2 * MPEG2 transport stream (aka DVB) muxer
3 * Copyright (c) 2003 Fabrice Bellard.
5 * This file is part of FFmpeg.
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.
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.
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
25 /* write DVB SI sections */
27 /*********************************************/
28 /* mpegts section writer */
30 typedef struct MpegTSSection {
33 void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
37 /* NOTE: 4 bytes must be left at the end for the crc32 */
38 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
41 unsigned char packet[TS_PACKET_SIZE];
42 const unsigned char *buf_ptr;
44 int first, b, len1, left;
46 crc = bswap_32(av_crc(av_crc04C11DB7, -1, buf, len - 4));
47 buf[len - 4] = (crc >> 24) & 0xff;
48 buf[len - 3] = (crc >> 16) & 0xff;
49 buf[len - 2] = (crc >> 8) & 0xff;
50 buf[len - 1] = (crc) & 0xff;
52 /* send each packet */
55 first = (buf == buf_ptr);
63 s->cc = (s->cc + 1) & 0xf;
66 *q++ = 0; /* 0 offset */
67 len1 = TS_PACKET_SIZE - (q - packet);
70 memcpy(q, buf_ptr, len1);
72 /* add known padding data */
73 left = TS_PACKET_SIZE - (q - packet);
75 memset(q, 0xff, left);
77 s->write_packet(s, packet);
84 static inline void put16(uint8_t **q_ptr, int val)
93 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
94 int version, int sec_num, int last_sec_num,
95 uint8_t *buf, int len)
97 uint8_t section[1024], *q;
100 tot_len = 3 + 5 + len + 4;
101 /* check if not too big */
107 put16(&q, 0xb000 | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
109 *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
114 mpegts_write_section(s, section, tot_len);
118 /*********************************************/
121 #define DEFAULT_PMT_START_PID 0x1000
122 #define DEFAULT_START_PID 0x0100
123 #define DEFAULT_PROVIDER_NAME "FFmpeg"
124 #define DEFAULT_SERVICE_NAME "Service01"
126 /* default network id, transport stream and service identifiers */
127 #define DEFAULT_ONID 0x0001
128 #define DEFAULT_TSID 0x0001
129 #define DEFAULT_SID 0x0001
131 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
132 #define DEFAULT_PES_HEADER_FREQ 16
133 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
135 /* we retransmit the SI info at this rate */
136 #define SDT_RETRANS_TIME 500
137 #define PAT_RETRANS_TIME 100
138 #define PCR_RETRANS_TIME 20
140 typedef struct MpegTSWriteStream {
141 struct MpegTSService *service;
142 int pid; /* stream associated pid */
146 uint8_t payload[DEFAULT_PES_PAYLOAD_SIZE];
149 typedef struct MpegTSService {
150 MpegTSSection pmt; /* MPEG2 pmt table context */
151 int sid; /* service ID */
155 int pcr_packet_count;
159 typedef struct MpegTSWrite {
160 MpegTSSection pat; /* MPEG2 pat table */
161 MpegTSSection sdt; /* MPEG2 sdt table context */
162 MpegTSService **services;
163 int sdt_packet_count;
165 int pat_packet_count;
172 static void mpegts_write_pat(AVFormatContext *s)
174 MpegTSWrite *ts = s->priv_data;
175 MpegTSService *service;
176 uint8_t data[1012], *q;
180 for(i = 0; i < ts->nb_services; i++) {
181 service = ts->services[i];
182 put16(&q, service->sid);
183 put16(&q, 0xe000 | service->pmt.pid);
185 mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
189 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
191 // MpegTSWrite *ts = s->priv_data;
192 uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
193 int val, stream_type, i;
196 put16(&q, 0xe000 | service->pcr_pid);
198 program_info_length_ptr = q;
199 q += 2; /* patched after */
201 /* put program info here */
203 val = 0xf000 | (q - program_info_length_ptr - 2);
204 program_info_length_ptr[0] = val >> 8;
205 program_info_length_ptr[1] = val;
207 for(i = 0; i < s->nb_streams; i++) {
208 AVStream *st = s->streams[i];
209 MpegTSWriteStream *ts_st = st->priv_data;
210 switch(st->codec->codec_id) {
211 case CODEC_ID_MPEG1VIDEO:
212 case CODEC_ID_MPEG2VIDEO:
213 stream_type = STREAM_TYPE_VIDEO_MPEG2;
216 stream_type = STREAM_TYPE_VIDEO_MPEG4;
219 stream_type = STREAM_TYPE_VIDEO_H264;
223 stream_type = STREAM_TYPE_AUDIO_MPEG1;
226 stream_type = STREAM_TYPE_AUDIO_AAC;
229 stream_type = STREAM_TYPE_AUDIO_AC3;
232 stream_type = STREAM_TYPE_PRIVATE_DATA;
236 put16(&q, 0xe000 | ts_st->pid);
238 q += 2; /* patched after */
240 /* write optional descriptors here */
241 switch(st->codec->codec_type) {
242 case CODEC_TYPE_AUDIO:
243 if (strlen(st->language) == 3) {
244 *q++ = 0x0a; /* ISO 639 language descriptor */
246 *q++ = st->language[0];
247 *q++ = st->language[1];
248 *q++ = st->language[2];
249 *q++ = 0; /* undefined type */
252 case CODEC_TYPE_SUBTITLE:
254 const char *language;
255 language = st->language;
256 if (strlen(language) != 3)
263 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
264 put16(&q, 1); /* page id */
265 put16(&q, 1); /* ancillary page id */
270 val = 0xf000 | (q - desc_length_ptr - 2);
271 desc_length_ptr[0] = val >> 8;
272 desc_length_ptr[1] = val;
274 mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
278 /* NOTE: str == NULL is accepted for an empty string */
279 static void putstr8(uint8_t **q_ptr, const char *str)
295 static void mpegts_write_sdt(AVFormatContext *s)
297 MpegTSWrite *ts = s->priv_data;
298 MpegTSService *service;
299 uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
300 int i, running_status, free_ca_mode, val;
305 for(i = 0; i < ts->nb_services; i++) {
306 service = ts->services[i];
307 put16(&q, service->sid);
308 *q++ = 0xfc | 0x00; /* currently no EIT info */
309 desc_list_len_ptr = q;
311 running_status = 4; /* running */
314 /* write only one descriptor for the service name and provider */
318 *q++ = 0x01; /* digital television service */
319 putstr8(&q, service->provider_name);
320 putstr8(&q, service->name);
321 desc_len_ptr[0] = q - desc_len_ptr - 1;
323 /* fill descriptor length */
324 val = (running_status << 13) | (free_ca_mode << 12) |
325 (q - desc_list_len_ptr - 2);
326 desc_list_len_ptr[0] = val >> 8;
327 desc_list_len_ptr[1] = val;
329 mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
333 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
335 const char *provider_name,
338 MpegTSService *service;
340 service = av_mallocz(sizeof(MpegTSService));
343 service->pmt.pid = DEFAULT_PMT_START_PID + ts->nb_services - 1;
345 service->provider_name = av_strdup(provider_name);
346 service->name = av_strdup(name);
347 service->pcr_pid = 0x1fff;
348 dynarray_add(&ts->services, &ts->nb_services, service);
352 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
354 AVFormatContext *ctx = s->opaque;
355 put_buffer(&ctx->pb, packet, TS_PACKET_SIZE);
358 static int mpegts_write_header(AVFormatContext *s)
360 MpegTSWrite *ts = s->priv_data;
361 MpegTSWriteStream *ts_st;
362 MpegTSService *service;
364 int i, total_bit_rate;
365 const char *service_name;
367 ts->tsid = DEFAULT_TSID;
368 ts->onid = DEFAULT_ONID;
369 /* allocate a single DVB service */
370 service_name = s->title;
371 if (service_name[0] == '\0')
372 service_name = DEFAULT_SERVICE_NAME;
373 service = mpegts_add_service(ts, DEFAULT_SID,
374 DEFAULT_PROVIDER_NAME, service_name);
375 service->pmt.write_packet = section_write_packet;
376 service->pmt.opaque = s;
378 ts->pat.pid = PAT_PID;
380 ts->pat.write_packet = section_write_packet;
383 ts->sdt.pid = SDT_PID;
385 ts->sdt.write_packet = section_write_packet;
388 /* assign pids to each stream */
390 for(i = 0;i < s->nb_streams; i++) {
392 ts_st = av_mallocz(sizeof(MpegTSWriteStream));
395 st->priv_data = ts_st;
396 ts_st->service = service;
397 ts_st->pid = DEFAULT_START_PID + i;
398 ts_st->payload_pts = AV_NOPTS_VALUE;
399 /* update PCR pid by using the first video stream */
400 if (st->codec->codec_type == CODEC_TYPE_VIDEO &&
401 service->pcr_pid == 0x1fff)
402 service->pcr_pid = ts_st->pid;
403 total_bit_rate += st->codec->bit_rate;
406 /* if no video stream, use the first stream as PCR */
407 if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
408 ts_st = s->streams[0]->priv_data;
409 service->pcr_pid = ts_st->pid;
412 if (total_bit_rate <= 8 * 1024)
413 total_bit_rate = 8 * 1024;
414 service->pcr_packet_freq = (total_bit_rate * PCR_RETRANS_TIME) /
415 (TS_PACKET_SIZE * 8 * 1000);
416 ts->sdt_packet_freq = (total_bit_rate * SDT_RETRANS_TIME) /
417 (TS_PACKET_SIZE * 8 * 1000);
418 ts->pat_packet_freq = (total_bit_rate * PAT_RETRANS_TIME) /
419 (TS_PACKET_SIZE * 8 * 1000);
422 total_bit_rate, ts->sdt_packet_freq, ts->pat_packet_freq);
425 /* write info at the start of the file, so that it will be fast to
429 for(i = 0; i < ts->nb_services; i++) {
430 mpegts_write_pmt(s, ts->services[i]);
432 put_flush_packet(&s->pb);
437 for(i = 0;i < s->nb_streams; i++) {
439 av_free(st->priv_data);
444 /* send SDT, PAT and PMT tables regulary */
445 static void retransmit_si_info(AVFormatContext *s)
447 MpegTSWrite *ts = s->priv_data;
450 if (++ts->sdt_packet_count == ts->sdt_packet_freq) {
451 ts->sdt_packet_count = 0;
454 if (++ts->pat_packet_count == ts->pat_packet_freq) {
455 ts->pat_packet_count = 0;
457 for(i = 0; i < ts->nb_services; i++) {
458 mpegts_write_pmt(s, ts->services[i]);
463 /* NOTE: pes_data contains all the PES packet */
464 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
465 const uint8_t *payload, int payload_size,
468 MpegTSWriteStream *ts_st = st->priv_data;
469 uint8_t buf[TS_PACKET_SIZE];
471 int val, is_start, len, header_len, write_pcr, private_code;
472 int afc_len, stuffing_len;
473 int64_t pcr = -1; /* avoid warning */
476 while (payload_size > 0) {
477 retransmit_si_info(s);
480 if (ts_st->pid == ts_st->service->pcr_pid) {
481 ts_st->service->pcr_packet_count++;
482 if (ts_st->service->pcr_packet_count >=
483 ts_st->service->pcr_packet_freq) {
484 ts_st->service->pcr_packet_count = 0;
486 /* XXX: this is incorrect, but at least we have a PCR
492 /* prepare packet header */
495 val = (ts_st->pid >> 8);
500 *q++ = 0x10 | ts_st->cc | (write_pcr ? 0x20 : 0);
501 ts_st->cc = (ts_st->cc + 1) & 0xf;
503 *q++ = 7; /* AFC length */
504 *q++ = 0x10; /* flags: PCR present */
509 *q++ = (pcr & 1) << 7;
513 /* write PES header */
518 if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
520 } else if (st->codec->codec_type == CODEC_TYPE_AUDIO &&
521 (st->codec->codec_id == CODEC_ID_MP2 ||
522 st->codec->codec_id == CODEC_ID_MP3)) {
526 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
530 if (pts != AV_NOPTS_VALUE)
534 if (private_code != 0)
536 len = payload_size + header_len;
540 /* data alignment indicator is required for subtitle data */
541 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE)
544 if (pts != AV_NOPTS_VALUE) {
545 *q++ = 0x80; /* PTS only */
546 *q++ = 0x05; /* header len */
548 (((pts >> 30) & 0x07) << 1) | 1;
550 val = (((pts >> 15) & 0x7fff) << 1) | 1;
553 val = (((pts) & 0x7fff) << 1) | 1;
560 if (private_code != 0)
565 header_len = q - buf;
567 len = TS_PACKET_SIZE - header_len;
568 if (len > payload_size)
570 stuffing_len = TS_PACKET_SIZE - header_len - len;
571 if (stuffing_len > 0) {
572 /* add stuffing with AFC */
574 /* stuffing already present: increase its size */
575 afc_len = buf[4] + 1;
576 memmove(buf + 4 + afc_len + stuffing_len,
578 header_len - (4 + afc_len));
579 buf[4] += stuffing_len;
580 memset(buf + 4 + afc_len, 0xff, stuffing_len);
583 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
585 buf[4] = stuffing_len - 1;
586 if (stuffing_len >= 2) {
588 memset(buf + 6, 0xff, stuffing_len - 2);
592 memcpy(buf + TS_PACKET_SIZE - len, payload, len);
595 put_buffer(&s->pb, buf, TS_PACKET_SIZE);
597 put_flush_packet(&s->pb);
600 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
602 AVStream *st = s->streams[pkt->stream_index];
604 uint8_t *buf= pkt->data;
605 MpegTSWriteStream *ts_st = st->priv_data;
606 int len, max_payload_size;
608 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
609 /* for subtitle, a single PES packet must be generated */
610 mpegts_write_pes(s, st, buf, size, pkt->pts);
614 max_payload_size = DEFAULT_PES_PAYLOAD_SIZE;
616 len = max_payload_size - ts_st->payload_index;
619 memcpy(ts_st->payload + ts_st->payload_index, buf, len);
622 ts_st->payload_index += len;
623 if (ts_st->payload_pts == AV_NOPTS_VALUE)
624 ts_st->payload_pts = pkt->pts;
625 if (ts_st->payload_index >= max_payload_size) {
626 mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
628 ts_st->payload_pts = AV_NOPTS_VALUE;
629 ts_st->payload_index = 0;
635 static int mpegts_write_end(AVFormatContext *s)
637 MpegTSWrite *ts = s->priv_data;
638 MpegTSWriteStream *ts_st;
639 MpegTSService *service;
643 /* flush current packets */
644 for(i = 0; i < s->nb_streams; i++) {
646 ts_st = st->priv_data;
647 if (ts_st->payload_index > 0) {
648 mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
652 put_flush_packet(&s->pb);
654 for(i = 0; i < ts->nb_services; i++) {
655 service = ts->services[i];
656 av_freep(&service->provider_name);
657 av_freep(&service->name);
660 av_free(ts->services);
665 AVOutputFormat mpegts_muxer = {
667 "MPEG2 transport stream format",