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
22 #include "libavutil/crc.h"
26 /* write DVB SI sections */
28 /*********************************************/
29 /* mpegts section writer */
31 typedef struct MpegTSSection {
34 void (*write_packet)(struct MpegTSSection *s, const uint8_t *packet);
38 /* NOTE: 4 bytes must be left at the end for the crc32 */
39 static void mpegts_write_section(MpegTSSection *s, uint8_t *buf, int len)
42 unsigned char packet[TS_PACKET_SIZE];
43 const unsigned char *buf_ptr;
45 int first, b, len1, left;
47 crc = bswap_32(av_crc(av_crc_get_table(AV_CRC_32_IEEE), -1, buf, len - 4));
48 buf[len - 4] = (crc >> 24) & 0xff;
49 buf[len - 3] = (crc >> 16) & 0xff;
50 buf[len - 2] = (crc >> 8) & 0xff;
51 buf[len - 1] = (crc) & 0xff;
53 /* send each packet */
56 first = (buf == buf_ptr);
65 s->cc = (s->cc + 1) & 0xf;
67 *q++ = 0; /* 0 offset */
68 len1 = TS_PACKET_SIZE - (q - packet);
71 memcpy(q, buf_ptr, len1);
73 /* add known padding data */
74 left = TS_PACKET_SIZE - (q - packet);
76 memset(q, 0xff, left);
78 s->write_packet(s, packet);
85 static inline void put16(uint8_t **q_ptr, int val)
94 static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
95 int version, int sec_num, int last_sec_num,
96 uint8_t *buf, int len)
98 uint8_t section[1024], *q;
101 tot_len = 3 + 5 + len + 4;
102 /* check if not too big */
108 put16(&q, 0xb000 | (len + 5 + 4)); /* 5 byte header + 4 byte CRC */
110 *q++ = 0xc1 | (version << 1); /* current_next_indicator = 1 */
115 mpegts_write_section(s, section, tot_len);
119 /*********************************************/
122 #define DEFAULT_PMT_START_PID 0x1000
123 #define DEFAULT_START_PID 0x0100
124 #define DEFAULT_PROVIDER_NAME "FFmpeg"
125 #define DEFAULT_SERVICE_NAME "Service01"
127 /* default network id, transport stream and service identifiers */
128 #define DEFAULT_ONID 0x0001
129 #define DEFAULT_TSID 0x0001
130 #define DEFAULT_SID 0x0001
132 /* a PES packet header is generated every DEFAULT_PES_HEADER_FREQ packets */
133 #define DEFAULT_PES_HEADER_FREQ 16
134 #define DEFAULT_PES_PAYLOAD_SIZE ((DEFAULT_PES_HEADER_FREQ - 1) * 184 + 170)
136 /* we retransmit the SI info at this rate */
137 #define SDT_RETRANS_TIME 500
138 #define PAT_RETRANS_TIME 100
139 #define PCR_RETRANS_TIME 20
141 typedef struct MpegTSWriteStream {
142 struct MpegTSService *service;
143 int pid; /* stream associated pid */
148 uint8_t payload[DEFAULT_PES_PAYLOAD_SIZE];
151 typedef struct MpegTSService {
152 MpegTSSection pmt; /* MPEG2 pmt table context */
153 int sid; /* service ID */
157 int pcr_packet_count;
161 typedef struct MpegTSWrite {
162 MpegTSSection pat; /* MPEG2 pat table */
163 MpegTSSection sdt; /* MPEG2 sdt table context */
164 MpegTSService **services;
165 int sdt_packet_count;
167 int pat_packet_count;
174 static void mpegts_write_pat(AVFormatContext *s)
176 MpegTSWrite *ts = s->priv_data;
177 MpegTSService *service;
178 uint8_t data[1012], *q;
182 for(i = 0; i < ts->nb_services; i++) {
183 service = ts->services[i];
184 put16(&q, service->sid);
185 put16(&q, 0xe000 | service->pmt.pid);
187 mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid, 0, 0, 0,
191 static void mpegts_write_pmt(AVFormatContext *s, MpegTSService *service)
193 // MpegTSWrite *ts = s->priv_data;
194 uint8_t data[1012], *q, *desc_length_ptr, *program_info_length_ptr;
195 int val, stream_type, i;
198 put16(&q, 0xe000 | service->pcr_pid);
200 program_info_length_ptr = q;
201 q += 2; /* patched after */
203 /* put program info here */
205 val = 0xf000 | (q - program_info_length_ptr - 2);
206 program_info_length_ptr[0] = val >> 8;
207 program_info_length_ptr[1] = val;
209 for(i = 0; i < s->nb_streams; i++) {
210 AVStream *st = s->streams[i];
211 MpegTSWriteStream *ts_st = st->priv_data;
212 switch(st->codec->codec_id) {
213 case CODEC_ID_MPEG1VIDEO:
214 case CODEC_ID_MPEG2VIDEO:
215 stream_type = STREAM_TYPE_VIDEO_MPEG2;
218 stream_type = STREAM_TYPE_VIDEO_MPEG4;
221 stream_type = STREAM_TYPE_VIDEO_H264;
225 stream_type = STREAM_TYPE_AUDIO_MPEG1;
228 stream_type = STREAM_TYPE_AUDIO_AAC;
231 stream_type = STREAM_TYPE_AUDIO_AC3;
234 stream_type = STREAM_TYPE_PRIVATE_DATA;
238 put16(&q, 0xe000 | ts_st->pid);
240 q += 2; /* patched after */
242 /* write optional descriptors here */
243 switch(st->codec->codec_type) {
244 case CODEC_TYPE_AUDIO:
245 if (strlen(st->language) == 3) {
246 *q++ = 0x0a; /* ISO 639 language descriptor */
248 *q++ = st->language[0];
249 *q++ = st->language[1];
250 *q++ = st->language[2];
251 *q++ = 0; /* undefined type */
254 case CODEC_TYPE_SUBTITLE:
256 const char *language;
257 language = st->language;
258 if (strlen(language) != 3)
265 *q++ = 0x10; /* normal subtitles (0x20 = if hearing pb) */
266 put16(&q, 1); /* page id */
267 put16(&q, 1); /* ancillary page id */
272 val = 0xf000 | (q - desc_length_ptr - 2);
273 desc_length_ptr[0] = val >> 8;
274 desc_length_ptr[1] = val;
276 mpegts_write_section1(&service->pmt, PMT_TID, service->sid, 0, 0, 0,
280 /* NOTE: str == NULL is accepted for an empty string */
281 static void putstr8(uint8_t **q_ptr, const char *str)
297 static void mpegts_write_sdt(AVFormatContext *s)
299 MpegTSWrite *ts = s->priv_data;
300 MpegTSService *service;
301 uint8_t data[1012], *q, *desc_list_len_ptr, *desc_len_ptr;
302 int i, running_status, free_ca_mode, val;
307 for(i = 0; i < ts->nb_services; i++) {
308 service = ts->services[i];
309 put16(&q, service->sid);
310 *q++ = 0xfc | 0x00; /* currently no EIT info */
311 desc_list_len_ptr = q;
313 running_status = 4; /* running */
316 /* write only one descriptor for the service name and provider */
320 *q++ = 0x01; /* digital television service */
321 putstr8(&q, service->provider_name);
322 putstr8(&q, service->name);
323 desc_len_ptr[0] = q - desc_len_ptr - 1;
325 /* fill descriptor length */
326 val = (running_status << 13) | (free_ca_mode << 12) |
327 (q - desc_list_len_ptr - 2);
328 desc_list_len_ptr[0] = val >> 8;
329 desc_list_len_ptr[1] = val;
331 mpegts_write_section1(&ts->sdt, SDT_TID, ts->tsid, 0, 0, 0,
335 static MpegTSService *mpegts_add_service(MpegTSWrite *ts,
337 const char *provider_name,
340 MpegTSService *service;
342 service = av_mallocz(sizeof(MpegTSService));
345 service->pmt.pid = DEFAULT_PMT_START_PID + ts->nb_services - 1;
347 service->provider_name = av_strdup(provider_name);
348 service->name = av_strdup(name);
349 service->pcr_pid = 0x1fff;
350 dynarray_add(&ts->services, &ts->nb_services, service);
354 static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
356 AVFormatContext *ctx = s->opaque;
357 put_buffer(ctx->pb, packet, TS_PACKET_SIZE);
360 static int mpegts_write_header(AVFormatContext *s)
362 MpegTSWrite *ts = s->priv_data;
363 MpegTSWriteStream *ts_st;
364 MpegTSService *service;
366 int i, total_bit_rate;
367 const char *service_name;
369 ts->tsid = DEFAULT_TSID;
370 ts->onid = DEFAULT_ONID;
371 /* allocate a single DVB service */
372 service_name = s->title;
373 if (service_name[0] == '\0')
374 service_name = DEFAULT_SERVICE_NAME;
375 service = mpegts_add_service(ts, DEFAULT_SID,
376 DEFAULT_PROVIDER_NAME, service_name);
377 service->pmt.write_packet = section_write_packet;
378 service->pmt.opaque = s;
380 ts->pat.pid = PAT_PID;
382 ts->pat.write_packet = section_write_packet;
385 ts->sdt.pid = SDT_PID;
387 ts->sdt.write_packet = section_write_packet;
390 /* assign pids to each stream */
392 for(i = 0;i < s->nb_streams; i++) {
394 ts_st = av_mallocz(sizeof(MpegTSWriteStream));
397 st->priv_data = ts_st;
398 ts_st->service = service;
399 ts_st->pid = DEFAULT_START_PID + i;
400 ts_st->payload_pts = AV_NOPTS_VALUE;
401 ts_st->payload_dts = AV_NOPTS_VALUE;
402 /* update PCR pid by using the first video stream */
403 if (st->codec->codec_type == CODEC_TYPE_VIDEO &&
404 service->pcr_pid == 0x1fff)
405 service->pcr_pid = ts_st->pid;
406 total_bit_rate += st->codec->bit_rate;
409 /* if no video stream, use the first stream as PCR */
410 if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
411 ts_st = s->streams[0]->priv_data;
412 service->pcr_pid = ts_st->pid;
415 if (total_bit_rate <= 8 * 1024)
416 total_bit_rate = 8 * 1024;
417 service->pcr_packet_freq = (total_bit_rate * PCR_RETRANS_TIME) /
418 (TS_PACKET_SIZE * 8 * 1000);
419 ts->sdt_packet_freq = (total_bit_rate * SDT_RETRANS_TIME) /
420 (TS_PACKET_SIZE * 8 * 1000);
421 ts->pat_packet_freq = (total_bit_rate * PAT_RETRANS_TIME) /
422 (TS_PACKET_SIZE * 8 * 1000);
425 total_bit_rate, ts->sdt_packet_freq, ts->pat_packet_freq);
428 /* write info at the start of the file, so that it will be fast to
432 for(i = 0; i < ts->nb_services; i++) {
433 mpegts_write_pmt(s, ts->services[i]);
435 put_flush_packet(s->pb);
440 for(i = 0;i < s->nb_streams; i++) {
442 av_free(st->priv_data);
447 /* send SDT, PAT and PMT tables regulary */
448 static void retransmit_si_info(AVFormatContext *s)
450 MpegTSWrite *ts = s->priv_data;
453 if (++ts->sdt_packet_count == ts->sdt_packet_freq) {
454 ts->sdt_packet_count = 0;
457 if (++ts->pat_packet_count == ts->pat_packet_freq) {
458 ts->pat_packet_count = 0;
460 for(i = 0; i < ts->nb_services; i++) {
461 mpegts_write_pmt(s, ts->services[i]);
466 static void write_pts(uint8_t *q, int fourbits, int64_t pts)
470 val = fourbits << 4 | (((pts >> 30) & 0x07) << 1) | 1;
472 val = (((pts >> 15) & 0x7fff) << 1) | 1;
475 val = (((pts) & 0x7fff) << 1) | 1;
480 /* NOTE: pes_data contains all the PES packet */
481 static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
482 const uint8_t *payload, int payload_size,
483 int64_t pts, int64_t dts)
485 MpegTSWriteStream *ts_st = st->priv_data;
486 uint8_t buf[TS_PACKET_SIZE];
488 int val, is_start, len, header_len, write_pcr, private_code, flags;
489 int afc_len, stuffing_len;
490 int64_t pcr = -1; /* avoid warning */
493 while (payload_size > 0) {
494 retransmit_si_info(s);
497 if (ts_st->pid == ts_st->service->pcr_pid) {
498 ts_st->service->pcr_packet_count++;
499 if (ts_st->service->pcr_packet_count >=
500 ts_st->service->pcr_packet_freq) {
501 ts_st->service->pcr_packet_count = 0;
503 /* XXX: this is incorrect, but at least we have a PCR
509 /* prepare packet header */
512 val = (ts_st->pid >> 8);
517 *q++ = 0x10 | ts_st->cc | (write_pcr ? 0x20 : 0);
518 ts_st->cc = (ts_st->cc + 1) & 0xf;
520 *q++ = 7; /* AFC length */
521 *q++ = 0x10; /* flags: PCR present */
526 *q++ = (pcr & 1) << 7;
530 /* write PES header */
535 if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
537 } else if (st->codec->codec_type == CODEC_TYPE_AUDIO &&
538 (st->codec->codec_id == CODEC_ID_MP2 ||
539 st->codec->codec_id == CODEC_ID_MP3)) {
543 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
549 if (pts != AV_NOPTS_VALUE) {
553 if (dts != AV_NOPTS_VALUE) {
557 len = payload_size + header_len + 3;
558 if (private_code != 0)
563 /* data alignment indicator is required for subtitle data */
564 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE)
569 if (pts != AV_NOPTS_VALUE) {
570 write_pts(q, flags >> 6, pts);
573 if (dts != AV_NOPTS_VALUE) {
574 write_pts(q, 1, dts);
577 if (private_code != 0)
582 header_len = q - buf;
584 len = TS_PACKET_SIZE - header_len;
585 if (len > payload_size)
587 stuffing_len = TS_PACKET_SIZE - header_len - len;
588 if (stuffing_len > 0) {
589 /* add stuffing with AFC */
591 /* stuffing already present: increase its size */
592 afc_len = buf[4] + 1;
593 memmove(buf + 4 + afc_len + stuffing_len,
595 header_len - (4 + afc_len));
596 buf[4] += stuffing_len;
597 memset(buf + 4 + afc_len, 0xff, stuffing_len);
600 memmove(buf + 4 + stuffing_len, buf + 4, header_len - 4);
602 buf[4] = stuffing_len - 1;
603 if (stuffing_len >= 2) {
605 memset(buf + 6, 0xff, stuffing_len - 2);
609 memcpy(buf + TS_PACKET_SIZE - len, payload, len);
612 put_buffer(s->pb, buf, TS_PACKET_SIZE);
614 put_flush_packet(s->pb);
617 static int mpegts_write_packet(AVFormatContext *s, AVPacket *pkt)
619 AVStream *st = s->streams[pkt->stream_index];
621 uint8_t *buf= pkt->data;
622 MpegTSWriteStream *ts_st = st->priv_data;
623 int len, max_payload_size;
625 if (st->codec->codec_type == CODEC_TYPE_SUBTITLE) {
626 /* for subtitle, a single PES packet must be generated */
627 mpegts_write_pes(s, st, buf, size, pkt->pts, AV_NOPTS_VALUE);
631 max_payload_size = DEFAULT_PES_PAYLOAD_SIZE;
633 len = max_payload_size - ts_st->payload_index;
636 memcpy(ts_st->payload + ts_st->payload_index, buf, len);
639 ts_st->payload_index += len;
640 if (ts_st->payload_pts == AV_NOPTS_VALUE)
641 ts_st->payload_pts = pkt->pts;
642 if (ts_st->payload_dts == AV_NOPTS_VALUE)
643 ts_st->payload_dts = pkt->dts;
644 if (ts_st->payload_index >= max_payload_size) {
645 mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
646 ts_st->payload_pts, ts_st->payload_dts);
647 ts_st->payload_pts = AV_NOPTS_VALUE;
648 ts_st->payload_dts = AV_NOPTS_VALUE;
649 ts_st->payload_index = 0;
655 static int mpegts_write_end(AVFormatContext *s)
657 MpegTSWrite *ts = s->priv_data;
658 MpegTSWriteStream *ts_st;
659 MpegTSService *service;
663 /* flush current packets */
664 for(i = 0; i < s->nb_streams; i++) {
666 ts_st = st->priv_data;
667 if (ts_st->payload_index > 0) {
668 mpegts_write_pes(s, st, ts_st->payload, ts_st->payload_index,
669 ts_st->payload_pts, ts_st->payload_dts);
672 put_flush_packet(s->pb);
674 for(i = 0; i < ts->nb_services; i++) {
675 service = ts->services[i];
676 av_freep(&service->provider_name);
677 av_freep(&service->name);
680 av_free(ts->services);
685 AVOutputFormat mpegts_muxer = {
687 NULL_IF_CONFIG_SMALL("MPEG-2 transport stream format"),