = pid;
1253                 packet_count[nb_pcrs] = nb_packets;
1254                 pcrs[nb_pcrs] = pcr_h * 300 + pcr_l;
1255                 nb_pcrs++;
1256                 if (nb_pcrs >= 2)
1257                     break;
1258             }
1259             nb_packets++;
1260         }
1261
1262         /* NOTE1: the bitrate is computed without the FEC */
1263         /* NOTE2: it is only the bitrate of the start of the stream */
1264         ts->pcr_incr = (pcrs[1] - pcrs[0]) / (packet_count[1] - packet_count[0]);
1265         ts->cur_pcr = pcrs[0] - ts->pcr_incr * packet_count[0];
1266         s->bit_rate = (TS_PACKET_SIZE * 8) * 27e6 / ts->pcr_incr;
1267         st->codec->bit_rate = s->bit_rate;
1268         st->start_time = ts->cur_pcr;
1269 #if 0
1270         av_log(ts->stream, AV_LOG_DEBUG, "start=%0.3f pcr=%0.3f incr=%d\n",
1271                st->start_time / 1000000.0, pcrs[0] / 27e6, ts->pcr_incr);
1272 #endif
1273     }
1274
1275     url_fseek(pb, pos, SEEK_SET);
1276     return 0;
1277  fail:
1278     return -1;
1279 }
1280
1281 #define MAX_PACKET_READAHEAD ((128 * 1024) / 188)
1282
1283 static int mpegts_raw_read_packet(AVFormatContext *s,
1284                                   AVPacket *pkt)
1285 {
1286     MpegTSContext *ts = s->priv_data;
1287     int ret, i;
1288     int64_t pcr_h, next_pcr_h, pos;
1289     int pcr_l, next_pcr_l;
1290     uint8_t pcr_buf[12];
1291
1292     if (av_new_packet(pkt, TS_PACKET_SIZE) < 0)
1293         return AVERROR(ENOMEM);
1294     pkt->pos= url_ftell(&s->pb);
1295     ret = read_packet(&s->pb, pkt->data, ts->raw_packet_size);
1296     if (ret < 0) {
1297         av_free_packet(pkt);
1298         return ret;
1299     }
1300     if (ts->mpeg2ts_compute_pcr) {
1301         /* compute exact PCR for each packet */
1302         if (parse_pcr(&pcr_h, &pcr_l, pkt->data) == 0) {
1303             /* we read the next PCR (XXX: optimize it by using a bigger buffer */
1304             pos = url_ftell(&s->pb);
1305             for(i = 0; i < MAX_PACKET_READAHEAD; i++) {
1306                 url_fseek(&s->pb, pos + i * ts->raw_packet_size, SEEK_SET);
1307                 get_buffer(&s->pb, pcr_buf, 12);
1308                 if (parse_pcr(&next_pcr_h, &next_pcr_l, pcr_buf) == 0) {
1309                     /* XXX: not precise enough */
1310                     ts->pcr_incr = ((next_pcr_h - pcr_h) * 300 + (next_pcr_l - pcr_l)) /
1311                         (i + 1);
1312                     break;
1313                 }
1314             }
1315             url_fseek(&s->pb, pos, SEEK_SET);
1316             /* no next PCR found: we use previous increment */
1317             ts->cur_pcr = pcr_h * 300 + pcr_l;
1318         }
1319         pkt->pts = ts->cur_pcr;
1320         pkt->duration = ts->pcr_incr;
1321         ts->cur_pcr += ts->pcr_incr;
1322     }
1323     pkt->stream_index = 0;
1324     return 0;
1325 }
1326
1327 static int mpegts_read_packet(AVFormatContext *s,
1328                               AVPacket *pkt)
1329 {
1330     MpegTSContext *ts = s->priv_data;
1331
1332     ts->pkt = pkt;
1333     return handle_packets(ts, 0);
1334 }
1335
1336 static int mpegts_read_close(AVFormatContext *s)
1337 {
1338     MpegTSContext *ts = s->priv_data;
1339     int i;
1340     for(i=0;i<NB_PID_MAX;i++)
1341         if (ts->pids[i]) mpegts_close_filter(ts, ts->pids[i]);
1342
1343     return 0;
1344 }
1345
1346 static int64_t mpegts_get_pcr(AVFormatContext *s, int stream_index,
1347                               int64_t *ppos, int64_t pos_limit)
1348 {
1349     MpegTSContext *ts = s->priv_data;
1350     int64_t pos, timestamp;
1351     uint8_t buf[TS_PACKET_SIZE];
1352     int pcr_l, pcr_pid = ((PESContext*)s->streams[stream_index]->priv_data)->pcr_pid;
1353     const int find_next= 1;
1354     pos = ((*ppos  + ts->raw_packet_size - 1) / ts->raw_packet_size) * ts->raw_packet_size;
1355     if (find_next) {
1356         for(;;) {
1357             url_fseek(&s->pb, pos, SEEK_SET);
1358             if (get_buffer(&s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
1359                 return AV_NOPTS_VALUE;
1360             if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) &&
1361                 parse_pcr(&timestamp, &pcr_l, buf) == 0) {
1362                 break;
1363             }
1364             pos += ts->raw_packet_size;
1365         }
1366     } else {
1367         for(;;) {
1368             pos -= ts->raw_packet_size;
1369             if (pos < 0)
1370                 return AV_NOPTS_VALUE;
1371             url_fseek(&s->pb, pos, SEEK_SET);
1372             if (get_buffer(&s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
1373                 return AV_NOPTS_VALUE;
1374             if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) &&
1375                 parse_pcr(&timestamp, &pcr_l, buf) == 0) {
1376                 break;
1377             }
1378         }
1379     }
1380     *ppos = pos;
1381
1382     return timestamp;
1383 }
1384
1385 static int read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags){
1386     MpegTSContext *ts = s->priv_data;
1387     uint8_t buf[TS_PACKET_SIZE];
1388     int64_t pos;
1389
1390     if(av_seek_frame_binary(s, stream_index, target_ts, flags) < 0)
1391         return -1;
1392
1393     pos= url_ftell(&s->pb);
1394
1395     for(;;) {
1396         url_fseek(&s->pb, pos, SEEK_SET);
1397         if (get_buffer(&s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
1398             return -1;
1399 //        pid = AV_RB16(buf + 1) & 0x1fff;
1400         if(buf[1] & 0x40) break;
1401         pos += ts->raw_packet_size;
1402     }
1403     url_fseek(&s->pb, pos, SEEK_SET);
1404
1405     return 0;
1406 }
1407
1408 /**************************************************************/
1409 /* parsing functions - called from other demuxers such as RTP */
1410
1411 MpegTSContext *mpegts_parse_open(AVFormatContext *s)
1412 {
1413     MpegTSContext *ts;
1414
1415     ts = av_mallocz(sizeof(MpegTSContext));
1416     if (!ts)
1417         return NULL;
1418     /* no stream case, currently used by RTP */
1419     ts->raw_packet_size = TS_PACKET_SIZE;
1420     ts->stream = s;
1421     ts->auto_guess = 1;
1422     return ts;
1423 }
1424
1425 /* return the consumed length if a packet was output, or -1 if no
1426    packet is output */
1427 int mpegts_parse_packet(MpegTSContext *ts, AVPacket *pkt,
1428                         const uint8_t *buf, int len)
1429 {
1430     int len1;
1431
1432     len1 = len;
1433     ts->pkt = pkt;
1434     ts->stop_parse = 0;
1435     for(;;) {
1436         if (ts->stop_parse>0)
1437             break;
1438         if (len < TS_PACKET_SIZE)
1439             return -1;
1440         if (buf[0] != 0x47) {
1441             buf++;
1442             len--;
1443         } else {
1444             handle_packet(ts, buf);
1445             buf += TS_PACKET_SIZE;
1446             len -= TS_PACKET_SIZE;
1447         }
1448     }
1449     return len1 - len;
1450 }
1451
1452 void mpegts_parse_close(MpegTSContext *ts)
1453 {
1454     int i;
1455
1456     for(i=0;i<NB_PID_MAX;i++)
1457         av_free(ts->pids[i]);
1458     av_free(ts);
1459 }
1460
1461 AVInputFormat mpegts_demuxer = {
1462     "mpegts",
1463     "MPEG2 transport stream format",
1464     sizeof(MpegTSContext),
1465     mpegts_probe,
1466     mpegts_read_header,
1467     mpegts_read_packet,
1468     mpegts_read_close,
1469     read_seek,
1470     mpegts_get_pcr,
1471     .flags = AVFMT_SHOW_IDS,
1472 };
1473
1474 AVInputFormat mpegtsraw_demuxer = {
1475     "mpegtsraw",
1476     "MPEG2 raw transport stream format",
1477     sizeof(MpegTSContext),
1478     mpegts_probe,
1479     mpegts_read_header,
1480     mpegts_raw_read_packet,
1481     mpegts_read_close,
1482     read_seek,
1483     mpegts_get_pcr,
1484     .flags = AVFMT_SHOW_IDS,
1485 };