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 #define REGISTRATION_DESCRIPTOR 5
35
36 typedef struct PESContext PESContext;
37
38 static PESContext* add_pes_stream(MpegTSContext *ts, int pid, int pcr_pid, int stream_type);
39 static AVStream* new_pes_av_stream(PESContext *pes, uint32_t code);
40 extern void av_set_program_name(AVProgram *program, char *provider_name, char *name);
41 extern void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
42
43 enum MpegTSFilterType {
44 MPEGTS_PES,
45 MPEGTS_SECTION,
46 };
47
48 typedef struct MpegTSFilter MpegTSFilter;
49
50 typedef void PESCallback(MpegTSFilter *f, const uint8_t *buf, int len, int is_start);
51
52 typedef struct MpegTSPESFilter {
53 PESCallback *pes_cb;
54 void *opaque;
55 } MpegTSPESFilter;
56
57 typedef void SectionCallback(MpegTSFilter *f, const uint8_t *buf, int len);
58
59 typedef void SetServiceCallback(void *opaque, int ret);
60
61 typedef struct MpegTSSectionFilter {
62 int section_index;
63 int section_h_size;
64 uint8_t *section_buf;
65 int check_crc:1;
66 int end_of_section_reached:1;
67 SectionCallback *section_cb;
68 void *opaque;
69 } MpegTSSectionFilter;
70
71 struct MpegTSFilter {
72 int pid;
73 int last_cc; /* last cc code (-1 if first packet) */
74 enum MpegTSFilterType type;
75 union {
76 MpegTSPESFilter pes_filter;
77 MpegTSSectionFilter section_filter;
78 } u;
79 };
80
81 #define MAX_PIDS_PER_PROGRAM 64
82 typedef struct {
83 unsigned int id; //program id/service id
84 unsigned int nb_pids;
85 unsigned int pids[MAX_PIDS_PER_PROGRAM];
86 } Program_t;
87
88 struct MpegTSContext {
89 /* user data */
90 AVFormatContext *stream;
91 /** raw packet size, including FEC if present */
92 int raw_packet_size;
93
94 int pos47;
95
96 /** if true, all pids are analyzed to find streams */
97 int auto_guess;
98
99 /** compute exact PCR for each transport stream packet */
100 int mpeg2ts_compute_pcr;
101
102 int64_t cur_pcr; /**< used to estimate the exact PCR */
103 int pcr_incr; /**< used to estimate the exact PCR */
104
105 /* data needed to handle file based ts */
106 /** stop parsing loop */
107 int stop_parse;
108 /** packet containing Audio/Video data */
109 AVPacket *pkt;
110
111 /******************************************/
112 /* private mpegts data */
113 /* scan context */
114 /** structure to keep track of Program->pids mapping */
115 unsigned int nb_prg;
116 Program_t *prg;
117
118
119 /** filters for various streams specified by PMT + for the PAT and PMT */
120 MpegTSFilter *pids[NB_PID_MAX];
121 };
122
123 /* TS stream handling */
124
125 enum MpegTSState {
126 MPEGTS_HEADER = 0,
127 MPEGTS_PESHEADER_FILL,
128 MPEGTS_PAYLOAD,
129 MPEGTS_SKIP,
130 };
131
132 /* enough for PES header + length */
133 #define PES_START_SIZE 9
134 #define MAX_PES_HEADER_SIZE (9 + 255)
135
136 struct PESContext {
137 int pid;
138 int pcr_pid; /**< if -1 then all packets containing PCR are considered */
139 int stream_type;
140 MpegTSContext *ts;
141 AVFormatContext *stream;
142 AVStream *st;
143 enum MpegTSState state;
144 /* used to get the format */
145 int data_index;
146 int total_size;
147 int pes_header_size;
148 int64_t pts, dts;
149 uint8_t header[MAX_PES_HEADER_SIZE];
150 };
151
152 extern AVInputFormat mpegts_demuxer;
153
clear_program(MpegTSContext * ts,unsigned int programid)154 static void clear_program(MpegTSContext *ts, unsigned int programid)
155 {
156 int i;
157
158 for(i=0; i<ts->nb_prg; i++)
159 if(ts->prg[i].id == programid)
160 ts->prg[i].nb_pids = 0;
161 }
162
clear_programs(MpegTSContext * ts)163 static void clear_programs(MpegTSContext *ts)
164 {
165 av_freep(&ts->prg);
166 ts->nb_prg=0;
167 }
168
add_pat_entry(MpegTSContext * ts,unsigned int programid)169 static void add_pat_entry(MpegTSContext *ts, unsigned int programid)
170 {
171 Program_t *p;
172 void *tmp = av_realloc(ts->prg, (ts->nb_prg+1)*sizeof(Program_t));
173 if(!tmp)
174 return;
175 ts->prg = tmp;
176 p = &ts->prg[ts->nb_prg];
177 p->id = programid;
178 p->nb_pids = 0;
179 ts->nb_prg++;
180 }
181
add_pid_to_pmt(MpegTSContext * ts,unsigned int programid,unsigned int pid)182 static void add_pid_to_pmt(MpegTSContext *ts, unsigned int programid, unsigned int pid)
183 {
184 int i;
185 Program_t *p = NULL;
186 for(i=0; i<ts->nb_prg; i++) {
187 if(ts->prg[i].id == programid) {
188 p = &ts->prg[i];
189 break;
190 }
191 }
192 if(!p)
193 return;
194
195 if(p->nb_pids >= MAX_PIDS_PER_PROGRAM)
196 return;
197 p->pids[p->nb_pids++] = pid;
198 }
199
200 /**
201 * \brief discard_pid() decides if the pid is to be discarded according
202 * to caller's programs selection
203 * \param ts : - TS context
204 * \param pid : - pid
205 * \return 1 if the pid is only comprised in programs that have .discard=AVDISCARD_ALL
206 * 0 otherwise
207 */
discard_pid(MpegTSContext * ts,unsigned int pid)208 static int discard_pid(MpegTSContext *ts, unsigned int pid)
209 {
210 int i, j, k;
211 int used = 0, discarded = 0;
212 Program_t *p;
213 for(i=0; i<ts->nb_prg; i++) {
214 p = &ts->prg[i];
215 for(j=0; j<p->nb_pids; j++) {
216 if(p->pids[j] != pid)
217 continue;
218 //is program with id p->id set to be discarded?
219 for(k=0; k<ts->stream->nb_programs; k++) {
220 if(ts->stream->programs[k]->id == p->id) {
221 if(ts->stream->programs[k]->discard == AVDISCARD_ALL)
222 discarded++;
223 else
224 used++;
225 }
226 }
227 }
228 }
229
230 return (!used && discarded);
231 }
232
233 /**
234 * Assembles PES packets out of TS packets, and then calls the "section_cb"
235 * function when they are complete.
236 */
write_section_data(AVFormatContext * s,MpegTSFilter * tss1,const uint8_t * buf,int buf_size,int is_start)237 static void write_section_data(AVFormatContext *s, MpegTSFilter *tss1,
238 const uint8_t *buf, int buf_size, int is_start)
239 {
240 MpegTSSectionFilter *tss = &tss1->u.section_filter;
241 int len;
242
243 if (is_start) {
244 memcpy(tss->section_buf, buf, buf_size);
245 tss->section_index = buf_size;
246 tss->section_h_size = -1;
247 tss->end_of_section_reached = 0;
248 } else {
249 if (tss->end_of_section_reached)
250 return;
251 len = 4096 - tss->section_index;
252 if (buf_size < len)
253 len = buf_size;
254 memcpy(tss->section_buf + tss->section_index, buf, len);
255 tss->section_index += len;
256 }
257
258 /* compute section length if possible */
259 if (tss->section_h_size == -1 && tss->section_index >= 3) {
260 len = (AV_RB16(tss->section_buf + 1) & 0xfff) + 3;
261 if (len > 4096)
262 return;
263 tss->section_h_size = len;
264 }
265
266 if (tss->section_h_size != -1 && tss->section_index >= tss->section_h_size) {
267 tss->end_of_section_reached = 1;
268 if (!tss->check_crc ||
269 av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1,
270 tss->section_buf, tss->section_h_size) == 0)
271 tss->section_cb(tss1, tss->section_buf, tss->section_h_size);
272 }
273 }
274
mpegts_open_section_filter(MpegTSContext * ts,unsigned int pid,SectionCallback * section_cb,void * opaque,int check_crc)275 static MpegTSFilter *mpegts_open_section_filter(MpegTSContext *ts, unsigned int pid,
276 SectionCallback *section_cb, void *opaque,
277 int check_crc)
278
279 {
280 MpegTSFilter *filter;
281 MpegTSSectionFilter *sec;
282
283 #ifdef DEBUG_SI
284 av_log(ts->stream, AV_LOG_DEBUG, "Filter: pid=0x%x\n", pid);
285 #endif
286 if (pid >= NB_PID_MAX || ts->pids[pid])
287 return NULL;
288 filter = av_mallocz(sizeof(MpegTSFilter));
289 if (!filter)
290 return NULL;
291 ts->pids[pid] = filter;
292 filter->type = MPEGTS_SECTION;
293 filter->pid = pid;
294 filter->last_cc = -1;
295 sec = &filter->u.section_filter;
296 sec->section_cb = section_cb;
297 sec->opaque = opaque;
298 sec->section_buf = av_malloc(MAX_SECTION_SIZE);
299 sec->check_crc = check_crc;
300 if (!sec->section_buf) {
301 av_free(filter);
302 return NULL;
303 }
304 return filter;
305 }
306
mpegts_open_pes_filter(MpegTSContext * ts,unsigned int pid,PESCallback * pes_cb,void * opaque)307 static MpegTSFilter *mpegts_open_pes_filter(MpegTSContext *ts, unsigned int pid,
308 PESCallback *pes_cb,
309 void *opaque)
310 {
311 MpegTSFilter *filter;
312 MpegTSPESFilter *pes;
313
314 if (pid >= NB_PID_MAX || ts->pids[pid])
315 return NULL;
316 filter = av_mallocz(sizeof(MpegTSFilter));
317 if (!filter)
318 return NULL;
319 ts->pids[pid] = filter;
320 filter->type = MPEGTS_PES;
321 filter->pid = pid;
322 filter->last_cc = -1;
323 pes = &filter->u.pes_filter;
324 pes->pes_cb = pes_cb;
325 pes->opaque = opaque;
326 return filter;
327 }
328
mpegts_close_filter(MpegTSContext * ts,MpegTSFilter * filter)329 static void mpegts_close_filter(MpegTSContext *ts, MpegTSFilter *filter)
330 {
331 int pid;
332
333 pid = filter->pid;
334 if (filter->type == MPEGTS_SECTION)
335 av_freep(&filter->u.section_filter.section_buf);
336 else if (filter->type == MPEGTS_PES)
337 av_freep(&filter->u.pes_filter.opaque);
338
339 av_free(filter);
340 ts->pids[pid] = NULL;
341 }
342
analyze(const uint8_t * buf,int size,int packet_size,int * index)343 static int analyze(const uint8_t *buf, int size, int packet_size, int *index){
344 int stat[packet_size];
345 int i;
346 int x=0;
347 int best_score=0;
348
349 memset(stat, 0, packet_size*sizeof(int));
350
351 for(x=i=0; i<size; i++){
352 if(buf[i] == 0x47){
353 stat[x]++;
354 if(stat[x] > best_score){
355 best_score= stat[x];
356 if(index) *index= x;
357 }
358 }
359
360 x++;
361 if(x == packet_size) x= 0;
362 }
363
364 return best_score;
365 }
366
367 /* autodetect fec presence. Must have at least 1024 bytes */
get_packet_size(const uint8_t * buf,int size)368 static int get_packet_size(const uint8_t *buf, int size)
369 {
370 int score, fec_score, dvhs_score;
371
372 if (size < (TS_FEC_PACKET_SIZE * 5 + 1))
373 return -1;
374
375 score = analyze(buf, size, TS_PACKET_SIZE, NULL);
376 dvhs_score = analyze(buf, size, TS_DVHS_PACKET_SIZE, NULL);
377 fec_score= analyze(buf, size, TS_FEC_PACKET_SIZE, NULL);
378 // av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score);
379
380 if (score > fec_score && score > dvhs_score) return TS_PACKET_SIZE;
381 else if(dvhs_score > score && dvhs_score > fec_score) return TS_DVHS_PACKET_SIZE;
382 else if(score < fec_score && dvhs_score < fec_score) return TS_FEC_PACKET_SIZE;
383 else return -1;
384 }
385
386 typedef struct SectionHeader {
387 uint8_t tid;
388 uint16_t id;
389 uint8_t version;
390 uint8_t sec_num;
391 uint8_t last_sec_num;
392 } SectionHeader;
393
get8(const uint8_t ** pp,const uint8_t * p_end)394 static inline int get8(const uint8_t **pp, const uint8_t *p_end)
395 {
396 const uint8_t *p;
397 int c;
398
399 p = *pp;
400 if (p >= p_end)
401 return -1;
402 c = *p++;
403 *pp = p;
404 return c;
405 }
406
get16(const uint8_t ** pp,const uint8_t * p_end)407 static inline int get16(const uint8_t **pp, const uint8_t *p_end)
408 {
409 const uint8_t *p;
410 int c;
411
412 p = *pp;
413 if ((p + 1) >= p_end)
414 return -1;
415 c = AV_RB16(p);
416 p += 2;
417 *pp = p;
418 return c;
419 }
420
421 /* read and allocate a DVB string preceeded by its length */
getstr8(const uint8_t ** pp,const uint8_t * p_end)422 static char *getstr8(const uint8_t **pp, const uint8_t *p_end)
423 {
424 int len;
425 const uint8_t *p;
426 char *str;
427
428 p = *pp;
429 len = get8(&p, p_end);
430 if (len < 0)
431 return NULL;
432 if ((p + len) > p_end)
433 return NULL;
434 str = av_malloc(len + 1);
435 if (!str)
436 return NULL;
437 memcpy(str, p, len);
438 str[len] = '\0';
439 p += len;
440 *pp = p;
441 return str;
442 }
443
parse_section_header(SectionHeader * h,const uint8_t ** pp,const uint8_t * p_end)444 static int parse_section_header(SectionHeader *h,
445 const uint8_t **pp, const uint8_t *p_end)
446 {
447 int val;
448
449 val = get8(pp, p_end);
450 if (val < 0)
451 return -1;
452 h->tid = val;
453 *pp += 2;
454 val = get16(pp, p_end);
455 if (val < 0)
456 return -1;
457 h->id = val;
458 val = get8(pp, p_end);
459 if (val < 0)
460 return -1;
461 h->version = (val >> 1) & 0x1f;
462 val = get8(pp, p_end);
463 if (val < 0)
464 return -1;
465 h->sec_num = val;
466 val = get8(pp, p_end);
467 if (val < 0)
468 return -1;
469 h->last_sec_num = val;
470 return 0;
471 }
472
473
pmt_cb(MpegTSFilter * filter,const uint8_t * section,int section_len)474 static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
475 {
476 MpegTSContext *ts = filter->u.section_filter.opaque;
477 SectionHeader h1, *h = &h1;
478 PESContext *pes;
479 AVStream *st;
480 const uint8_t *p, *p_end, *desc_list_end, *desc_end;
481 int program_info_length, pcr_pid, pid, stream_type;
482 int desc_list_len, desc_len, desc_tag;
483 int comp_page = 0, anc_page = 0; /* initialize to kill warnings */
484 char language[4] = {0}; /* initialize to kill warnings */
485 int has_hdmv_descr = 0;
486
487 #ifdef DEBUG_SI
488 av_log(ts->stream, AV_LOG_DEBUG, "PMT: len %i\n", section_len);
489 av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len);
490 #endif
491 p_end = section + section_len - 4;
492 p = section;
493 if (parse_section_header(h, &p, p_end) < 0)
494 return;
495 #ifdef DEBUG_SI
496 av_log(ts->stream, AV_LOG_DEBUG, "sid=0x%x sec_num=%d/%d\n",
497 h->id, h->sec_num, h->last_sec_num);
498 #endif
499 if (h->tid != PMT_TID)
500 return;
501
502 clear_program(ts, h->id);
503 pcr_pid = get16(&p, p_end) & 0x1fff;
504 if (pcr_pid < 0)
505 return;
506 add_pid_to_pmt(ts, h->id, pcr_pid);
507 #ifdef DEBUG_SI
508 av_log(ts->stream, AV_LOG_DEBUG, "pcr_pid=0x%x\n", pcr_pid);
509 #endif
510 program_info_length = get16(&p, p_end) & 0xfff;
511 if (program_info_length < 0)
512 return;
513 while(program_info_length >= 2) {
514 uint8_t tag, len;
515 tag = get8(&p, p_end);
516 len = get8(&p, p_end);
517 if(len > program_info_length - 2)
518 //something else is broken, exit the program_descriptors_loop
519 break;
520 program_info_length -= len + 2;
521 if(tag == REGISTRATION_DESCRIPTOR && len >= 4) {
522 uint8_t bytes[4];
523 bytes[0] = get8(&p, p_end);
524 bytes[1] = get8(&p, p_end);
525 bytes[2] = get8(&p, p_end);
526 bytes[3] = get8(&p, p_end);
527 len -= 4;
528 if(bytes[0] == 'H' && bytes[1] == 'D' &&
529 bytes[2] == 'M' && bytes[3] == 'V')
530 has_hdmv_descr = 1;
531 }
532 p += len;
533 }
534 p += program_info_length;
535 if (p >= p_end)
536 return;
537 for(;;) {
538 language[0] = 0;
539 st = 0;
540 stream_type = get8(&p, p_end);
541 if (stream_type < 0)
542 break;
543 pid = get16(&p, p_end) & 0x1fff;
544 if (pid < 0)
545 break;
546 desc_list_len = get16(&p, p_end) & 0xfff;
547 if (desc_list_len < 0)
548 break;
549 desc_list_end = p + desc_list_len;
550 if (desc_list_end > p_end)
551 break;
552 for(;;) {
553 desc_tag = get8(&p, desc_list_end);
554 if (desc_tag < 0)
555 break;
556 if (stream_type == STREAM_TYPE_PRIVATE_DATA) {
557 if((desc_tag == 0x6A) || (desc_tag == 0x7A)) {
558 /*assume DVB AC-3 Audio*/
559 stream_type = STREAM_TYPE_AUDIO_AC3;
560 } else if(desc_tag == 0x7B) {
561 /* DVB DTS audio */
562 stream_type = STREAM_TYPE_AUDIO_DTS;
563 }
564 }
565 desc_len = get8(&p, desc_list_end);
566 desc_end = p + desc_len;
567 if (desc_end > desc_list_end)
568 break;
569 #ifdef DEBUG_SI
570 av_log(ts->stream, AV_LOG_DEBUG, "tag: 0x%02x len=%d\n",
571 desc_tag, desc_len);
572 #endif
573 switch(desc_tag) {
574 case DVB_SUBT_DESCID:
575 if (stream_type == STREAM_TYPE_PRIVATE_DATA)
576 stream_type = STREAM_TYPE_SUBTITLE_DVB;
577
578 language[0] = get8(&p, desc_end);
579 language[1] = get8(&p, desc_end);
580 language[2] = get8(&p, desc_end);
581 language[3] = 0;
582 get8(&p, desc_end);
583 comp_page = get16(&p, desc_end);
584 anc_page = get16(&p, desc_end);
585
586 break;
587 case 0x0a: /* ISO 639 language descriptor */
588 language[0] = get8(&p, desc_end);
589 language[1] = get8(&p, desc_end);
590 language[2] = get8(&p, desc_end);
591 language[3] = 0;
592 break;
593 default:
594 break;
595 }
596 p = desc_end;
597 }
598 p = desc_list_end;
599
600 #ifdef DEBUG_SI
601 av_log(ts->stream, AV_LOG_DEBUG, "stream_type=%d pid=0x%x\n",
602 stream_type, pid);
603 #endif
604
605 /* now create ffmpeg stream */
606 switch(stream_type) {
607 case STREAM_TYPE_AUDIO_MPEG1:
608 case STREAM_TYPE_AUDIO_MPEG2:
609 case STREAM_TYPE_VIDEO_MPEG1:
610 case STREAM_TYPE_VIDEO_MPEG2:
611 case STREAM_TYPE_VIDEO_MPEG4:
612 case STREAM_TYPE_VIDEO_H264:
613 case STREAM_TYPE_VIDEO_VC1:
614 case STREAM_TYPE_AUDIO_AAC:
615 case STREAM_TYPE_AUDIO_AC3:
616 case STREAM_TYPE_AUDIO_DTS:
617 case STREAM_TYPE_AUDIO_HDMV_DTS:
618 case STREAM_TYPE_SUBTITLE_DVB:
619 if(stream_type == STREAM_TYPE_AUDIO_HDMV_DTS && !has_hdmv_descr)
620 break;
621 if(ts->pids[pid] && ts->pids[pid]->type == MPEGTS_PES){
622 pes= ts->pids[pid]->u.pes_filter.opaque;
623 st= pes->st;
624 }else{
625 if (ts->pids[pid]) mpegts_close_filter(ts, ts->pids[pid]); //wrongly added sdt filter probably
626 pes = add_pes_stream(ts, pid, pcr_pid, stream_type);
627 if (pes)
628 st = new_pes_av_stream(pes, 0);
629 }
630 add_pid_to_pmt(ts, h->id, pid);
631 if(st)
632 av_program_add_stream_index(ts->stream, h->id, st->index);
633 break;
634 default:
635 /* we ignore the other streams */
636 break;
637 }
638
639 if (st) {
640 if (language[0] != 0) {
641 memcpy(st->language, language, 4);
642 }
643
644 if (stream_type == STREAM_TYPE_SUBTITLE_DVB) {
645 st->codec->sub_id = (anc_page << 16) | comp_page;
646 }
647 }
648 }
649 /* all parameters are there */
650 ts->stop_parse++;
651 mpegts_close_filter(ts, filter);
652 }
653
pat_cb(MpegTSFilter * filter,const uint8_t * section,int section_len)654 static void pat_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
655 {
656 MpegTSContext *ts = filter->u.section_filter.opaque;
657 SectionHeader h1, *h = &h1;
658 const uint8_t *p, *p_end;
659 int sid, pmt_pid;
660
661 #ifdef DEBUG_SI
662 av_log(ts->stream, AV_LOG_DEBUG, "PAT:\n");
663 av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len);
664 #endif
665 p_end = section + section_len - 4;
666 p = section;
667 if (parse_section_header(h, &p, p_end) < 0)
668 return;
669 if (h->tid != PAT_TID)
670 return;
671
672 clear_programs(ts);
673 for(;;) {
674 sid = get16(&p, p_end);
675 if (sid < 0)
676 break;
677 pmt_pid = get16(&p, p_end) & 0x1fff;
678 if (pmt_pid < 0)
679 break;
680 #ifdef DEBUG_SI
681 av_log(ts->stream, AV_LOG_DEBUG, "sid=0x%x pid=0x%x\n", sid, pmt_pid);
682 #endif
683 if (sid == 0x0000) {
684 /* NIT info */
685 } else {
686 av_new_program(ts->stream, sid);
687 ts->stop_parse--;
688 mpegts_open_section_filter(ts, pmt_pid, pmt_cb, ts, 1);
689 add_pat_entry(ts, sid);
690 add_pid_to_pmt(ts, sid, 0); //add pat pid to program
691 add_pid_to_pmt(ts, sid, pmt_pid);
692 }
693 }
694 /* not found */
695 ts->stop_parse++;
696
697 mpegts_close_filter(ts, filter);
698 }
699
mpegts_set_service(MpegTSContext * ts)700 static void mpegts_set_service(MpegTSContext *ts)
701 {
702 mpegts_open_section_filter(ts, PAT_PID,
703 pat_cb, ts, 1);
704 }
705
sdt_cb(MpegTSFilter * filter,const uint8_t * section,int section_len)706 static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len)
707 {
708 MpegTSContext *ts = filter->u.section_filter.opaque;
709 SectionHeader h1, *h = &h1;
710 const uint8_t *p, *p_end, *desc_list_end, *desc_end;
711 int onid, val, sid, desc_list_len, desc_tag, desc_len, service_type;
712 char *name, *provider_name;
713
714 #ifdef DEBUG_SI
715 av_log(ts->stream, AV_LOG_DEBUG, "SDT:\n");
716 av_hex_dump_log(ts->stream, AV_LOG_DEBUG, (uint8_t *)section, section_len);
717 #endif
718
719 p_end = section + section_len - 4;
720 p = section;
721 if (parse_section_header(h, &p, p_end) < 0)
722 return;
723 if (h->tid != SDT_TID)
724 return;
725 onid = get16(&p, p_end);
726 if (onid < 0)
727 return;
728 val = get8(&p, p_end);
729 if (val < 0)
730 return;
731 for(;;) {
732 sid = get16(&p, p_end);
733 if (sid < 0)
734 break;
735 val = get8(&p, p_end);
736 if (val < 0)
737 break;
738 desc_list_len = get16(&p, p_end) & 0xfff;
739 if (desc_list_len < 0)
740 break;
741 desc_list_end = p + desc_list_len;
742 if (desc_list_end > p_end)
743 break;
744 for(;;) {
745 desc_tag = get8(&p, desc_list_end);
746 if (desc_tag < 0)
747 break;
748 desc_len = get8(&p, desc_list_end);
749 desc_end = p + desc_len;
750 if (desc_end > desc_list_end)
751 break;
752 #ifdef DEBUG_SI
753 av_log(ts->stream, AV_LOG_DEBUG, "tag: 0x%02x len=%d\n",
754 desc_tag, desc_len);
755 #endif
756 switch(desc_tag) {
757 case 0x48:
758 service_type = get8(&p, p_end);
759 if (service_type < 0)
760 break;
761 provider_name = getstr8(&p, p_end);
762 if (!provider_name)
763 break;
764 name = getstr8(&p, p_end);
765 if (name) {
766 AVProgram *program = av_new_program(ts->stream, sid);
767 if(program)
768 av_set_program_name(program, provider_name, name);
769 }
770 av_free(name);
771 av_free(provider_name);
772 break;
773 default:
774 break;
775 }
776 p = desc_end;
777 }
778 p = desc_list_end;
779 }
780 }
781
782 /* scan services in a transport stream by looking at the SDT */
mpegts_scan_sdt(MpegTSContext * ts)783 static void mpegts_scan_sdt(MpegTSContext *ts)
784 {
785 mpegts_open_section_filter(ts, SDT_PID,
786 sdt_cb, ts, 1);
787 }
788
get_pts(const uint8_t * p)789 static int64_t get_pts(const uint8_t *p)
790 {
791 int64_t pts = (int64_t)((p[0] >> 1) & 0x07) << 30;
792 pts |= (AV_RB16(p + 1) >> 1) << 15;
793 pts |= AV_RB16(p + 3) >> 1;
794 return pts;
795 }
796
797 /* return non zero if a packet could be constructed */
mpegts_push_data(MpegTSFilter * filter,const uint8_t * buf,int buf_size,int is_start)798 static void mpegts_push_data(MpegTSFilter *filter,
799 const uint8_t *buf, int buf_size, int is_start)
800 {
801 PESContext *pes = filter->u.pes_filter.opaque;
802 MpegTSContext *ts = pes->ts;
803 const uint8_t *p;
804 int len, code;
805
806 if(!ts->pkt)
807 return;
808
809 if (is_start) {
810 pes->state = MPEGTS_HEADER;
811 pes->data_index = 0;
812 }
813 p = buf;
814 while (buf_size > 0) {
815 switch(pes->state) {
816 case MPEGTS_HEADER:
817 len = PES_START_SIZE - pes->data_index;
818 if (len > buf_size)
819 len = buf_size;
820 memcpy(pes->header + pes->data_index, p, len);
821 pes->data_index += len;
822 p += len;
823 buf_size -= len;
824 if (pes->data_index == PES_START_SIZE) {
825 /* we got all the PES or section header. We can now
826 decide */
827 #if 0
828 av_hex_dump_log(pes->stream, AV_LOG_DEBUG, pes->header, pes->data_index);
829 #endif
830 if (pes->header[0] == 0x00 && pes->header[1] == 0x00 &&
831 pes->header[2] == 0x01) {
832 /* it must be an mpeg2 PES stream */
833 code = pes->header[3] | 0x100;
834 if (!((code >= 0x1c0 && code <= 0x1df) ||
835 (code >= 0x1e0 && code <= 0x1ef) ||
836 (code == 0x1bd) || (code == 0x1fd)))
837 goto skip;
838 if (!pes->st) {
839 /* allocate stream */
840 new_pes_av_stream(pes, code);
841 }
842 pes->state = MPEGTS_PESHEADER_FILL;
843 pes->total_size = AV_RB16(pes->header + 4);
844 /* NOTE: a zero total size means the PES size is
845 unbounded */
846 if (pes->total_size)
847 pes->total_size += 6;
848 pes->pes_header_size = pes->header[8] + 9;
849 } else {
850 /* otherwise, it should be a table */
851 /* skip packet */
852 skip:
853 pes->state = MPEGTS_SKIP;
854 continue;
855 }
856 }
857 break;
858 /**********************************************/
859 /* PES packing parsing */
860 case MPEGTS_PESHEADER_FILL:
861 len = pes->pes_header_size - pes->data_index;
862 if (len > buf_size)
863 len = buf_size;
864 memcpy(pes->header + pes->data_index, p, len);
865 pes->data_index += len;
866 p += len;
867 buf_size -= len;
868 if (pes->data_index == pes->pes_header_size) {
869 const uint8_t *r;
870 unsigned int flags;
871
872 flags = pes->header[7];
873 r = pes->header + 9;
874 pes->pts = AV_NOPTS_VALUE;
875 pes->dts = AV_NOPTS_VALUE;
876 if ((flags & 0xc0) == 0x80) {
877 pes->pts = get_pts(r);
878 r += 5;
879 } else if ((flags & 0xc0) == 0xc0) {
880 pes->pts = get_pts(r);
881 r += 5;
882 pes->dts = get_pts(r);
883 r += 5;
884 }
885 /* we got the full header. We parse it and get the payload */
886 pes->state = MPEGTS_PAYLOAD;
887 }
888 break;
889 case MPEGTS_PAYLOAD:
890 if (pes->total_size) {
891 len = pes->total_size - pes->data_index;
892 if (len > buf_size)
893 len = buf_size;
894 } else {
895 len = buf_size;
896 }
897 if (len > 0) {
898 AVPacket *pkt = ts->pkt;
899 if (pes->st && av_new_packet(pkt, len) == 0) {
900 memcpy(pkt->data, p, len);
901 pkt->stream_index = pes->st->index;
902 pkt->pts = pes->pts;
903 pkt->dts = pes->dts;
904 /* reset pts values */
905 pes->pts = AV_NOPTS_VALUE;
906 pes->dts = AV_NOPTS_VALUE;
907 ts->stop_parse = 1;
908 return;
909 }
910 }
911 buf_size = 0;
912 break;
913 case MPEGTS_SKIP:
914 buf_size = 0;
915 break;
916 }
917 }
918 }
919
new_pes_av_stream(PESContext * pes,uint32_t code)920 static AVStream* new_pes_av_stream(PESContext *pes, uint32_t code)
921 {
922 AVStream *st;
923 int codec_type, codec_id;
924
925 switch(pes->stream_type){
926 case STREAM_TYPE_AUDIO_MPEG1:
927 case STREAM_TYPE_AUDIO_MPEG2:
928 codec_type = CODEC_TYPE_AUDIO;
929 codec_id = CODEC_ID_MP3;
930 break;
931 case STREAM_TYPE_VIDEO_MPEG1:
932 case STREAM_TYPE_VIDEO_MPEG2:
933 codec_type = CODEC_TYPE_VIDEO;
934 codec_id = CODEC_ID_MPEG2VIDEO;
935 break;
936 case STREAM_TYPE_VIDEO_MPEG4:
937 codec_type = CODEC_TYPE_VIDEO;
938 codec_id = CODEC_ID_MPEG4;
939 break;
940 case STREAM_TYPE_VIDEO_H264:
941 codec_type = CODEC_TYPE_VIDEO;
942 codec_id = CODEC_ID_H264;
943 break;
944 case STREAM_TYPE_VIDEO_VC1:
945 codec_type = CODEC_TYPE_VIDEO;
946 codec_id = CODEC_ID_VC1;
947 break;
948 case STREAM_TYPE_AUDIO_AAC:
949 codec_type = CODEC_TYPE_AUDIO;
950 codec_id = CODEC_ID_AAC;
951 break;
952 case STREAM_TYPE_AUDIO_AC3:
953 codec_type = CODEC_TYPE_AUDIO;
954 codec_id = CODEC_ID_AC3;
955 break;
956 case STREAM_TYPE_AUDIO_DTS:
957 case STREAM_TYPE_AUDIO_HDMV_DTS:
958 codec_type = CODEC_TYPE_AUDIO;
959 codec_id = CODEC_ID_DTS;
960 break;
961 case STREAM_TYPE_SUBTITLE_DVB:
962 codec_type = CODEC_TYPE_SUBTITLE;
963 codec_id = CODEC_ID_DVB_SUBTITLE;
964 break;
965 default:
966 if (code >= 0x1c0 && code <= 0x1df) {
967 codec_type = CODEC_TYPE_AUDIO;
968 codec_id = CODEC_ID_MP2;
969 } else if (code == 0x1bd) {
970 codec_type = CODEC_TYPE_AUDIO;
971 codec_id = CODEC_ID_AC3;
972 } else {
973 codec_type = CODEC_TYPE_VIDEO;
974 codec_id = CODEC_ID_MPEG1VIDEO;
975 }
976 break;
977 }
978 st = av_new_stream(pes->stream, pes->pid);
979 if (st) {
980 av_set_pts_info(st, 33, 1, 90000);
981 st->priv_data = pes;
982 st->codec->codec_type = codec_type;
983 st->codec->codec_id = codec_id;
984 st->need_parsing = AVSTREAM_PARSE_FULL;
985 pes->st = st;
986 }
987 return st;
988 }
989
990
add_pes_stream(MpegTSContext * ts,int pid,int pcr_pid,int stream_type)991 static PESContext *add_pes_stream(MpegTSContext *ts, int pid, int pcr_pid, int stream_type)
992 {
993 MpegTSFilter *tss;
994 PESContext *pes;
995
996 /* if no pid found, then add a pid context */
997 pes = av_mallocz(sizeof(PESContext));
998 if (!pes)
999 return 0;
1000 pes->ts = ts;
1001 pes->stream = ts->stream;
1002 pes->pid = pid;
1003 pes->pcr_pid = pcr_pid;
1004 pes->stream_type = stream_type;
1005 tss = mpegts_open_pes_filter(ts, pid, mpegts_push_data, pes);
1006 if (!tss) {
1007 av_free(pes);
1008 return 0;
1009 }
1010 return pes;
1011 }
1012
1013 /* handle one TS packet */
handle_packet(MpegTSContext * ts,const uint8_t * packet)1014 static void handle_packet(MpegTSContext *ts, const uint8_t *packet)
1015 {
1016 AVFormatContext *s = ts->stream;
1017 MpegTSFilter *tss;
1018 int len, pid, cc, cc_ok, afc, is_start;
1019 const uint8_t *p, *p_end;
1020
1021 pid = AV_RB16(packet + 1) & 0x1fff;
1022 if(pid && discard_pid(ts, pid))
1023 return;
1024 is_start = packet[1] & 0x40;
1025 tss = ts->pids[pid];
1026 if (ts->auto_guess && tss == NULL && is_start) {
1027 add_pes_stream(ts, pid, -1, 0);
1028 tss = ts->pids[pid];
1029 }
1030 if (!tss)
1031 return;
1032
1033 /* continuity check (currently not used) */
1034 cc = (packet[3] & 0xf);
1035 cc_ok = (tss->last_cc < 0) || ((((tss->last_cc + 1) & 0x0f) == cc));
1036 tss->last_cc = cc;
1037
1038 /* skip adaptation field */
1039 afc = (packet[3] >> 4) & 3;
1040 p = packet + 4;
1041 if (afc == 0) /* reserved value */
1042 return;
1043 if (afc == 2) /* adaptation field only */
1044 return;
1045 if (afc == 3) {
1046 /* skip adapation field */
1047 p += p[0] + 1;
1048 }
1049 /* if past the end of packet, ignore */
1050 p_end = packet + TS_PACKET_SIZE;
1051 if (p >= p_end)
1052 return;
1053
1054 ts->pos47= url_ftell(ts->stream->pb) % ts->raw_packet_size;
1055
1056 if (tss->type == MPEGTS_SECTION) {
1057 if (is_start) {
1058 /* pointer field present */
1059 len = *p++;
1060 if (p + len > p_end)
1061 return;
1062 if (len && cc_ok) {
1063 /* write remaining section bytes */
1064 write_section_data(s, tss,
1065 p, len, 0);
1066 /* check whether filter has been closed */
1067 if (!ts->pids[pid])
1068 return;
1069 }
1070 p += len;
1071 if (p < p_end) {
1072 write_section_data(s, tss,
1073 p, p_end - p, 1);
1074 }
1075 } else {
1076 if (cc_ok) {
1077 write_section_data(s, tss,
1078 p, p_end - p, 0);
1079 }
1080 }
1081 } else {
1082 tss->u.pes_filter.pes_cb(tss,
1083 p, p_end - p, is_start);
1084 }
1085 }
1086
1087 /* XXX: try to find a better synchro over several packets (use
1088 get_packet_size() ?) */
mpegts_resync(ByteIOContext * pb)1089 static int mpegts_resync(ByteIOContext *pb)
1090 {
1091 int c, i;
1092
1093 for(i = 0;i < MAX_RESYNC_SIZE; i++) {
1094 c = url_fgetc(pb);
1095 if (c < 0)
1096 return -1;
1097 if (c == 0x47) {
1098 url_fseek(pb, -1, SEEK_CUR);
1099 return 0;
1100 }
1101 }
1102 /* no sync found */
1103 return -1;
1104 }
1105
1106 /* return -1 if error or EOF. Return 0 if OK. */
read_packet(ByteIOContext * pb,uint8_t * buf,int raw_packet_size)1107 static int read_packet(ByteIOContext *pb, uint8_t *buf, int raw_packet_size)
1108 {
1109 int skip, len;
1110
1111 for(;;) {
1112 len = get_buffer(pb, buf, TS_PACKET_SIZE);
1113 if (len != TS_PACKET_SIZE)
1114 return AVERROR(EIO);
1115 /* check paquet sync byte */
1116 if (buf[0] != 0x47) {
1117 /* find a new packet start */
1118 url_fseek(pb, -TS_PACKET_SIZE, SEEK_CUR);
1119 if (mpegts_resync(pb) < 0)
1120 return AVERROR_INVALIDDATA;
1121 else
1122 continue;
1123 } else {
1124 skip = raw_packet_size - TS_PACKET_SIZE;
1125 if (skip > 0)
1126 url_fskip(pb, skip);
1127 break;
1128 }
1129 }
1130 return 0;
1131 }
1132
handle_packets(MpegTSContext * ts,int nb_packets)1133 static int handle_packets(MpegTSContext *ts, int nb_packets)
1134 {
1135 AVFormatContext *s = ts->stream;
1136 ByteIOContext *pb = s->pb;
1137 uint8_t packet[TS_PACKET_SIZE];
1138 int packet_num, ret;
1139
1140 ts->stop_parse = 0;
1141 packet_num = 0;
1142 for(;;) {
1143 if (ts->stop_parse>0)
1144 break;
1145 packet_num++;
1146 if (nb_packets != 0 && packet_num >= nb_packets)
1147 break;
1148 ret = read_packet(pb, packet, ts->raw_packet_size);
1149 if (ret != 0)
1150 return ret;
1151 handle_packet(ts, packet);
1152 }
1153 return 0;
1154 }
1155
mpegts_probe(AVProbeData * p)1156 static int mpegts_probe(AVProbeData *p)
1157 {
1158 #if 1
1159 const int size= p->buf_size;
1160 int score, fec_score, dvhs_score;
1161 #define CHECK_COUNT 10
1162
1163 if (size < (TS_FEC_PACKET_SIZE * CHECK_COUNT))
1164 return -1;
1165
1166 score = analyze(p->buf, TS_PACKET_SIZE *CHECK_COUNT, TS_PACKET_SIZE, NULL);
1167 dvhs_score = analyze(p->buf, TS_DVHS_PACKET_SIZE *CHECK_COUNT, TS_DVHS_PACKET_SIZE, NULL);
1168 fec_score= analyze(p->buf, TS_FEC_PACKET_SIZE*CHECK_COUNT, TS_FEC_PACKET_SIZE, NULL);
1169 // av_log(NULL, AV_LOG_DEBUG, "score: %d, dvhs_score: %d, fec_score: %d \n", score, dvhs_score, fec_score);
1170
1171 // we need a clear definition for the returned score otherwise things will become messy sooner or later
1172 if (score > fec_score && score > dvhs_score && score > 6) return AVPROBE_SCORE_MAX + score - CHECK_COUNT;
1173 else if(dvhs_score > score && dvhs_score > fec_score && dvhs_score > 6) return AVPROBE_SCORE_MAX + dvhs_score - CHECK_COUNT;
1174 else if( fec_score > 6) return AVPROBE_SCORE_MAX + fec_score - CHECK_COUNT;
1175 else return -1;
1176 #else
1177 /* only use the extension for safer guess */
1178 if (match_ext(p->filename, "ts"))
1179 return AVPROBE_SCORE_MAX;
1180 else
1181 return 0;
1182 #endif
1183 }
1184
1185 /* return the 90 kHz PCR and the extension for the 27 MHz PCR. return
1186 (-1) if not available */
parse_pcr(int64_t * ppcr_high,int * ppcr_low,const uint8_t * packet)1187 static int parse_pcr(int64_t *ppcr_high, int *ppcr_low,
1188 const uint8_t *packet)
1189 {
1190 int afc, len, flags;
1191 const uint8_t *p;
1192 unsigned int v;
1193
1194 afc = (packet[3] >> 4) & 3;
1195 if (afc <= 1)
1196 return -1;
1197 p = packet + 4;
1198 len = p[0];
1199 p++;
1200 if (len == 0)
1201 return -1;
1202 flags = *p++;
1203 len--;
1204 if (!(flags & 0x10))
1205 return -1;
1206 if (len < 6)
1207 return -1;
1208 v = AV_RB32(p);
1209 *ppcr_high = ((int64_t)v << 1) | (p[4] >> 7);
1210 *ppcr_low = ((p[4] & 1) << 8) | p[5];
1211 return 0;
1212 }
1213
mpegts_read_header(AVFormatContext * s,AVFormatParameters * ap)1214 static int mpegts_read_header(AVFormatContext *s,
1215 AVFormatParameters *ap)
1216 {
1217 MpegTSContext *ts = s->priv_data;
1218 ByteIOContext *pb = s->pb;
1219 uint8_t buf[1024];
1220 int len;
1221 int64_t pos;
1222
1223 if (ap) {
1224 ts->mpeg2ts_compute_pcr = ap->mpeg2ts_compute_pcr;
1225 if(ap->mpeg2ts_raw){
1226 av_log(s, AV_LOG_ERROR, "use mpegtsraw_demuxer!\n");
1227 return -1;
1228 }
1229 }
1230
1231 /* read the first 1024 bytes to get packet size */
1232 pos = url_ftell(pb);
1233 len = get_buffer(pb, buf, sizeof(buf));
1234 if (len != sizeof(buf))
1235 goto fail;
1236 ts->raw_packet_size = get_packet_size(buf, sizeof(buf));
1237 if (ts->raw_packet_size <= 0)
1238 goto fail;
1239 ts->stream = s;
1240 ts->auto_guess = 0;
1241
1242 if (s->iformat == &mpegts_demuxer) {
1243 /* normal demux */
1244
1245 /* first do a scaning to get all the services */
1246 url_fseek(pb, pos, SEEK_SET);
1247 mpegts_scan_sdt(ts);
1248
1249 mpegts_set_service(ts);
1250
1251 handle_packets(ts, s->probesize);
1252 /* if could not find service, enable auto_guess */
1253
1254 ts->auto_guess = 1;
1255
1256 #ifdef DEBUG_SI
1257 av_log(ts->stream, AV_LOG_DEBUG, "tuning done\n");
1258 #endif
1259 s->ctx_flags |= AVFMTCTX_NOHEADER;
1260 } else {
1261 AVStream *st;
1262 int pcr_pid, pid, nb_packets, nb_pcrs, ret, pcr_l;
1263 int64_t pcrs[2], pcr_h;
1264 int packet_count[2];
1265 uint8_t packet[TS_PACKET_SIZE];
1266
1267 /* only read packets */
1268
1269 st = av_new_stream(s, 0);
1270 if (!st)
1271 goto fail;
1272 av_set_pts_info(st, 60, 1, 27000000);
1273 st->codec->codec_type = CODEC_TYPE_DATA;
1274 st->codec->codec_id = CODEC_ID_MPEG2TS;
1275
1276 /* we iterate until we find two PCRs to estimate the bitrate */
1277 pcr_pid = -1;
1278 nb_pcrs = 0;
1279 nb_packets = 0;
1280 for(;;) {
1281 ret = read_packet(s->pb, packet, ts->raw_packet_size);
1282 if (ret < 0)
1283 return -1;
1284 pid = AV_RB16(packet + 1) & 0x1fff;
1285 if ((pcr_pid == -1 || pcr_pid == pid) &&
1286 parse_pcr(&pcr_h, &pcr_l, packet) == 0) {
1287 pcr_pid = pid;
1288 packet_count[nb_pcrs] = nb_packets;
1289 pcrs[nb_pcrs] = pcr_h * 300 + pcr_l;
1290 nb_pcrs++;
1291 if (nb_pcrs >= 2)
1292 break;
1293 }
1294 nb_packets++;
1295 }
1296
1297 /* NOTE1: the bitrate is computed without the FEC */
1298 /* NOTE2: it is only the bitrate of the start of the stream */
1299 ts->pcr_incr = (pcrs[1] - pcrs[0]) / (packet_count[1] - packet_count[0]);
1300 ts->cur_pcr = pcrs[0] - ts->pcr_incr * packet_count[0];
1301 s->bit_rate = (TS_PACKET_SIZE * 8) * 27e6 / ts->pcr_incr;
1302 st->codec->bit_rate = s->bit_rate;
1303 st->start_time = ts->cur_pcr;
1304 #if 0
1305 av_log(ts->stream, AV_LOG_DEBUG, "start=%0.3f pcr=%0.3f incr=%d\n",
1306 st->start_time / 1000000.0, pcrs[0] / 27e6, ts->pcr_incr);
1307 #endif
1308 }
1309
1310 url_fseek(pb, pos, SEEK_SET);
1311 return 0;
1312 fail:
1313 return -1;
1314 }
1315
1316 #define MAX_PACKET_READAHEAD ((128 * 1024) / 188)
1317
mpegts_raw_read_packet(AVFormatContext * s,AVPacket * pkt)1318 static int mpegts_raw_read_packet(AVFormatContext *s,
1319 AVPacket *pkt)
1320 {
1321 MpegTSContext *ts = s->priv_data;
1322 int ret, i;
1323 int64_t pcr_h, next_pcr_h, pos;
1324 int pcr_l, next_pcr_l;
1325 uint8_t pcr_buf[12];
1326
1327 if (av_new_packet(pkt, TS_PACKET_SIZE) < 0)
1328 return AVERROR(ENOMEM);
1329 pkt->pos= url_ftell(s->pb);
1330 ret = read_packet(s->pb, pkt->data, ts->raw_packet_size);
1331 if (ret < 0) {
1332 av_free_packet(pkt);
1333 return ret;
1334 }
1335 if (ts->mpeg2ts_compute_pcr) {
1336 /* compute exact PCR for each packet */
1337 if (parse_pcr(&pcr_h, &pcr_l, pkt->data) == 0) {
1338 /* we read the next PCR (XXX: optimize it by using a bigger buffer */
1339 pos = url_ftell(s->pb);
1340 for(i = 0; i < MAX_PACKET_READAHEAD; i++) {
1341 url_fseek(s->pb, pos + i * ts->raw_packet_size, SEEK_SET);
1342 get_buffer(s->pb, pcr_buf, 12);
1343 if (parse_pcr(&next_pcr_h, &next_pcr_l, pcr_buf) == 0) {
1344 /* XXX: not precise enough */
1345 ts->pcr_incr = ((next_pcr_h - pcr_h) * 300 + (next_pcr_l - pcr_l)) /
1346 (i + 1);
1347 break;
1348 }
1349 }
1350 url_fseek(s->pb, pos, SEEK_SET);
1351 /* no next PCR found: we use previous increment */
1352 ts->cur_pcr = pcr_h * 300 + pcr_l;
1353 }
1354 pkt->pts = ts->cur_pcr;
1355 pkt->duration = ts->pcr_incr;
1356 ts->cur_pcr += ts->pcr_incr;
1357 }
1358 pkt->stream_index = 0;
1359 return 0;
1360 }
1361
mpegts_read_packet(AVFormatContext * s,AVPacket * pkt)1362 static int mpegts_read_packet(AVFormatContext *s,
1363 AVPacket *pkt)
1364 {
1365 MpegTSContext *ts = s->priv_data;
1366
1367 ts->pkt = pkt;
1368 return handle_packets(ts, 0);
1369 }
1370
mpegts_read_close(AVFormatContext * s)1371 static int mpegts_read_close(AVFormatContext *s)
1372 {
1373 MpegTSContext *ts = s->priv_data;
1374 int i;
1375
1376 clear_programs(ts);
1377
1378 for(i=0;i<NB_PID_MAX;i++)
1379 if (ts->pids[i]) mpegts_close_filter(ts, ts->pids[i]);
1380
1381 return 0;
1382 }
1383
mpegts_get_pcr(AVFormatContext * s,int stream_index,int64_t * ppos,int64_t pos_limit)1384 static int64_t mpegts_get_pcr(AVFormatContext *s, int stream_index,
1385 int64_t *ppos, int64_t pos_limit)
1386 {
1387 MpegTSContext *ts = s->priv_data;
1388 int64_t pos, timestamp;
1389 uint8_t buf[TS_PACKET_SIZE];
1390 int pcr_l, pcr_pid = ((PESContext*)s->streams[stream_index]->priv_data)->pcr_pid;
1391 const int find_next= 1;
1392 pos = ((*ppos + ts->raw_packet_size - 1 - ts->pos47) / ts->raw_packet_size) * ts->raw_packet_size + ts->pos47;
1393 if (find_next) {
1394 for(;;) {
1395 url_fseek(s->pb, pos, SEEK_SET);
1396 if (get_buffer(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
1397 return AV_NOPTS_VALUE;
1398 if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) &&
1399 parse_pcr(×tamp, &pcr_l, buf) == 0) {
1400 break;
1401 }
1402 pos += ts->raw_packet_size;
1403 }
1404 } else {
1405 for(;;) {
1406 pos -= ts->raw_packet_size;
1407 if (pos < 0)
1408 return AV_NOPTS_VALUE;
1409 url_fseek(s->pb, pos, SEEK_SET);
1410 if (get_buffer(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
1411 return AV_NOPTS_VALUE;
1412 if ((pcr_pid < 0 || (AV_RB16(buf + 1) & 0x1fff) == pcr_pid) &&
1413 parse_pcr(×tamp, &pcr_l, buf) == 0) {
1414 break;
1415 }
1416 }
1417 }
1418 *ppos = pos;
1419
1420 return timestamp;
1421 }
1422
read_seek(AVFormatContext * s,int stream_index,int64_t target_ts,int flags)1423 static int read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags){
1424 MpegTSContext *ts = s->priv_data;
1425 uint8_t buf[TS_PACKET_SIZE];
1426 int64_t pos;
1427
1428 if(av_seek_frame_binary(s, stream_index, target_ts, flags) < 0)
1429 return -1;
1430
1431 pos= url_ftell(s->pb);
1432
1433 for(;;) {
1434 url_fseek(s->pb, pos, SEEK_SET);
1435 if (get_buffer(s->pb, buf, TS_PACKET_SIZE) != TS_PACKET_SIZE)
1436 return -1;
1437 // pid = AV_RB16(buf + 1) & 0x1fff;
1438 if(buf[1] & 0x40) break;
1439 pos += ts->raw_packet_size;
1440 }
1441 url_fseek(s->pb, pos, SEEK_SET);
1442
1443 return 0;
1444 }
1445
1446 /**************************************************************/
1447 /* parsing functions - called from other demuxers such as RTP */
1448
mpegts_parse_open(AVFormatContext * s)1449 MpegTSContext *mpegts_parse_open(AVFormatContext *s)
1450 {
1451 MpegTSContext *ts;
1452
1453 ts = av_mallocz(sizeof(MpegTSContext));
1454 if (!ts)
1455 return NULL;
1456 /* no stream case, currently used by RTP */
1457 ts->raw_packet_size = TS_PACKET_SIZE;
1458 ts->stream = s;
1459 ts->auto_guess = 1;
1460 return ts;
1461 }
1462
1463 /* return the consumed length if a packet was output, or -1 if no
1464 packet is output */
mpegts_parse_packet(MpegTSContext * ts,AVPacket * pkt,const uint8_t * buf,int len)1465 int mpegts_parse_packet(MpegTSContext *ts, AVPacket *pkt,
1466 const uint8_t *buf, int len)
1467 {
1468 int len1;
1469
1470 len1 = len;
1471 ts->pkt = pkt;
1472 ts->stop_parse = 0;
1473 for(;;) {
1474 if (ts->stop_parse>0)
1475 break;
1476 if (len < TS_PACKET_SIZE)
1477 return -1;
1478 if (buf[0] != 0x47) {
1479 buf++;
1480 len--;
1481 } else {
1482 handle_packet(ts, buf);
1483 buf += TS_PACKET_SIZE;
1484 len -= TS_PACKET_SIZE;
1485 }
1486 }
1487 return len1 - len;
1488 }
1489
mpegts_parse_close(MpegTSContext * ts)1490 void mpegts_parse_close(MpegTSContext *ts)
1491 {
1492 int i;
1493
1494 for(i=0;i<NB_PID_MAX;i++)
1495 av_free(ts->pids[i]);
1496 av_free(ts);
1497 }
1498
1499 AVInputFormat mpegts_demuxer = {
1500 "mpegts",
1501 "MPEG2 transport stream format",
1502 sizeof(MpegTSContext),
1503 mpegts_probe,
1504 mpegts_read_header,
1505 mpegts_read_packet,
1506 mpegts_read_close,
1507 read_seek,
1508 mpegts_get_pcr,
1509 .flags = AVFMT_SHOW_IDS,
1510 };
1511
1512 AVInputFormat mpegtsraw_demuxer = {
1513 "mpegtsraw",
1514 "MPEG2 raw transport stream format",
1515 sizeof(MpegTSContext),
1516 NULL,
1517 mpegts_read_header,
1518 mpegts_raw_read_packet,
1519 mpegts_read_close,
1520 read_seek,
1521 mpegts_get_pcr,
1522 .flags = AVFMT_SHOW_IDS,
1523 };
1524