3 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
5 * This file is part of Libav.
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 /*********************************************/
32 #define MAX_SYNC_SIZE 100000
34 static int check_pes(uint8_t *p, uint8_t *end)
37 int pes2 = (p[3] & 0xC0) == 0x80 &&
38 (p[4] & 0xC0) != 0x40 &&
39 ((p[4] & 0xC0) == 0x00 ||
40 (p[4] & 0xC0) >> 2 == (p[6] & 0xF0));
42 for (p += 3; p < end && *p == 0xFF; p++) ;
43 if ((*p & 0xC0) == 0x40)
46 if ((*p & 0xF0) == 0x20)
47 pes1 = p[0] & p[2] & p[4] & 1;
48 else if ((*p & 0xF0) == 0x30)
49 pes1 = p[0] & p[2] & p[4] & p[5] & p[7] & p[9] & 1;
56 static int check_pack_header(const uint8_t *buf)
58 return (buf[1] & 0xC0) == 0x40 || (buf[1] & 0xF0) == 0x20;
61 static int mpegps_probe(AVProbeData *p)
65 int sys = 0, pspack = 0, priv1 = 0, vid = 0;
66 int audio = 0, invalid = 0, score = 0;
68 for (i = 0; i < p->buf_size; i++) {
69 code = (code << 8) + p->buf[i];
70 if ((code & 0xffffff00) == 0x100) {
71 int len = p->buf[i + 1] << 8 | p->buf[i + 2];
72 int pes = check_pes(p->buf + i, p->buf + p->buf_size);
73 int pack = check_pack_header(p->buf + i);
75 if (code == SYSTEM_HEADER_START_CODE)
77 else if (code == PACK_START_CODE && pack)
79 else if ((code & 0xf0) == VIDEO_ID && pes)
81 // skip pes payload to avoid start code emulation for private
83 else if ((code & 0xe0) == AUDIO_ID && pes) {
86 } else if (code == PRIVATE_STREAM_1 && pes) {
89 } else if ((code & 0xf0) == VIDEO_ID && !pes)
91 else if ((code & 0xe0) == AUDIO_ID && !pes)
93 else if (code == PRIVATE_STREAM_1 && !pes)
98 if (vid + audio > invalid) /* invalid VDR files nd short PES streams */
99 score = AVPROBE_SCORE_EXTENSION / 2;
101 if (sys > invalid && sys * 9 <= pspack * 10)
102 return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2
103 : AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg
104 if (pspack > invalid && (priv1 + vid + audio) * 10 >= pspack * 9)
105 return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2
106 : AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg
107 if ((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys &&
108 !pspack && p->buf_size > 2048 && vid + audio > invalid) /* PES stream */
109 return (audio > 12 || vid > 3) ? AVPROBE_SCORE_EXTENSION + 2
110 : AVPROBE_SCORE_EXTENSION / 2;
112 // 02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1
113 // mp3_misidentified_2.mp3 has sys:0 priv1:0 pspack:0 vid:0 audio:6
117 typedef struct MpegDemuxContext {
118 int32_t header_state;
119 unsigned char psm_es_type[256];
123 static int mpegps_read_header(AVFormatContext *s)
125 MpegDemuxContext *m = s->priv_data;
126 const char *sofdec = "Sofdec";
129 m->header_state = 0xff;
130 s->ctx_flags |= AVFMTCTX_NOHEADER;
135 m->header_state = m->header_state << 8 | v;
137 } while (v == sofdec[i] && i++ < 6);
139 m->sofdec = (m->sofdec == 6) ? 1 : 0;
141 /* no need to do more */
145 static int64_t get_pts(AVIOContext *pb, int c)
149 buf[0] = c < 0 ? avio_r8(pb) : c;
150 avio_read(pb, buf + 1, 4);
152 return ff_parse_pes_pts(buf);
155 static int find_next_start_code(AVIOContext *pb, int *size_ptr,
156 int32_t *header_state)
158 unsigned int state, v;
161 state = *header_state;
168 if (state == 0x000001) {
169 state = ((state << 8) | v) & 0xffffff;
173 state = ((state << 8) | v) & 0xffffff;
178 *header_state = state;
184 * Extract stream types from a program stream map
185 * According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35
187 * @return number of bytes occupied by PSM in the bitstream
189 static long mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)
191 int psm_length, ps_info_length, es_map_length;
193 psm_length = avio_rb16(pb);
196 ps_info_length = avio_rb16(pb);
198 /* skip program_stream_info */
199 avio_skip(pb, ps_info_length);
200 es_map_length = avio_rb16(pb);
202 /* at least one es available? */
203 while (es_map_length >= 4) {
204 unsigned char type = avio_r8(pb);
205 unsigned char es_id = avio_r8(pb);
206 uint16_t es_info_length = avio_rb16(pb);
208 /* remember mapping from stream id to stream type */
209 m->psm_es_type[es_id] = type;
210 /* skip program_stream_info */
211 avio_skip(pb, es_info_length);
212 es_map_length -= 4 + es_info_length;
214 avio_rb32(pb); /* crc32 */
215 return 2 + psm_length;
218 /* read the next PES header. Return its position in ppos
219 * (if not NULL), and its start code, pts and dts.
221 static int mpegps_read_pes_header(AVFormatContext *s,
222 int64_t *ppos, int *pstart_code,
223 int64_t *ppts, int64_t *pdts)
225 MpegDemuxContext *m = s->priv_data;
226 int len, size, startcode, c, flags, header_len;
227 int pes_ext, ext2_len, id_ext, skip;
229 int64_t last_sync = avio_tell(s->pb);
232 avio_seek(s->pb, last_sync, SEEK_SET);
234 /* next start code (should be immediately after) */
235 m->header_state = 0xff;
236 size = MAX_SYNC_SIZE;
237 startcode = find_next_start_code(s->pb, &size, &m->header_state);
238 last_sync = avio_tell(s->pb);
240 if (s->pb->eof_reached)
242 // FIXME we should remember header_state
243 return AVERROR(EAGAIN);
246 if (startcode == PACK_START_CODE)
248 if (startcode == SYSTEM_HEADER_START_CODE)
250 if (startcode == PADDING_STREAM) {
251 avio_skip(s->pb, avio_rb16(s->pb));
254 if (startcode == PRIVATE_STREAM_2) {
255 len = avio_rb16(s->pb);
258 if (avio_r8(s->pb) == 'S') {
260 avio_read(s->pb, buf, sizeof(buf));
261 m->sofdec = !memcmp(buf, "ofdec", 5);
266 m->sofdec -= !m->sofdec;
268 avio_skip(s->pb, len);
271 if (startcode == PROGRAM_STREAM_MAP) {
272 mpegps_psm_parse(m, s->pb);
276 /* find matching stream */
277 if (!((startcode >= 0x1c0 && startcode <= 0x1df) ||
278 (startcode >= 0x1e0 && startcode <= 0x1ef) ||
279 (startcode == 0x1bd) || (startcode == 0x1fd)))
282 *ppos = avio_tell(s->pb) - 4;
284 len = avio_rb16(s->pb);
286 dts = AV_NOPTS_VALUE;
293 /* XXX: for mpeg1, should test only bit 7 */
297 if ((c & 0xc0) == 0x40) {
298 /* buffer scale & size */
303 if ((c & 0xe0) == 0x20) {
305 pts = get_pts(s->pb, c);
308 dts = get_pts(s->pb, -1);
311 } else if ((c & 0xc0) == 0x80) {
313 flags = avio_r8(s->pb);
314 header_len = avio_r8(s->pb);
316 if (header_len > len)
320 dts = pts = get_pts(s->pb, -1);
323 dts = get_pts(s->pb, -1);
327 if (flags & 0x3f && header_len == 0) {
329 av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n");
331 if (flags & 0x01) { /* PES extension */
332 pes_ext = avio_r8(s->pb);
334 /* Skip PES private data, program packet sequence counter
335 * and P-STD buffer */
336 skip = (pes_ext >> 4) & 0xb;
338 if (pes_ext & 0x40 || skip > header_len) {
339 av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext);
342 avio_skip(s->pb, skip);
345 if (pes_ext & 0x01) { /* PES extension 2 */
346 ext2_len = avio_r8(s->pb);
348 if ((ext2_len & 0x7f) > 0) {
349 id_ext = avio_r8(s->pb);
350 if ((id_ext & 0x80) == 0)
351 startcode = ((startcode & 0xff) << 8) | id_ext;
358 avio_skip(s->pb, header_len);
362 if (startcode == PRIVATE_STREAM_1 && !m->psm_es_type[startcode & 0xff]) {
363 startcode = avio_r8(s->pb);
365 if (startcode >= 0x80 && startcode <= 0xcf) {
366 /* audio: skip header */
371 if (startcode >= 0xb0 && startcode <= 0xbf) {
372 /* MLP/TrueHD audio has a 4-byte header */
380 if (dts != AV_NOPTS_VALUE && ppos) {
382 for (i = 0; i < s->nb_streams; i++) {
383 if (startcode == s->streams[i]->id &&
384 s->pb->seekable /* index useless on streams anyway */) {
385 ff_reduce_index(s, i);
386 av_add_index_entry(s->streams[i], *ppos, dts, 0, 0,
387 AVINDEX_KEYFRAME /* FIXME keyframe? */);
392 *pstart_code = startcode;
398 static int mpegps_read_packet(AVFormatContext *s,
401 MpegDemuxContext *m = s->priv_data;
403 int len, startcode, i, es_type, ret;
404 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
405 enum AVMediaType type;
406 int64_t pts, dts, dummy_pos; // dummy_pos is needed for the index building to work
407 uint8_t av_uninit(dvdaudio_substream_type);
410 len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts);
414 if (startcode == 0x1bd) {
415 dvdaudio_substream_type = avio_r8(s->pb);
420 /* now find stream */
421 for (i = 0; i < s->nb_streams; i++) {
423 if (st->id == startcode)
427 es_type = m->psm_es_type[startcode & 0xff];
428 if (es_type > 0 && es_type != STREAM_TYPE_PRIVATE_DATA) {
429 if (es_type == STREAM_TYPE_VIDEO_MPEG1) {
430 codec_id = AV_CODEC_ID_MPEG2VIDEO;
431 type = AVMEDIA_TYPE_VIDEO;
432 } else if (es_type == STREAM_TYPE_VIDEO_MPEG2) {
433 codec_id = AV_CODEC_ID_MPEG2VIDEO;
434 type = AVMEDIA_TYPE_VIDEO;
435 } else if (es_type == STREAM_TYPE_AUDIO_MPEG1 ||
436 es_type == STREAM_TYPE_AUDIO_MPEG2) {
437 codec_id = AV_CODEC_ID_MP3;
438 type = AVMEDIA_TYPE_AUDIO;
439 } else if (es_type == STREAM_TYPE_AUDIO_AAC) {
440 codec_id = AV_CODEC_ID_AAC;
441 type = AVMEDIA_TYPE_AUDIO;
442 } else if (es_type == STREAM_TYPE_VIDEO_MPEG4) {
443 codec_id = AV_CODEC_ID_MPEG4;
444 type = AVMEDIA_TYPE_VIDEO;
445 } else if (es_type == STREAM_TYPE_VIDEO_H264) {
446 codec_id = AV_CODEC_ID_H264;
447 type = AVMEDIA_TYPE_VIDEO;
448 } else if (es_type == STREAM_TYPE_AUDIO_AC3) {
449 codec_id = AV_CODEC_ID_AC3;
450 type = AVMEDIA_TYPE_AUDIO;
454 } else if (startcode >= 0x1e0 && startcode <= 0x1ef) {
455 static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };
456 unsigned char buf[8];
458 avio_read(s->pb, buf, 8);
459 avio_seek(s->pb, -8, SEEK_CUR);
460 if (!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1))
461 codec_id = AV_CODEC_ID_CAVS;
463 codec_id = AV_CODEC_ID_PROBE;
464 type = AVMEDIA_TYPE_VIDEO;
465 } else if (startcode >= 0x1c0 && startcode <= 0x1df) {
466 type = AVMEDIA_TYPE_AUDIO;
467 codec_id = m->sofdec > 0 ? AV_CODEC_ID_ADPCM_ADX : AV_CODEC_ID_MP2;
468 } else if (startcode >= 0x80 && startcode <= 0x87) {
469 type = AVMEDIA_TYPE_AUDIO;
470 codec_id = AV_CODEC_ID_AC3;
471 } else if ((startcode >= 0x88 && startcode <= 0x8f) ||
472 (startcode >= 0x98 && startcode <= 0x9f)) {
473 /* 0x90 - 0x97 is reserved for SDDS in DVD specs */
474 type = AVMEDIA_TYPE_AUDIO;
475 codec_id = AV_CODEC_ID_DTS;
476 } else if (startcode >= 0xa0 && startcode <= 0xaf) {
477 type = AVMEDIA_TYPE_AUDIO;
478 codec_id = AV_CODEC_ID_PCM_DVD;
479 } else if (startcode >= 0xb0 && startcode <= 0xbf) {
480 type = AVMEDIA_TYPE_AUDIO;
481 codec_id = AV_CODEC_ID_TRUEHD;
482 } else if (startcode >= 0xc0 && startcode <= 0xcf) {
483 /* Used for both AC-3 and E-AC-3 in EVOB files */
484 type = AVMEDIA_TYPE_AUDIO;
485 codec_id = AV_CODEC_ID_AC3;
486 } else if (startcode >= 0x20 && startcode <= 0x3f) {
487 type = AVMEDIA_TYPE_SUBTITLE;
488 codec_id = AV_CODEC_ID_DVD_SUBTITLE;
489 } else if (startcode >= 0xfd55 && startcode <= 0xfd5f) {
490 type = AVMEDIA_TYPE_VIDEO;
491 codec_id = AV_CODEC_ID_VC1;
492 } else if (startcode == 0x1bd) {
493 // check dvd audio substream type
494 type = AVMEDIA_TYPE_AUDIO;
495 switch (dvdaudio_substream_type & 0xe0) {
497 codec_id = AV_CODEC_ID_PCM_DVD;
500 if ((dvdaudio_substream_type & 0xf8) == 0x88)
501 codec_id = AV_CODEC_ID_DTS;
503 codec_id = AV_CODEC_ID_AC3;
506 av_log(s, AV_LOG_ERROR, "Unknown 0x1bd sub-stream\n");
512 avio_skip(s->pb, len);
515 /* no stream found: add a new stream */
516 st = avformat_new_stream(s, NULL);
520 st->codec->codec_type = type;
521 st->codec->codec_id = codec_id;
522 st->need_parsing = AVSTREAM_PARSE_FULL;
525 if (st->discard >= AVDISCARD_ALL)
527 ret = av_get_packet(s->pb, pkt, len);
531 pkt->pos = dummy_pos;
532 pkt->stream_index = st->index;
533 av_dlog(s, "%d: pts=%0.3f dts=%0.3f size=%d\n",
534 pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0,
537 return (ret < 0) ? ret : 0;
540 static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index,
541 int64_t *ppos, int64_t pos_limit)
544 int64_t pos, pts, dts;
547 if (avio_seek(s->pb, pos, SEEK_SET) < 0)
548 return AV_NOPTS_VALUE;
551 len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts);
553 av_dlog(s, "none (ret=%d)\n", len);
554 return AV_NOPTS_VALUE;
556 if (startcode == s->streams[stream_index]->id &&
557 dts != AV_NOPTS_VALUE) {
560 avio_skip(s->pb, len);
562 av_dlog(s, "pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n",
563 pos, dts, dts / 90000.0);
568 AVInputFormat ff_mpegps_demuxer = {
570 .long_name = NULL_IF_CONFIG_SMALL("MPEG-PS (MPEG-2 Program Stream)"),
571 .priv_data_size = sizeof(MpegDemuxContext),
572 .read_probe = mpegps_probe,
573 .read_header = mpegps_read_header,
574 .read_packet = mpegps_read_packet,
575 .read_timestamp = mpegps_read_dts,
576 .flags = AVFMT_SHOW_IDS | AVFMT_TS_DISCONT,