1 /*
2 * MPEG-1/2 demuxer
3 * Copyright (c) 2000, 2001, 2002 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
22 #include "config_components.h"
23
24 #include "libavutil/channel_layout.h"
25 #include "avformat.h"
26 #include "avio_internal.h"
27 #include "demux.h"
28 #include "internal.h"
29 #include "mpeg.h"
30
31 /*********************************************/
32 /* demux code */
33
34 #define MAX_SYNC_SIZE 100000
35
check_pes(const uint8_t *p, const uint8_t *end)36 static int check_pes(const uint8_t *p, const uint8_t *end)
37 {
38 int pes1;
39 int pes2 = (p[3] & 0xC0) == 0x80 &&
40 (p[4] & 0xC0) != 0x40 &&
41 ((p[4] & 0xC0) == 0x00 ||
42 (p[4] & 0xC0) >> 2 == (p[6] & 0xF0));
43
44 for (p += 3; p < end && *p == 0xFF; p++) ;
45 if ((*p & 0xC0) == 0x40)
46 p += 2;
47
48 if ((*p & 0xF0) == 0x20)
49 pes1 = p[0] & p[2] & p[4] & 1;
50 else if ((*p & 0xF0) == 0x30)
51 pes1 = p[0] & p[2] & p[4] & p[5] & p[7] & p[9] & 1;
52 else
53 pes1 = *p == 0x0F;
54
55 return pes1 || pes2;
56 }
57
check_pack_header(const uint8_t *buf)58 static int check_pack_header(const uint8_t *buf)
59 {
60 return (buf[1] & 0xC0) == 0x40 || (buf[1] & 0xF0) == 0x20;
61 }
62
mpegps_probe(const AVProbeData *p)63 static int mpegps_probe(const AVProbeData *p)
64 {
65 uint32_t code = -1;
66 int i;
67 int sys = 0, pspack = 0, priv1 = 0, vid = 0;
68 int audio = 0, invalid = 0, score = 0;
69 int endpes = 0;
70
71 for (i = 0; i < p->buf_size; i++) {
72 code = (code << 8) + p->buf[i];
73 if ((code & 0xffffff00) == 0x100) {
74 int len = p->buf[i + 1] << 8 | p->buf[i + 2];
75 int pes = endpes <= i && check_pes(p->buf + i, p->buf + p->buf_size);
76 int pack = check_pack_header(p->buf + i);
77
78 if (code == SYSTEM_HEADER_START_CODE)
79 sys++;
80 else if (code == PACK_START_CODE && pack)
81 pspack++;
82 else if ((code & 0xf0) == VIDEO_ID && pes) {
83 endpes = i + len;
84 vid++;
85 }
86 // skip pes payload to avoid start code emulation for private
87 // and audio streams
88 else if ((code & 0xe0) == AUDIO_ID && pes) {audio++; i+=len;}
89 else if (code == PRIVATE_STREAM_1 && pes) {priv1++; i+=len;}
90 else if (code == 0x1fd && pes) vid++; //VC1
91
92 else if ((code & 0xf0) == VIDEO_ID && !pes) invalid++;
93 else if ((code & 0xe0) == AUDIO_ID && !pes) invalid++;
94 else if (code == PRIVATE_STREAM_1 && !pes) invalid++;
95 }
96 }
97
98 if (vid + audio > invalid + 1) /* invalid VDR files nd short PES streams */
99 score = AVPROBE_SCORE_EXTENSION / 2;
100
101 // av_log(NULL, AV_LOG_ERROR, "vid:%d aud:%d sys:%d pspack:%d invalid:%d size:%d \n",
102 // vid, audio, sys, pspack, invalid, p->buf_size);
103
104 if (sys > invalid && sys * 9 <= pspack * 10)
105 return (audio > 12 || vid > 3 || pspack > 2) ? AVPROBE_SCORE_EXTENSION + 2
106 : AVPROBE_SCORE_EXTENSION / 2 + (audio + vid + pspack > 1); // 1 more than mp3
107 if (pspack > invalid && (priv1 + vid + audio) * 10 >= pspack * 9)
108 return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2
109 : AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg
110 if ((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys &&
111 !pspack && p->buf_size > 2048 && vid + audio > invalid) /* PES stream */
112 return (audio > 12 || vid > 6 + 2 * invalid) ? AVPROBE_SCORE_EXTENSION + 2
113 : AVPROBE_SCORE_EXTENSION / 2;
114
115 // 02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1
116 // mp3_misidentified_2.mp3 has sys:0 priv1:0 pspack:0 vid:0 audio:6
117 // Have\ Yourself\ a\ Merry\ Little\ Christmas.mp3 0 0 0 5 0 1 len:21618
118 return score;
119 }
120
121 typedef struct MpegDemuxContext {
122 int32_t header_state;
123 unsigned char psm_es_type[256];
124 int sofdec;
125 int dvd;
126 int imkh_cctv;
127 int raw_ac3;
128 } MpegDemuxContext;
129
mpegps_read_header(AVFormatContext *s)130 static int mpegps_read_header(AVFormatContext *s)
131 {
132 MpegDemuxContext *m = s->priv_data;
133 char buffer[7] = { 0 };
134 int64_t last_pos = avio_tell(s->pb);
135
136 m->header_state = 0xff;
137 s->ctx_flags |= AVFMTCTX_NOHEADER;
138
139 avio_get_str(s->pb, 6, buffer, sizeof(buffer));
140 if (!memcmp("IMKH", buffer, 4)) {
141 m->imkh_cctv = 1;
142 } else if (!memcmp("Sofdec", buffer, 6)) {
143 m->sofdec = 1;
144 } else
145 avio_seek(s->pb, last_pos, SEEK_SET);
146
147 /* no need to do more */
148 return 0;
149 }
150
get_pts(AVIOContext *pb, int c)151 static int64_t get_pts(AVIOContext *pb, int c)
152 {
153 uint8_t buf[5];
154 int ret;
155
156 buf[0] = c < 0 ? avio_r8(pb) : c;
157 ret = avio_read(pb, buf + 1, 4);
158 if (ret < 4)
159 return AV_NOPTS_VALUE;
160
161 return ff_parse_pes_pts(buf);
162 }
163
find_next_start_code(AVIOContext *pb, int *size_ptr, int32_t *header_state)164 static int find_next_start_code(AVIOContext *pb, int *size_ptr,
165 int32_t *header_state)
166 {
167 unsigned int state, v;
168 int val, n;
169
170 state = *header_state;
171 n = *size_ptr;
172 while (n > 0) {
173 if (avio_feof(pb))
174 break;
175 v = avio_r8(pb);
176 n--;
177 if (state == 0x000001) {
178 state = ((state << 8) | v) & 0xffffff;
179 val = state;
180 goto found;
181 }
182 state = ((state << 8) | v) & 0xffffff;
183 }
184 val = -1;
185
186 found:
187 *header_state = state;
188 *size_ptr = n;
189 return val;
190 }
191
192 /**
193 * Extract stream types from a program stream map
194 * According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35
195 *
196 * @return number of bytes occupied by PSM in the bitstream
197 */
mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)198 static long mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)
199 {
200 int psm_length, ps_info_length, es_map_length;
201
202 psm_length = avio_rb16(pb);
203 avio_r8(pb);
204 avio_r8(pb);
205 ps_info_length = avio_rb16(pb);
206
207 /* skip program_stream_info */
208 avio_skip(pb, ps_info_length);
209 /*es_map_length = */avio_rb16(pb);
210 /* Ignore es_map_length, trust psm_length */
211 es_map_length = psm_length - ps_info_length - 10;
212
213 /* at least one es available? */
214 while (es_map_length >= 4) {
215 unsigned char type = avio_r8(pb);
216 unsigned char es_id = avio_r8(pb);
217 uint16_t es_info_length = avio_rb16(pb);
218
219 /* remember mapping from stream id to stream type */
220 m->psm_es_type[es_id] = type;
221 /* skip program_stream_info */
222 avio_skip(pb, es_info_length);
223 es_map_length -= 4 + es_info_length;
224 }
225 avio_rb32(pb); /* crc32 */
226 return 2 + psm_length;
227 }
228
229 /* read the next PES header. Return its position in ppos
230 * (if not NULL), and its start code, pts and dts.
231 */
mpegps_read_pes_header(AVFormatContext *s, int64_t *ppos, int *pstart_code, int64_t *ppts, int64_t *pdts)232 static int mpegps_read_pes_header(AVFormatContext *s,
233 int64_t *ppos, int *pstart_code,
234 int64_t *ppts, int64_t *pdts)
235 {
236 MpegDemuxContext *m = s->priv_data;
237 int len, size, startcode, c, flags, header_len;
238 int pes_ext, ext2_len, id_ext, skip;
239 int64_t pts, dts;
240 int64_t last_sync = avio_tell(s->pb);
241
242 error_redo:
243 avio_seek(s->pb, last_sync, SEEK_SET);
244 redo:
245 /* next start code (should be immediately after) */
246 m->header_state = 0xff;
247 size = MAX_SYNC_SIZE;
248 startcode = find_next_start_code(s->pb, &size, &m->header_state);
249 last_sync = avio_tell(s->pb);
250 if (startcode < 0) {
251 if (avio_feof(s->pb))
252 return AVERROR_EOF;
253 // FIXME we should remember header_state
254 return FFERROR_REDO;
255 }
256
257 if (startcode == PACK_START_CODE)
258 goto redo;
259 if (startcode == SYSTEM_HEADER_START_CODE)
260 goto redo;
261 if (startcode == PADDING_STREAM) {
262 avio_skip(s->pb, avio_rb16(s->pb));
263 goto redo;
264 }
265 if (startcode == PRIVATE_STREAM_2) {
266 if (!m->sofdec) {
267 /* Need to detect whether this from a DVD or a 'Sofdec' stream */
268 int len = avio_rb16(s->pb);
269 int bytesread = 0;
270 uint8_t *ps2buf = av_malloc(len);
271
272 if (ps2buf) {
273 bytesread = avio_read(s->pb, ps2buf, len);
274
275 if (bytesread != len) {
276 avio_skip(s->pb, len - bytesread);
277 } else {
278 uint8_t *p = 0;
279 if (len >= 6)
280 p = memchr(ps2buf, 'S', len - 5);
281
282 if (p)
283 m->sofdec = !memcmp(p+1, "ofdec", 5);
284
285 m->sofdec -= !m->sofdec;
286
287 if (m->sofdec < 0) {
288 if (len == 980 && ps2buf[0] == 0) {
289 /* PCI structure? */
290 uint32_t startpts = AV_RB32(ps2buf + 0x0d);
291 uint32_t endpts = AV_RB32(ps2buf + 0x11);
292 uint8_t hours = ((ps2buf[0x19] >> 4) * 10) + (ps2buf[0x19] & 0x0f);
293 uint8_t mins = ((ps2buf[0x1a] >> 4) * 10) + (ps2buf[0x1a] & 0x0f);
294 uint8_t secs = ((ps2buf[0x1b] >> 4) * 10) + (ps2buf[0x1b] & 0x0f);
295
296 m->dvd = (hours <= 23 &&
297 mins <= 59 &&
298 secs <= 59 &&
299 (ps2buf[0x19] & 0x0f) < 10 &&
300 (ps2buf[0x1a] & 0x0f) < 10 &&
301 (ps2buf[0x1b] & 0x0f) < 10 &&
302 endpts >= startpts);
303 } else if (len == 1018 && ps2buf[0] == 1) {
304 /* DSI structure? */
305 uint8_t hours = ((ps2buf[0x1d] >> 4) * 10) + (ps2buf[0x1d] & 0x0f);
306 uint8_t mins = ((ps2buf[0x1e] >> 4) * 10) + (ps2buf[0x1e] & 0x0f);
307 uint8_t secs = ((ps2buf[0x1f] >> 4) * 10) + (ps2buf[0x1f] & 0x0f);
308
309 m->dvd = (hours <= 23 &&
310 mins <= 59 &&
311 secs <= 59 &&
312 (ps2buf[0x1d] & 0x0f) < 10 &&
313 (ps2buf[0x1e] & 0x0f) < 10 &&
314 (ps2buf[0x1f] & 0x0f) < 10);
315 }
316 }
317 }
318
319 av_free(ps2buf);
320
321 /* If this isn't a DVD packet or no memory
322 * could be allocated, just ignore it.
323 * If we did, move back to the start of the
324 * packet (plus 'length' field) */
325 if (!m->dvd || avio_skip(s->pb, -(len + 2)) < 0) {
326 /* Skip back failed.
327 * This packet will be lost but that can't be helped
328 * if we can't skip back
329 */
330 goto redo;
331 }
332 } else {
333 /* No memory */
334 avio_skip(s->pb, len);
335 goto redo;
336 }
337 } else if (!m->dvd) {
338 int len = avio_rb16(s->pb);
339 avio_skip(s->pb, len);
340 goto redo;
341 }
342 }
343 if (startcode == PROGRAM_STREAM_MAP) {
344 mpegps_psm_parse(m, s->pb);
345 goto redo;
346 }
347
348 /* find matching stream */
349 if (!((startcode >= 0x1c0 && startcode <= 0x1df) ||
350 (startcode >= 0x1e0 && startcode <= 0x1ef) ||
351 (startcode == 0x1bd) ||
352 (startcode == PRIVATE_STREAM_2) ||
353 (startcode == 0x1fd)))
354 goto redo;
355 if (ppos) {
356 *ppos = avio_tell(s->pb) - 4;
357 }
358 len = avio_rb16(s->pb);
359 pts =
360 dts = AV_NOPTS_VALUE;
361 if (startcode != PRIVATE_STREAM_2)
362 {
363 /* stuffing */
364 for (;;) {
365 if (len < 1)
366 goto error_redo;
367 c = avio_r8(s->pb);
368 len--;
369 /* XXX: for MPEG-1, should test only bit 7 */
370 if (c != 0xff)
371 break;
372 }
373 if ((c & 0xc0) == 0x40) {
374 /* buffer scale & size */
375 avio_r8(s->pb);
376 c = avio_r8(s->pb);
377 len -= 2;
378 }
379 if ((c & 0xe0) == 0x20) {
380 dts =
381 pts = get_pts(s->pb, c);
382 len -= 4;
383 if (c & 0x10) {
384 dts = get_pts(s->pb, -1);
385 len -= 5;
386 }
387 } else if ((c & 0xc0) == 0x80) {
388 /* mpeg 2 PES */
389 flags = avio_r8(s->pb);
390 header_len = avio_r8(s->pb);
391 len -= 2;
392 if (header_len > len)
393 goto error_redo;
394 len -= header_len;
395 if (flags & 0x80) {
396 dts = pts = get_pts(s->pb, -1);
397 header_len -= 5;
398 if (flags & 0x40) {
399 dts = get_pts(s->pb, -1);
400 header_len -= 5;
401 }
402 }
403 if (flags & 0x3f && header_len == 0) {
404 flags &= 0xC0;
405 av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n");
406 }
407 if (flags & 0x01) { /* PES extension */
408 pes_ext = avio_r8(s->pb);
409 header_len--;
410 /* Skip PES private data, program packet sequence counter
411 * and P-STD buffer */
412 skip = (pes_ext >> 4) & 0xb;
413 skip += skip & 0x9;
414 if (pes_ext & 0x40 || skip > header_len) {
415 av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext);
416 pes_ext = skip = 0;
417 }
418 avio_skip(s->pb, skip);
419 header_len -= skip;
420
421 if (pes_ext & 0x01) { /* PES extension 2 */
422 ext2_len = avio_r8(s->pb);
423 header_len--;
424 if ((ext2_len & 0x7f) > 0) {
425 id_ext = avio_r8(s->pb);
426 if ((id_ext & 0x80) == 0)
427 startcode = ((startcode & 0xff) << 8) | id_ext;
428 header_len--;
429 }
430 }
431 }
432 if (header_len < 0)
433 goto error_redo;
434 avio_skip(s->pb, header_len);
435 } else if (c != 0xf)
436 goto redo;
437 }
438
439 if (startcode == PRIVATE_STREAM_1) {
440 int ret = ffio_ensure_seekback(s->pb, 2);
441
442 if (ret < 0)
443 return ret;
444
445 startcode = avio_r8(s->pb);
446 m->raw_ac3 = 0;
447 if (startcode == 0x0b) {
448 if (avio_r8(s->pb) == 0x77) {
449 startcode = 0x80;
450 m->raw_ac3 = 1;
451 avio_skip(s->pb, -2);
452 } else {
453 avio_skip(s->pb, -1);
454 }
455 } else {
456 len--;
457 }
458 }
459 if (len < 0)
460 goto error_redo;
461 if (dts != AV_NOPTS_VALUE && ppos) {
462 int i;
463 for (i = 0; i < s->nb_streams; i++) {
464 if (startcode == s->streams[i]->id &&
465 (s->pb->seekable & AVIO_SEEKABLE_NORMAL) /* index useless on streams anyway */) {
466 ff_reduce_index(s, i);
467 av_add_index_entry(s->streams[i], *ppos, dts, 0, 0,
468 AVINDEX_KEYFRAME /* FIXME keyframe? */);
469 }
470 }
471 }
472
473 *pstart_code = startcode;
474 *ppts = pts;
475 *pdts = dts;
476 return len;
477 }
478
mpegps_read_packet(AVFormatContext *s, AVPacket *pkt)479 static int mpegps_read_packet(AVFormatContext *s,
480 AVPacket *pkt)
481 {
482 MpegDemuxContext *m = s->priv_data;
483 AVStream *st;
484 FFStream *sti;
485 int len, startcode, i, es_type, ret;
486 int pcm_dvd = 0;
487 int request_probe= 0;
488 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
489 enum AVMediaType type;
490 int64_t pts, dts, dummy_pos; // dummy_pos is needed for the index building to work
491
492 redo:
493 len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts);
494 if (len < 0)
495 return len;
496
497 if (startcode >= 0x80 && startcode <= 0xcf) {
498 if (len < 4)
499 goto skip;
500
501 if (!m->raw_ac3) {
502 /* audio: skip header */
503 avio_skip(s->pb, 3);
504 len -= 3;
505 if (startcode >= 0xb0 && startcode <= 0xbf) {
506 /* MLP/TrueHD audio has a 4-byte header */
507 avio_r8(s->pb);
508 len--;
509 } else if (startcode >= 0xa0 && startcode <= 0xaf) {
510 ret = ffio_ensure_seekback(s->pb, 3);
511 if (ret < 0)
512 return ret;
513 pcm_dvd = (avio_rb24(s->pb) & 0xFF) == 0x80;
514 avio_skip(s->pb, -3);
515 }
516 }
517 }
518
519 /* now find stream */
520 for (i = 0; i < s->nb_streams; i++) {
521 st = s->streams[i];
522 if (st->id == startcode)
523 goto found;
524 }
525
526 es_type = m->psm_es_type[startcode & 0xff];
527 if (es_type == STREAM_TYPE_VIDEO_MPEG1) {
528 codec_id = AV_CODEC_ID_MPEG2VIDEO;
529 type = AVMEDIA_TYPE_VIDEO;
530 } else if (es_type == STREAM_TYPE_VIDEO_MPEG2) {
531 codec_id = AV_CODEC_ID_MPEG2VIDEO;
532 type = AVMEDIA_TYPE_VIDEO;
533 } else if (es_type == STREAM_TYPE_AUDIO_MPEG1 ||
534 es_type == STREAM_TYPE_AUDIO_MPEG2) {
535 codec_id = AV_CODEC_ID_MP3;
536 type = AVMEDIA_TYPE_AUDIO;
537 } else if (es_type == STREAM_TYPE_AUDIO_AAC) {
538 codec_id = AV_CODEC_ID_AAC;
539 type = AVMEDIA_TYPE_AUDIO;
540 } else if (es_type == STREAM_TYPE_VIDEO_MPEG4) {
541 codec_id = AV_CODEC_ID_MPEG4;
542 type = AVMEDIA_TYPE_VIDEO;
543 } else if (es_type == STREAM_TYPE_VIDEO_H264) {
544 codec_id = AV_CODEC_ID_H264;
545 type = AVMEDIA_TYPE_VIDEO;
546 } else if (es_type == STREAM_TYPE_VIDEO_HEVC) {
547 codec_id = AV_CODEC_ID_HEVC;
548 type = AVMEDIA_TYPE_VIDEO;
549 } else if (es_type == STREAM_TYPE_AUDIO_AC3) {
550 codec_id = AV_CODEC_ID_AC3;
551 type = AVMEDIA_TYPE_AUDIO;
552 } else if (m->imkh_cctv && es_type == 0x91) {
553 codec_id = AV_CODEC_ID_PCM_MULAW;
554 type = AVMEDIA_TYPE_AUDIO;
555 } else if (startcode >= 0x1e0 && startcode <= 0x1ef) {
556 static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };
557 unsigned char buf[8];
558
559 avio_read(s->pb, buf, 8);
560 avio_seek(s->pb, -8, SEEK_CUR);
561 if (!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1))
562 codec_id = AV_CODEC_ID_CAVS;
563 else
564 request_probe= 1;
565 type = AVMEDIA_TYPE_VIDEO;
566 } else if (startcode == PRIVATE_STREAM_2) {
567 type = AVMEDIA_TYPE_DATA;
568 codec_id = AV_CODEC_ID_DVD_NAV;
569 } else if (startcode >= 0x1c0 && startcode <= 0x1df) {
570 type = AVMEDIA_TYPE_AUDIO;
571 if (m->sofdec > 0) {
572 codec_id = AV_CODEC_ID_ADPCM_ADX;
573 // Auto-detect AC-3
574 request_probe = 50;
575 } else if (m->imkh_cctv && startcode == 0x1c0 && len > 80) {
576 codec_id = AV_CODEC_ID_PCM_ALAW;
577 request_probe = 50;
578 } else {
579 codec_id = AV_CODEC_ID_MP2;
580 if (m->imkh_cctv)
581 request_probe = 25;
582 }
583 } else if (startcode >= 0x80 && startcode <= 0x87) {
584 type = AVMEDIA_TYPE_AUDIO;
585 codec_id = AV_CODEC_ID_AC3;
586 } else if ((startcode >= 0x88 && startcode <= 0x8f) ||
587 (startcode >= 0x98 && startcode <= 0x9f)) {
588 /* 0x90 - 0x97 is reserved for SDDS in DVD specs */
589 type = AVMEDIA_TYPE_AUDIO;
590 codec_id = AV_CODEC_ID_DTS;
591 } else if (startcode >= 0xa0 && startcode <= 0xaf) {
592 type = AVMEDIA_TYPE_AUDIO;
593 if (!pcm_dvd) {
594 codec_id = AV_CODEC_ID_MLP;
595 } else {
596 codec_id = AV_CODEC_ID_PCM_DVD;
597 }
598 } else if (startcode >= 0xb0 && startcode <= 0xbf) {
599 type = AVMEDIA_TYPE_AUDIO;
600 codec_id = AV_CODEC_ID_TRUEHD;
601 } else if (startcode >= 0xc0 && startcode <= 0xcf) {
602 /* Used for both AC-3 and E-AC-3 in EVOB files */
603 type = AVMEDIA_TYPE_AUDIO;
604 codec_id = AV_CODEC_ID_AC3;
605 } else if (startcode >= 0x20 && startcode <= 0x3f) {
606 type = AVMEDIA_TYPE_SUBTITLE;
607 codec_id = AV_CODEC_ID_DVD_SUBTITLE;
608 } else if (startcode >= 0xfd55 && startcode <= 0xfd5f) {
609 type = AVMEDIA_TYPE_VIDEO;
610 codec_id = AV_CODEC_ID_VC1;
611 } else {
612 skip:
613 /* skip packet */
614 avio_skip(s->pb, len);
615 goto redo;
616 }
617 /* no stream found: add a new stream */
618 st = avformat_new_stream(s, NULL);
619 if (!st)
620 goto skip;
621 sti = ffstream(st);
622 st->id = startcode;
623 st->codecpar->codec_type = type;
624 st->codecpar->codec_id = codec_id;
625 if ( st->codecpar->codec_id == AV_CODEC_ID_PCM_MULAW
626 || st->codecpar->codec_id == AV_CODEC_ID_PCM_ALAW) {
627 st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
628 st->codecpar->sample_rate = 8000;
629 }
630 sti->request_probe = request_probe;
631 sti->need_parsing = AVSTREAM_PARSE_FULL;
632
633 found:
634 if (st->discard >= AVDISCARD_ALL)
635 goto skip;
636 if (startcode >= 0xa0 && startcode <= 0xaf) {
637 if (st->codecpar->codec_id == AV_CODEC_ID_MLP) {
638 if (len < 6)
639 goto skip;
640 avio_skip(s->pb, 6);
641 len -=6;
642 }
643 }
644 ret = av_get_packet(s->pb, pkt, len);
645
646 pkt->pts = pts;
647 pkt->dts = dts;
648 pkt->pos = dummy_pos;
649 pkt->stream_index = st->index;
650
651 if (s->debug & FF_FDEBUG_TS)
652 av_log(s, AV_LOG_DEBUG, "%d: pts=%0.3f dts=%0.3f size=%d\n",
653 pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0,
654 pkt->size);
655
656 return (ret < 0) ? ret : 0;
657 }
658
mpegps_read_dts(AVFormatContext *s, int stream_index, int64_t *ppos, int64_t pos_limit)659 static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index,
660 int64_t *ppos, int64_t pos_limit)
661 {
662 int len, startcode;
663 int64_t pos, pts, dts;
664
665 pos = *ppos;
666 if (avio_seek(s->pb, pos, SEEK_SET) < 0)
667 return AV_NOPTS_VALUE;
668
669 for (;;) {
670 len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts);
671 if (len < 0) {
672 if (s->debug & FF_FDEBUG_TS)
673 av_log(s, AV_LOG_DEBUG, "none (ret=%d)\n", len);
674 return AV_NOPTS_VALUE;
675 }
676 if (startcode == s->streams[stream_index]->id &&
677 dts != AV_NOPTS_VALUE) {
678 break;
679 }
680 avio_skip(s->pb, len);
681 }
682 if (s->debug & FF_FDEBUG_TS)
683 av_log(s, AV_LOG_DEBUG, "pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n",
684 pos, dts, dts / 90000.0);
685 *ppos = pos;
686 return dts;
687 }
688
689 const AVInputFormat ff_mpegps_demuxer = {
690 .name = "mpeg",
691 .long_name = NULL_IF_CONFIG_SMALL("MPEG-PS (MPEG-2 Program Stream)"),
692 .priv_data_size = sizeof(MpegDemuxContext),
693 .read_probe = mpegps_probe,
694 .read_header = mpegps_read_header,
695 .read_packet = mpegps_read_packet,
696 .read_timestamp = mpegps_read_dts,
697 .flags = AVFMT_SHOW_IDS | AVFMT_TS_DISCONT,
698 };
699
700 #if CONFIG_VOBSUB_DEMUXER
701
702 #include "subtitles.h"
703 #include "libavutil/avassert.h"
704 #include "libavutil/bprint.h"
705 #include "libavutil/opt.h"
706
707 #define REF_STRING "# VobSub index file,"
708 #define MAX_LINE_SIZE 2048
709
710 typedef struct VobSubDemuxContext {
711 const AVClass *class;
712 AVFormatContext *sub_ctx;
713 FFDemuxSubtitlesQueue q[32];
714 char *sub_name;
715 } VobSubDemuxContext;
716
vobsub_probe(const AVProbeData *p)717 static int vobsub_probe(const AVProbeData *p)
718 {
719 if (!strncmp(p->buf, REF_STRING, sizeof(REF_STRING) - 1))
720 return AVPROBE_SCORE_MAX;
721 return 0;
722 }
723
vobsub_read_close(AVFormatContext *s)724 static int vobsub_read_close(AVFormatContext *s)
725 {
726 VobSubDemuxContext *vobsub = s->priv_data;
727 int i;
728
729 for (i = 0; i < s->nb_streams; i++)
730 ff_subtitles_queue_clean(&vobsub->q[i]);
731 avformat_close_input(&vobsub->sub_ctx);
732 return 0;
733 }
734
vobsub_read_header(AVFormatContext *s)735 static int vobsub_read_header(AVFormatContext *s)
736 {
737 int i, ret = 0, header_parsed = 0, langidx = 0;
738 VobSubDemuxContext *vobsub = s->priv_data;
739 const AVInputFormat *iformat;
740 size_t fname_len;
741 AVBPrint header;
742 int64_t delay = 0;
743 AVStream *st = NULL;
744 int stream_id = -1;
745 char id[64] = {0};
746 char alt[MAX_LINE_SIZE] = {0};
747
748 if (!vobsub->sub_name) {
749 char *ext;
750 vobsub->sub_name = av_strdup(s->url);
751 if (!vobsub->sub_name) {
752 return AVERROR(ENOMEM);
753 }
754
755 fname_len = strlen(vobsub->sub_name);
756 ext = vobsub->sub_name - 3 + fname_len;
757 if (fname_len < 4 || *(ext - 1) != '.') {
758 av_log(s, AV_LOG_ERROR, "The input index filename is too short "
759 "to guess the associated .SUB file\n");
760 return AVERROR_INVALIDDATA;
761 }
762 memcpy(ext, !strncmp(ext, "IDX", 3) ? "SUB" : "sub", 3);
763 av_log(s, AV_LOG_VERBOSE, "IDX/SUB: %s -> %s\n", s->url, vobsub->sub_name);
764 }
765
766 if (!(iformat = av_find_input_format("mpeg"))) {
767 return AVERROR_DEMUXER_NOT_FOUND;
768 }
769
770 vobsub->sub_ctx = avformat_alloc_context();
771 if (!vobsub->sub_ctx) {
772 return AVERROR(ENOMEM);
773 }
774
775 if ((ret = ff_copy_whiteblacklists(vobsub->sub_ctx, s)) < 0)
776 return ret;
777
778 ret = avformat_open_input(&vobsub->sub_ctx, vobsub->sub_name, iformat, NULL);
779 if (ret < 0) {
780 av_log(s, AV_LOG_ERROR, "Unable to open %s as MPEG subtitles\n", vobsub->sub_name);
781 return ret;
782 }
783
784 av_bprint_init(&header, 0, INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE);
785
786 while (!avio_feof(s->pb)) {
787 char line[MAX_LINE_SIZE];
788 int len = ff_get_line(s->pb, line, sizeof(line));
789
790 if (!len)
791 break;
792
793 line[strcspn(line, "\r\n")] = 0;
794
795 if (!strncmp(line, "id:", 3)) {
796 if (sscanf(line, "id: %63[^,], index: %u", id, &stream_id) != 2) {
797 av_log(s, AV_LOG_WARNING, "Unable to parse index line '%s', "
798 "assuming 'id: und, index: 0'\n", line);
799 strcpy(id, "und");
800 stream_id = 0;
801 }
802
803 if (stream_id >= FF_ARRAY_ELEMS(vobsub->q)) {
804 av_log(s, AV_LOG_ERROR, "Maximum number of subtitles streams reached\n");
805 ret = AVERROR(EINVAL);
806 goto end;
807 }
808
809 header_parsed = 1;
810 alt[0] = '\0';
811 /* We do not create the stream immediately to avoid adding empty
812 * streams. See the following timestamp entry. */
813
814 av_log(s, AV_LOG_DEBUG, "IDX stream[%d] id=%s\n", stream_id, id);
815
816 } else if (!strncmp(line, "timestamp:", 10)) {
817 AVPacket *sub;
818 int hh, mm, ss, ms;
819 int64_t pos, timestamp;
820 const char *p = line + 10;
821
822 if (stream_id == -1) {
823 av_log(s, AV_LOG_ERROR, "Timestamp declared before any stream\n");
824 ret = AVERROR_INVALIDDATA;
825 goto end;
826 }
827
828 if (!st || st->id != stream_id) {
829 st = avformat_new_stream(s, NULL);
830 if (!st) {
831 ret = AVERROR(ENOMEM);
832 goto end;
833 }
834 st->id = stream_id;
835 st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
836 st->codecpar->codec_id = AV_CODEC_ID_DVD_SUBTITLE;
837 avpriv_set_pts_info(st, 64, 1, 1000);
838 av_dict_set(&st->metadata, "language", id, 0);
839 if (alt[0])
840 av_dict_set(&st->metadata, "title", alt, 0);
841 }
842
843 if (sscanf(p, "%02d:%02d:%02d:%03d, filepos: %"SCNx64,
844 &hh, &mm, &ss, &ms, &pos) != 5) {
845 av_log(s, AV_LOG_ERROR, "Unable to parse timestamp line '%s', "
846 "abort parsing\n", line);
847 ret = AVERROR_INVALIDDATA;
848 goto end;
849 }
850 timestamp = (hh*3600LL + mm*60LL + ss) * 1000LL + ms + delay;
851 timestamp = av_rescale_q(timestamp, av_make_q(1, 1000), st->time_base);
852
853 sub = ff_subtitles_queue_insert(&vobsub->q[s->nb_streams - 1], "", 0, 0);
854 if (!sub) {
855 ret = AVERROR(ENOMEM);
856 goto end;
857 }
858 sub->pos = pos;
859 sub->pts = timestamp;
860 sub->stream_index = s->nb_streams - 1;
861
862 } else if (!strncmp(line, "alt:", 4)) {
863 const char *p = line + 4;
864
865 while (*p == ' ')
866 p++;
867 av_log(s, AV_LOG_DEBUG, "IDX stream[%d] name=%s\n", stream_id, p);
868 av_strlcpy(alt, p, sizeof(alt));
869 header_parsed = 1;
870
871 } else if (!strncmp(line, "delay:", 6)) {
872 int sign = 1, hh = 0, mm = 0, ss = 0, ms = 0;
873 const char *p = line + 6;
874
875 while (*p == ' ')
876 p++;
877 if (*p == '-' || *p == '+') {
878 sign = *p == '-' ? -1 : 1;
879 p++;
880 }
881 sscanf(p, "%d:%d:%d:%d", &hh, &mm, &ss, &ms);
882 delay = ((hh*3600LL + mm*60LL + ss) * 1000LL + ms) * sign;
883
884 } else if (!strncmp(line, "langidx:", 8)) {
885 const char *p = line + 8;
886
887 if (sscanf(p, "%d", &langidx) != 1)
888 av_log(s, AV_LOG_ERROR, "Invalid langidx specified\n");
889
890 } else if (!header_parsed) {
891 if (line[0] && line[0] != '#')
892 av_bprintf(&header, "%s\n", line);
893 }
894 }
895
896 if (langidx < s->nb_streams)
897 s->streams[langidx]->disposition |= AV_DISPOSITION_DEFAULT;
898
899 for (i = 0; i < s->nb_streams; i++) {
900 vobsub->q[i].sort = SUB_SORT_POS_TS;
901 vobsub->q[i].keep_duplicates = 1;
902 ff_subtitles_queue_finalize(s, &vobsub->q[i]);
903 }
904
905 if (!av_bprint_is_complete(&header)) {
906 ret = AVERROR(ENOMEM);
907 goto end;
908 }
909 for (i = 0; i < s->nb_streams; i++) {
910 AVCodecParameters *par = s->streams[i]->codecpar;
911 ret = ff_alloc_extradata(par, header.len);
912 if (ret < 0) {
913 goto end;
914 }
915 memcpy(par->extradata, header.str, header.len);
916 }
917 end:
918 av_bprint_finalize(&header, NULL);
919 return ret;
920 }
921
vobsub_read_packet(AVFormatContext *s, AVPacket *pkt)922 static int vobsub_read_packet(AVFormatContext *s, AVPacket *pkt)
923 {
924 VobSubDemuxContext *vobsub = s->priv_data;
925 FFDemuxSubtitlesQueue *q;
926 AVIOContext *pb = vobsub->sub_ctx->pb;
927 int ret, psize, total_read = 0, i;
928
929 int64_t min_ts = INT64_MAX;
930 int sid = 0;
931 for (i = 0; i < s->nb_streams; i++) {
932 FFDemuxSubtitlesQueue *tmpq = &vobsub->q[i];
933 int64_t ts;
934 av_assert0(tmpq->nb_subs);
935
936 if (tmpq->current_sub_idx >= tmpq->nb_subs)
937 continue;
938
939 ts = tmpq->subs[tmpq->current_sub_idx]->pts;
940 if (ts < min_ts) {
941 min_ts = ts;
942 sid = i;
943 }
944 }
945 q = &vobsub->q[sid];
946 /* The returned packet will have size zero,
947 * so that it can be directly used with av_grow_packet. */
948 ret = ff_subtitles_queue_read_packet(q, pkt);
949 if (ret < 0)
950 return ret;
951
952 /* compute maximum packet size using the next packet position. This is
953 * useful when the len in the header is non-sense */
954 if (q->current_sub_idx < q->nb_subs) {
955 psize = q->subs[q->current_sub_idx]->pos - pkt->pos;
956 } else {
957 int64_t fsize = avio_size(pb);
958 psize = fsize < 0 ? 0xffff : fsize - pkt->pos;
959 }
960
961 avio_seek(pb, pkt->pos, SEEK_SET);
962
963 do {
964 int n, to_read, startcode;
965 int64_t pts, dts;
966 int64_t old_pos = avio_tell(pb), new_pos;
967 int pkt_size;
968
969 ret = mpegps_read_pes_header(vobsub->sub_ctx, NULL, &startcode, &pts, &dts);
970 if (ret < 0) {
971 if (pkt->size) // raise packet even if incomplete
972 break;
973 return ret;
974 }
975 to_read = ret & 0xffff;
976 new_pos = avio_tell(pb);
977 pkt_size = ret + (new_pos - old_pos);
978
979 /* this prevents reads above the current packet */
980 if (total_read + pkt_size > psize)
981 break;
982 total_read += pkt_size;
983
984 /* the current chunk doesn't match the stream index (unlikely) */
985 if ((startcode & 0x1f) != s->streams[pkt->stream_index]->id)
986 break;
987
988 ret = av_grow_packet(pkt, to_read);
989 if (ret < 0)
990 return ret;
991
992 n = avio_read(pb, pkt->data + (pkt->size - to_read), to_read);
993 if (n < to_read)
994 pkt->size -= to_read - n;
995 } while (total_read < psize);
996
997 return 0;
998 }
999
vobsub_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)1000 static int vobsub_read_seek(AVFormatContext *s, int stream_index,
1001 int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
1002 {
1003 VobSubDemuxContext *vobsub = s->priv_data;
1004
1005 /* Rescale requested timestamps based on the first stream (timebase is the
1006 * same for all subtitles stream within a .idx/.sub). Rescaling is done just
1007 * like in avformat_seek_file(). */
1008 if (stream_index == -1 && s->nb_streams != 1) {
1009 int i, ret = 0;
1010 AVRational time_base = s->streams[0]->time_base;
1011 ts = av_rescale_q(ts, AV_TIME_BASE_Q, time_base);
1012 min_ts = av_rescale_rnd(min_ts, time_base.den,
1013 time_base.num * (int64_t)AV_TIME_BASE,
1014 AV_ROUND_UP | AV_ROUND_PASS_MINMAX);
1015 max_ts = av_rescale_rnd(max_ts, time_base.den,
1016 time_base.num * (int64_t)AV_TIME_BASE,
1017 AV_ROUND_DOWN | AV_ROUND_PASS_MINMAX);
1018 for (i = 0; i < s->nb_streams; i++) {
1019 int r = ff_subtitles_queue_seek(&vobsub->q[i], s, stream_index,
1020 min_ts, ts, max_ts, flags);
1021 if (r < 0)
1022 ret = r;
1023 }
1024 return ret;
1025 }
1026
1027 if (stream_index == -1) // only 1 stream
1028 stream_index = 0;
1029 return ff_subtitles_queue_seek(&vobsub->q[stream_index], s, stream_index,
1030 min_ts, ts, max_ts, flags);
1031 }
1032
1033 static const AVOption options[] = {
1034 { "sub_name", "URI for .sub file", offsetof(VobSubDemuxContext, sub_name), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
1035 { NULL }
1036 };
1037
1038 static const AVClass vobsub_demuxer_class = {
1039 .class_name = "vobsub",
1040 .item_name = av_default_item_name,
1041 .option = options,
1042 .version = LIBAVUTIL_VERSION_INT,
1043 };
1044
1045 const AVInputFormat ff_vobsub_demuxer = {
1046 .name = "vobsub",
1047 .long_name = NULL_IF_CONFIG_SMALL("VobSub subtitle format"),
1048 .priv_data_size = sizeof(VobSubDemuxContext),
1049 .flags_internal = FF_FMT_INIT_CLEANUP,
1050 .read_probe = vobsub_probe,
1051 .read_header = vobsub_read_header,
1052 .read_packet = vobsub_read_packet,
1053 .read_seek2 = vobsub_read_seek,
1054 .read_close = vobsub_read_close,
1055 .flags = AVFMT_SHOW_IDS,
1056 .extensions = "idx",
1057 .priv_class = &vobsub_demuxer_class,
1058 };
1059 #endif
1060