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 "avformat.h"
23 #include "avio_internal.h"
24 #include "internal.h"
25 #include "mpeg.h"
26
27 /*********************************************/
28 /* demux code */
29
30 #define MAX_SYNC_SIZE 100000
31
check_pes(const uint8_t * p,const uint8_t * end)32 static int check_pes(const uint8_t *p, const uint8_t *end)
33 {
34 int pes1;
35 int pes2 = (p[3] & 0xC0) == 0x80 &&
36 (p[4] & 0xC0) != 0x40 &&
37 ((p[4] & 0xC0) == 0x00 ||
38 (p[4] & 0xC0) >> 2 == (p[6] & 0xF0));
39
40 for (p += 3; p < end && *p == 0xFF; p++) ;
41 if ((*p & 0xC0) == 0x40)
42 p += 2;
43
44 if ((*p & 0xF0) == 0x20)
45 pes1 = p[0] & p[2] & p[4] & 1;
46 else if ((*p & 0xF0) == 0x30)
47 pes1 = p[0] & p[2] & p[4] & p[5] & p[7] & p[9] & 1;
48 else
49 pes1 = *p == 0x0F;
50
51 return pes1 || pes2;
52 }
53
check_pack_header(const uint8_t * buf)54 static int check_pack_header(const uint8_t *buf)
55 {
56 return (buf[1] & 0xC0) == 0x40 || (buf[1] & 0xF0) == 0x20;
57 }
58
mpegps_probe(const AVProbeData * p)59 static int mpegps_probe(const AVProbeData *p)
60 {
61 uint32_t code = -1;
62 int i;
63 int sys = 0, pspack = 0, priv1 = 0, vid = 0;
64 int audio = 0, invalid = 0, score = 0;
65 int endpes = 0;
66
67 for (i = 0; i < p->buf_size; i++) {
68 code = (code << 8) + p->buf[i];
69 if ((code & 0xffffff00) == 0x100) {
70 int len = p->buf[i + 1] << 8 | p->buf[i + 2];
71 int pes = endpes <= i && check_pes(p->buf + i, p->buf + p->buf_size);
72 int pack = check_pack_header(p->buf + i);
73
74 if (code == SYSTEM_HEADER_START_CODE)
75 sys++;
76 else if (code == PACK_START_CODE && pack)
77 pspack++;
78 else if ((code & 0xf0) == VIDEO_ID && pes) {
79 endpes = i + len;
80 vid++;
81 }
82 // skip pes payload to avoid start code emulation for private
83 // and audio streams
84 else if ((code & 0xe0) == AUDIO_ID && pes) {audio++; i+=len;}
85 else if (code == PRIVATE_STREAM_1 && pes) {priv1++; i+=len;}
86 else if (code == 0x1fd && pes) vid++; //VC1
87
88 else if ((code & 0xf0) == VIDEO_ID && !pes) invalid++;
89 else if ((code & 0xe0) == AUDIO_ID && !pes) invalid++;
90 else if (code == PRIVATE_STREAM_1 && !pes) invalid++;
91 }
92 }
93
94 if (vid + audio > invalid + 1) /* invalid VDR files nd short PES streams */
95 score = AVPROBE_SCORE_EXTENSION / 2;
96
97 // av_log(NULL, AV_LOG_ERROR, "vid:%d aud:%d sys:%d pspack:%d invalid:%d size:%d \n",
98 // vid, audio, sys, pspack, invalid, p->buf_size);
99
100 if (sys > invalid && sys * 9 <= pspack * 10)
101 return (audio > 12 || vid > 3 || pspack > 2) ? AVPROBE_SCORE_EXTENSION + 2
102 : AVPROBE_SCORE_EXTENSION / 2 + (audio + vid + pspack > 1); // 1 more than mp3
103 if (pspack > invalid && (priv1 + vid + audio) * 10 >= pspack * 9)
104 return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2
105 : AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg
106 if ((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys &&
107 !pspack && p->buf_size > 2048 && vid + audio > invalid) /* PES stream */
108 return (audio > 12 || vid > 6 + 2 * invalid) ? AVPROBE_SCORE_EXTENSION + 2
109 : AVPROBE_SCORE_EXTENSION / 2;
110
111 // 02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1
112 // mp3_misidentified_2.mp3 has sys:0 priv1:0 pspack:0 vid:0 audio:6
113 // Have\ Yourself\ a\ Merry\ Little\ Christmas.mp3 0 0 0 5 0 1 len:21618
114 return score;
115 }
116
117 typedef struct MpegDemuxContext {
118 int32_t header_state;
119 unsigned char psm_es_type[256];
120 int sofdec;
121 int dvd;
122 int imkh_cctv;
123 int raw_ac3;
124 } MpegDemuxContext;
125
mpegps_read_header(AVFormatContext * s)126 static int mpegps_read_header(AVFormatContext *s)
127 {
128 MpegDemuxContext *m = s->priv_data;
129 char buffer[7] = { 0 };
130 int64_t last_pos = avio_tell(s->pb);
131
132 m->header_state = 0xff;
133 s->ctx_flags |= AVFMTCTX_NOHEADER;
134
135 avio_get_str(s->pb, 6, buffer, sizeof(buffer));
136 if (!memcmp("IMKH", buffer, 4)) {
137 m->imkh_cctv = 1;
138 } else if (!memcmp("Sofdec", buffer, 6)) {
139 m->sofdec = 1;
140 } else
141 avio_seek(s->pb, last_pos, SEEK_SET);
142
143 /* no need to do more */
144 return 0;
145 }
146
get_pts(AVIOContext * pb,int c)147 static int64_t get_pts(AVIOContext *pb, int c)
148 {
149 uint8_t buf[5];
150 int ret;
151
152 buf[0] = c < 0 ? avio_r8(pb) : c;
153 ret = avio_read(pb, buf + 1, 4);
154 if (ret < 4)
155 return AV_NOPTS_VALUE;
156
157 return ff_parse_pes_pts(buf);
158 }
159
find_next_start_code(AVIOContext * pb,int * size_ptr,int32_t * header_state)160 static int find_next_start_code(AVIOContext *pb, int *size_ptr,
161 int32_t *header_state)
162 {
163 unsigned int state, v;
164 int val, n;
165
166 state = *header_state;
167 n = *size_ptr;
168 while (n > 0) {
169 if (avio_feof(pb))
170 break;
171 v = avio_r8(pb);
172 n--;
173 if (state == 0x000001) {
174 state = ((state << 8) | v) & 0xffffff;
175 val = state;
176 goto found;
177 }
178 state = ((state << 8) | v) & 0xffffff;
179 }
180 val = -1;
181
182 found:
183 *header_state = state;
184 *size_ptr = n;
185 return val;
186 }
187
188 /**
189 * Extract stream types from a program stream map
190 * According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35
191 *
192 * @return number of bytes occupied by PSM in the bitstream
193 */
mpegps_psm_parse(MpegDemuxContext * m,AVIOContext * pb)194 static long mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)
195 {
196 int psm_length, ps_info_length, es_map_length;
197
198 psm_length = avio_rb16(pb);
199 avio_r8(pb);
200 avio_r8(pb);
201 ps_info_length = avio_rb16(pb);
202
203 /* skip program_stream_info */
204 avio_skip(pb, ps_info_length);
205 /*es_map_length = */avio_rb16(pb);
206 /* Ignore es_map_length, trust psm_length */
207 es_map_length = psm_length - ps_info_length - 10;
208
209 /* at least one es available? */
210 while (es_map_length >= 4) {
211 unsigned char type = avio_r8(pb);
212 unsigned char es_id = avio_r8(pb);
213 uint16_t es_info_length = avio_rb16(pb);
214
215 /* remember mapping from stream id to stream type */
216 m->psm_es_type[es_id] = type;
217 /* skip program_stream_info */
218 avio_skip(pb, es_info_length);
219 es_map_length -= 4 + es_info_length;
220 }
221 avio_rb32(pb); /* crc32 */
222 return 2 + psm_length;
223 }
224
225 /* read the next PES header. Return its position in ppos
226 * (if not NULL), and its start code, pts and dts.
227 */
mpegps_read_pes_header(AVFormatContext * s,int64_t * ppos,int * pstart_code,int64_t * ppts,int64_t * pdts)228 static int mpegps_read_pes_header(AVFormatContext *s,
229 int64_t *ppos, int *pstart_code,
230 int64_t *ppts, int64_t *pdts)
231 {
232 MpegDemuxContext *m = s->priv_data;
233 int len, size, startcode, c, flags, header_len;
234 int pes_ext, ext2_len, id_ext, skip;
235 int64_t pts, dts;
236 int64_t last_sync = avio_tell(s->pb);
237
238 error_redo:
239 avio_seek(s->pb, last_sync, SEEK_SET);
240 redo:
241 /* next start code (should be immediately after) */
242 m->header_state = 0xff;
243 size = MAX_SYNC_SIZE;
244 startcode = find_next_start_code(s->pb, &size, &m->header_state);
245 last_sync = avio_tell(s->pb);
246 if (startcode < 0) {
247 if (avio_feof(s->pb))
248 return AVERROR_EOF;
249 // FIXME we should remember header_state
250 return FFERROR_REDO;
251 }
252
253 if (startcode == PACK_START_CODE)
254 goto redo;
255 if (startcode == SYSTEM_HEADER_START_CODE)
256 goto redo;
257 if (startcode == PADDING_STREAM) {
258 avio_skip(s->pb, avio_rb16(s->pb));
259 goto redo;
260 }
261 if (startcode == PRIVATE_STREAM_2) {
262 if (!m->sofdec) {
263 /* Need to detect whether this from a DVD or a 'Sofdec' stream */
264 int len = avio_rb16(s->pb);
265 int bytesread = 0;
266 uint8_t *ps2buf = av_malloc(len);
267
268 if (ps2buf) {
269 bytesread = avio_read(s->pb, ps2buf, len);
270
271 if (bytesread != len) {
272 avio_skip(s->pb, len - bytesread);
273 } else {
274 uint8_t *p = 0;
275 if (len >= 6)
276 p = memchr(ps2buf, 'S', len - 5);
277
278 if (p)
279 m->sofdec = !memcmp(p+1, "ofdec", 5);
280
281 m->sofdec -= !m->sofdec;
282
283 if (m->sofdec < 0) {
284 if (len == 980 && ps2buf[0] == 0) {
285 /* PCI structure? */
286 uint32_t startpts = AV_RB32(ps2buf + 0x0d);
287 uint32_t endpts = AV_RB32(ps2buf + 0x11);
288 uint8_t hours = ((ps2buf[0x19] >> 4) * 10) + (ps2buf[0x19] & 0x0f);
289 uint8_t mins = ((ps2buf[0x1a] >> 4) * 10) + (ps2buf[0x1a] & 0x0f);
290 uint8_t secs = ((ps2buf[0x1b] >> 4) * 10) + (ps2buf[0x1b] & 0x0f);
291
292 m->dvd = (hours <= 23 &&
293 mins <= 59 &&
294 secs <= 59 &&
295 (ps2buf[0x19] & 0x0f) < 10 &&
296 (ps2buf[0x1a] & 0x0f) < 10 &&
297 (ps2buf[0x1b] & 0x0f) < 10 &&
298 endpts >= startpts);
299 } else if (len == 1018 && ps2buf[0] == 1) {
300 /* DSI structure? */
301 uint8_t hours = ((ps2buf[0x1d] >> 4) * 10) + (ps2buf[0x1d] & 0x0f);
302 uint8_t mins = ((ps2buf[0x1e] >> 4) * 10) + (ps2buf[0x1e] & 0x0f);
303 uint8_t secs = ((ps2buf[0x1f] >> 4) * 10) + (ps2buf[0x1f] & 0x0f);
304
305 m->dvd = (hours <= 23 &&
306 mins <= 59 &&
307 secs <= 59 &&
308 (ps2buf[0x1d] & 0x0f) < 10 &&
309 (ps2buf[0x1e] & 0x0f) < 10 &&
310 (ps2buf[0x1f] & 0x0f) < 10);
311 }
312 }
313 }
314
315 av_free(ps2buf);
316
317 /* If this isn't a DVD packet or no memory
318 * could be allocated, just ignore it.
319 * If we did, move back to the start of the
320 * packet (plus 'length' field) */
321 if (!m->dvd || avio_skip(s->pb, -(len + 2)) < 0) {
322 /* Skip back failed.
323 * This packet will be lost but that can't be helped
324 * if we can't skip back
325 */
326 goto redo;
327 }
328 } else {
329 /* No memory */
330 avio_skip(s->pb, len);
331 goto redo;
332 }
333 } else if (!m->dvd) {
334 int len = avio_rb16(s->pb);
335 avio_skip(s->pb, len);
336 goto redo;
337 }
338 }
339 if (startcode == PROGRAM_STREAM_MAP) {
340 mpegps_psm_parse(m, s->pb);
341 goto redo;
342 }
343
344 /* find matching stream */
345 if (!((startcode >= 0x1c0 && startcode <= 0x1df) ||
346 (startcode >= 0x1e0 && startcode <= 0x1ef) ||
347 (startcode == 0x1bd) ||
348 (startcode == PRIVATE_STREAM_2) ||
349 (startcode == 0x1fd)))
350 goto redo;
351 if (ppos) {
352 *ppos = avio_tell(s->pb) - 4;
353 }
354 len = avio_rb16(s->pb);
355 pts =
356 dts = AV_NOPTS_VALUE;
357 if (startcode != PRIVATE_STREAM_2)
358 {
359 /* stuffing */
360 for (;;) {
361 if (len < 1)
362 goto error_redo;
363 c = avio_r8(s->pb);
364 len--;
365 /* XXX: for MPEG-1, should test only bit 7 */
366 if (c != 0xff)
367 break;
368 }
369 if ((c & 0xc0) == 0x40) {
370 /* buffer scale & size */
371 avio_r8(s->pb);
372 c = avio_r8(s->pb);
373 len -= 2;
374 }
375 if ((c & 0xe0) == 0x20) {
376 dts =
377 pts = get_pts(s->pb, c);
378 len -= 4;
379 if (c & 0x10) {
380 dts = get_pts(s->pb, -1);
381 len -= 5;
382 }
383 } else if ((c & 0xc0) == 0x80) {
384 /* mpeg 2 PES */
385 flags = avio_r8(s->pb);
386 header_len = avio_r8(s->pb);
387 len -= 2;
388 if (header_len > len)
389 goto error_redo;
390 len -= header_len;
391 if (flags & 0x80) {
392 dts = pts = get_pts(s->pb, -1);
393 header_len -= 5;
394 if (flags & 0x40) {
395 dts = get_pts(s->pb, -1);
396 header_len -= 5;
397 }
398 }
399 if (flags & 0x3f && header_len == 0) {
400 flags &= 0xC0;
401 av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n");
402 }
403 if (flags & 0x01) { /* PES extension */
404 pes_ext = avio_r8(s->pb);
405 header_len--;
406 /* Skip PES private data, program packet sequence counter
407 * and P-STD buffer */
408 skip = (pes_ext >> 4) & 0xb;
409 skip += skip & 0x9;
410 if (pes_ext & 0x40 || skip > header_len) {
411 av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext);
412 pes_ext = skip = 0;
413 }
414 avio_skip(s->pb, skip);
415 header_len -= skip;
416
417 if (pes_ext & 0x01) { /* PES extension 2 */
418 ext2_len = avio_r8(s->pb);
419 header_len--;
420 if ((ext2_len & 0x7f) > 0) {
421 id_ext = avio_r8(s->pb);
422 if ((id_ext & 0x80) == 0)
423 startcode = ((startcode & 0xff) << 8) | id_ext;
424 header_len--;
425 }
426 }
427 }
428 if (header_len < 0)
429 goto error_redo;
430 avio_skip(s->pb, header_len);
431 } else if (c != 0xf)
432 goto redo;
433 }
434
435 if (startcode == PRIVATE_STREAM_1) {
436 int ret = ffio_ensure_seekback(s->pb, 2);
437
438 if (ret < 0)
439 return ret;
440
441 startcode = avio_r8(s->pb);
442 m->raw_ac3 = 0;
443 if (startcode == 0x0b) {
444 if (avio_r8(s->pb) == 0x77) {
445 startcode = 0x80;
446 m->raw_ac3 = 1;
447 avio_skip(s->pb, -2);
448 } else {
449 avio_skip(s->pb, -1);
450 }
451 } else {
452 len--;
453 }
454 }
455 if (len < 0)
456 goto error_redo;
457 if (dts != AV_NOPTS_VALUE && ppos) {
458 int i;
459 for (i = 0; i < s->nb_streams; i++) {
460 if (startcode == s->streams[i]->id &&
461 (s->pb->seekable & AVIO_SEEKABLE_NORMAL) /* index useless on streams anyway */) {
462 ff_reduce_index(s, i);
463 av_add_index_entry(s->streams[i], *ppos, dts, 0, 0,
464 AVINDEX_KEYFRAME /* FIXME keyframe? */);
465 }
466 }
467 }
468
469 *pstart_code = startcode;
470 *ppts = pts;
471 *pdts = dts;
472 return len;
473 }
474
mpegps_read_packet(AVFormatContext * s,AVPacket * pkt)475 static int mpegps_read_packet(AVFormatContext *s,
476 AVPacket *pkt)
477 {
478 MpegDemuxContext *m = s->priv_data;
479 AVStream *st;
480 int len, startcode, i, es_type, ret;
481 int pcm_dvd = 0;
482 int request_probe= 0;
483 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
484 enum AVMediaType type;
485 int64_t pts, dts, dummy_pos; // dummy_pos is needed for the index building to work
486
487 redo:
488 len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts);
489 if (len < 0)
490 return len;
491
492 if (startcode >= 0x80 && startcode <= 0xcf) {
493 if (len < 4)
494 goto skip;
495
496 if (!m->raw_ac3) {
497 /* audio: skip header */
498 avio_skip(s->pb, 3);
499 len -= 3;
500 if (startcode >= 0xb0 && startcode <= 0xbf) {
501 /* MLP/TrueHD audio has a 4-byte header */
502 avio_r8(s->pb);
503 len--;
504 } else if (startcode >= 0xa0 && startcode <= 0xaf) {
505 ret = ffio_ensure_seekback(s->pb, 3);
506 if (ret < 0)
507 return ret;
508 pcm_dvd = (avio_rb24(s->pb) & 0xFF) == 0x80;
509 avio_skip(s->pb, -3);
510 }
511 }
512 }
513
514 /* now find stream */
515 for (i = 0; i < s->nb_streams; i++) {
516 st = s->streams[i];
517 if (st->id == startcode)
518 goto found;
519 }
520
521 es_type = m->psm_es_type[startcode & 0xff];
522 if (es_type == STREAM_TYPE_VIDEO_MPEG1) {
523 codec_id = AV_CODEC_ID_MPEG2VIDEO;
524 type = AVMEDIA_TYPE_VIDEO;
525 } else if (es_type == STREAM_TYPE_VIDEO_MPEG2) {
526 codec_id = AV_CODEC_ID_MPEG2VIDEO;
527 type = AVMEDIA_TYPE_VIDEO;
528 } else if (es_type == STREAM_TYPE_AUDIO_MPEG1 ||
529 es_type == STREAM_TYPE_AUDIO_MPEG2) {
530 codec_id = AV_CODEC_ID_MP3;
531 type = AVMEDIA_TYPE_AUDIO;
532 } else if (es_type == STREAM_TYPE_AUDIO_AAC) {
533 codec_id = AV_CODEC_ID_AAC;
534 type = AVMEDIA_TYPE_AUDIO;
535 } else if (es_type == STREAM_TYPE_VIDEO_MPEG4) {
536 codec_id = AV_CODEC_ID_MPEG4;
537 type = AVMEDIA_TYPE_VIDEO;
538 } else if (es_type == STREAM_TYPE_VIDEO_H264) {
539 codec_id = AV_CODEC_ID_H264;
540 type = AVMEDIA_TYPE_VIDEO;
541 } else if (es_type == STREAM_TYPE_VIDEO_HEVC) {
542 codec_id = AV_CODEC_ID_HEVC;
543 type = AVMEDIA_TYPE_VIDEO;
544 } else if (es_type == STREAM_TYPE_AUDIO_AC3) {
545 codec_id = AV_CODEC_ID_AC3;
546 type = AVMEDIA_TYPE_AUDIO;
547 } else if (m->imkh_cctv && es_type == 0x91) {
548 codec_id = AV_CODEC_ID_PCM_MULAW;
549 type = AVMEDIA_TYPE_AUDIO;
550 } else if (startcode >= 0x1e0 && startcode <= 0x1ef) {
551 static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };
552 unsigned char buf[8];
553
554 avio_read(s->pb, buf, 8);
555 avio_seek(s->pb, -8, SEEK_CUR);
556 if (!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1))
557 codec_id = AV_CODEC_ID_CAVS;
558 else
559 request_probe= 1;
560 type = AVMEDIA_TYPE_VIDEO;
561 } else if (startcode == PRIVATE_STREAM_2) {
562 type = AVMEDIA_TYPE_DATA;
563 codec_id = AV_CODEC_ID_DVD_NAV;
564 } else if (startcode >= 0x1c0 && startcode <= 0x1df) {
565 type = AVMEDIA_TYPE_AUDIO;
566 if (m->sofdec > 0) {
567 codec_id = AV_CODEC_ID_ADPCM_ADX;
568 // Auto-detect AC-3
569 request_probe = 50;
570 } else if (m->imkh_cctv && startcode == 0x1c0 && len > 80) {
571 codec_id = AV_CODEC_ID_PCM_ALAW;
572 request_probe = 50;
573 } else {
574 codec_id = AV_CODEC_ID_MP2;
575 if (m->imkh_cctv)
576 request_probe = 25;
577 }
578 } else if (startcode >= 0x80 && startcode <= 0x87) {
579 type = AVMEDIA_TYPE_AUDIO;
580 codec_id = AV_CODEC_ID_AC3;
581 } else if ((startcode >= 0x88 && startcode <= 0x8f) ||
582 (startcode >= 0x98 && startcode <= 0x9f)) {
583 /* 0x90 - 0x97 is reserved for SDDS in DVD specs */
584 type = AVMEDIA_TYPE_AUDIO;
585 codec_id = AV_CODEC_ID_DTS;
586 } else if (startcode >= 0xa0 && startcode <= 0xaf) {
587 type = AVMEDIA_TYPE_AUDIO;
588 if (!pcm_dvd) {
589 codec_id = AV_CODEC_ID_MLP;
590 } else {
591 codec_id = AV_CODEC_ID_PCM_DVD;
592 }
593 } else if (startcode >= 0xb0 && startcode <= 0xbf) {
594 type = AVMEDIA_TYPE_AUDIO;
595 codec_id = AV_CODEC_ID_TRUEHD;
596 } else if (startcode >= 0xc0 && startcode <= 0xcf) {
597 /* Used for both AC-3 and E-AC-3 in EVOB files */
598 type = AVMEDIA_TYPE_AUDIO;
599 codec_id = AV_CODEC_ID_AC3;
600 } else if (startcode >= 0x20 && startcode <= 0x3f) {
601 type = AVMEDIA_TYPE_SUBTITLE;
602 codec_id = AV_CODEC_ID_DVD_SUBTITLE;
603 } else if (startcode >= 0xfd55 && startcode <= 0xfd5f) {
604 type = AVMEDIA_TYPE_VIDEO;
605 codec_id = AV_CODEC_ID_VC1;
606 } else {
607 skip:
608 /* skip packet */
609 avio_skip(s->pb, len);
610 goto redo;
611 }
612 /* no stream found: add a new stream */
613 st = avformat_new_stream(s, NULL);
614 if (!st)
615 goto skip;
616 st->id = startcode;
617 st->codecpar->codec_type = type;
618 st->codecpar->codec_id = codec_id;
619 if ( st->codecpar->codec_id == AV_CODEC_ID_PCM_MULAW
620 || st->codecpar->codec_id == AV_CODEC_ID_PCM_ALAW) {
621 st->codecpar->channels = 1;
622 st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
623 st->codecpar->sample_rate = 8000;
624 }
625 st->internal->request_probe = request_probe;
626 st->need_parsing = AVSTREAM_PARSE_FULL;
627
628 found:
629 if (st->discard >= AVDISCARD_ALL)
630 goto skip;
631 if (startcode >= 0xa0 && startcode <= 0xaf) {
632 if (st->codecpar->codec_id == AV_CODEC_ID_MLP) {
633 if (len < 6)
634 goto skip;
635 avio_skip(s->pb, 6);
636 len -=6;
637 }
638 }
639 ret = av_get_packet(s->pb, pkt, len);
640
641 pkt->pts = pts;
642 pkt->dts = dts;
643 pkt->pos = dummy_pos;
644 pkt->stream_index = st->index;
645
646 if (s->debug & FF_FDEBUG_TS)
647 av_log(s, AV_LOG_DEBUG, "%d: pts=%0.3f dts=%0.3f size=%d\n",
648 pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0,
649 pkt->size);
650
651 return (ret < 0) ? ret : 0;
652 }
653
mpegps_read_dts(AVFormatContext * s,int stream_index,int64_t * ppos,int64_t pos_limit)654 static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index,
655 int64_t *ppos, int64_t pos_limit)
656 {
657 int len, startcode;
658 int64_t pos, pts, dts;
659
660 pos = *ppos;
661 if (avio_seek(s->pb, pos, SEEK_SET) < 0)
662 return AV_NOPTS_VALUE;
663
664 for (;;) {
665 len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts);
666 if (len < 0) {
667 if (s->debug & FF_FDEBUG_TS)
668 av_log(s, AV_LOG_DEBUG, "none (ret=%d)\n", len);
669 return AV_NOPTS_VALUE;
670 }
671 if (startcode == s->streams[stream_index]->id &&
672 dts != AV_NOPTS_VALUE) {
673 break;
674 }
675 avio_skip(s->pb, len);
676 }
677 if (s->debug & FF_FDEBUG_TS)
678 av_log(s, AV_LOG_DEBUG, "pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n",
679 pos, dts, dts / 90000.0);
680 *ppos = pos;
681 return dts;
682 }
683
684 AVInputFormat ff_mpegps_demuxer = {
685 .name = "mpeg",
686 .long_name = NULL_IF_CONFIG_SMALL("MPEG-PS (MPEG-2 Program Stream)"),
687 .priv_data_size = sizeof(MpegDemuxContext),
688 .read_probe = mpegps_probe,
689 .read_header = mpegps_read_header,
690 .read_packet = mpegps_read_packet,
691 .read_timestamp = mpegps_read_dts,
692 .flags = AVFMT_SHOW_IDS | AVFMT_TS_DISCONT,
693 };
694
695 #if CONFIG_VOBSUB_DEMUXER
696
697 #include "subtitles.h"
698 #include "libavutil/avassert.h"
699 #include "libavutil/bprint.h"
700 #include "libavutil/opt.h"
701
702 #define REF_STRING "# VobSub index file,"
703 #define MAX_LINE_SIZE 2048
704
705 typedef struct VobSubDemuxContext {
706 const AVClass *class;
707 AVFormatContext *sub_ctx;
708 FFDemuxSubtitlesQueue q[32];
709 char *sub_name;
710 } VobSubDemuxContext;
711
vobsub_probe(const AVProbeData * p)712 static int vobsub_probe(const AVProbeData *p)
713 {
714 if (!strncmp(p->buf, REF_STRING, sizeof(REF_STRING) - 1))
715 return AVPROBE_SCORE_MAX;
716 return 0;
717 }
718
vobsub_read_close(AVFormatContext * s)719 static int vobsub_read_close(AVFormatContext *s)
720 {
721 VobSubDemuxContext *vobsub = s->priv_data;
722 int i;
723
724 for (i = 0; i < s->nb_streams; i++)
725 ff_subtitles_queue_clean(&vobsub->q[i]);
726 if (vobsub->sub_ctx)
727 avformat_close_input(&vobsub->sub_ctx);
728 return 0;
729 }
730
vobsub_read_header(AVFormatContext * s)731 static int vobsub_read_header(AVFormatContext *s)
732 {
733 int i, ret = 0, header_parsed = 0, langidx = 0;
734 VobSubDemuxContext *vobsub = s->priv_data;
735 size_t fname_len;
736 AVBPrint header;
737 int64_t delay = 0;
738 AVStream *st = NULL;
739 int stream_id = -1;
740 char id[64] = {0};
741 char alt[MAX_LINE_SIZE] = {0};
742 ff_const59 AVInputFormat *iformat;
743
744 if (!vobsub->sub_name) {
745 char *ext;
746 vobsub->sub_name = av_strdup(s->url);
747 if (!vobsub->sub_name) {
748 return AVERROR(ENOMEM);
749 }
750
751 fname_len = strlen(vobsub->sub_name);
752 ext = vobsub->sub_name - 3 + fname_len;
753 if (fname_len < 4 || *(ext - 1) != '.') {
754 av_log(s, AV_LOG_ERROR, "The input index filename is too short "
755 "to guess the associated .SUB file\n");
756 return AVERROR_INVALIDDATA;
757 }
758 memcpy(ext, !strncmp(ext, "IDX", 3) ? "SUB" : "sub", 3);
759 av_log(s, AV_LOG_VERBOSE, "IDX/SUB: %s -> %s\n", s->url, vobsub->sub_name);
760 }
761
762 if (!(iformat = av_find_input_format("mpeg"))) {
763 return AVERROR_DEMUXER_NOT_FOUND;
764 }
765
766 vobsub->sub_ctx = avformat_alloc_context();
767 if (!vobsub->sub_ctx) {
768 return AVERROR(ENOMEM);
769 }
770
771 av_bprint_init(&header, 0, INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE);
772
773 if ((ret = ff_copy_whiteblacklists(vobsub->sub_ctx, s)) < 0)
774 goto end;
775
776 ret = avformat_open_input(&vobsub->sub_ctx, vobsub->sub_name, iformat, NULL);
777 if (ret < 0) {
778 av_log(s, AV_LOG_ERROR, "Unable to open %s as MPEG subtitles\n", vobsub->sub_name);
779 goto end;
780 }
781
782 while (!avio_feof(s->pb)) {
783 char line[MAX_LINE_SIZE];
784 int len = ff_get_line(s->pb, line, sizeof(line));
785
786 if (!len)
787 break;
788
789 line[strcspn(line, "\r\n")] = 0;
790
791 if (!strncmp(line, "id:", 3)) {
792 if (sscanf(line, "id: %63[^,], index: %u", id, &stream_id) != 2) {
793 av_log(s, AV_LOG_WARNING, "Unable to parse index line '%s', "
794 "assuming 'id: und, index: 0'\n", line);
795 strcpy(id, "und");
796 stream_id = 0;
797 }
798
799 if (stream_id >= FF_ARRAY_ELEMS(vobsub->q)) {
800 av_log(s, AV_LOG_ERROR, "Maximum number of subtitles streams reached\n");
801 ret = AVERROR(EINVAL);
802 goto end;
803 }
804
805 header_parsed = 1;
806 alt[0] = '\0';
807 /* We do not create the stream immediately to avoid adding empty
808 * streams. See the following timestamp entry. */
809
810 av_log(s, AV_LOG_DEBUG, "IDX stream[%d] id=%s\n", stream_id, id);
811
812 } else if (!strncmp(line, "timestamp:", 10)) {
813 AVPacket *sub;
814 int hh, mm, ss, ms;
815 int64_t pos, timestamp;
816 const char *p = line + 10;
817
818 if (stream_id == -1) {
819 av_log(s, AV_LOG_ERROR, "Timestamp declared before any stream\n");
820 ret = AVERROR_INVALIDDATA;
821 goto end;
822 }
823
824 if (!st || st->id != stream_id) {
825 st = avformat_new_stream(s, NULL);
826 if (!st) {
827 ret = AVERROR(ENOMEM);
828 goto end;
829 }
830 st->id = stream_id;
831 st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
832 st->codecpar->codec_id = AV_CODEC_ID_DVD_SUBTITLE;
833 avpriv_set_pts_info(st, 64, 1, 1000);
834 av_dict_set(&st->metadata, "language", id, 0);
835 if (alt[0])
836 av_dict_set(&st->metadata, "title", alt, 0);
837 }
838
839 if (sscanf(p, "%02d:%02d:%02d:%03d, filepos: %"SCNx64,
840 &hh, &mm, &ss, &ms, &pos) != 5) {
841 av_log(s, AV_LOG_ERROR, "Unable to parse timestamp line '%s', "
842 "abort parsing\n", line);
843 ret = AVERROR_INVALIDDATA;
844 goto end;
845 }
846 timestamp = (hh*3600LL + mm*60LL + ss) * 1000LL + ms + delay;
847 timestamp = av_rescale_q(timestamp, av_make_q(1, 1000), st->time_base);
848
849 sub = ff_subtitles_queue_insert(&vobsub->q[s->nb_streams - 1], "", 0, 0);
850 if (!sub) {
851 ret = AVERROR(ENOMEM);
852 goto end;
853 }
854 sub->pos = pos;
855 sub->pts = timestamp;
856 sub->stream_index = s->nb_streams - 1;
857
858 } else if (!strncmp(line, "alt:", 4)) {
859 const char *p = line + 4;
860
861 while (*p == ' ')
862 p++;
863 av_log(s, AV_LOG_DEBUG, "IDX stream[%d] name=%s\n", stream_id, p);
864 av_strlcpy(alt, p, sizeof(alt));
865 header_parsed = 1;
866
867 } else if (!strncmp(line, "delay:", 6)) {
868 int sign = 1, hh = 0, mm = 0, ss = 0, ms = 0;
869 const char *p = line + 6;
870
871 while (*p == ' ')
872 p++;
873 if (*p == '-' || *p == '+') {
874 sign = *p == '-' ? -1 : 1;
875 p++;
876 }
877 sscanf(p, "%d:%d:%d:%d", &hh, &mm, &ss, &ms);
878 delay = ((hh*3600LL + mm*60LL + ss) * 1000LL + ms) * sign;
879
880 } else if (!strncmp(line, "langidx:", 8)) {
881 const char *p = line + 8;
882
883 if (sscanf(p, "%d", &langidx) != 1)
884 av_log(s, AV_LOG_ERROR, "Invalid langidx specified\n");
885
886 } else if (!header_parsed) {
887 if (line[0] && line[0] != '#')
888 av_bprintf(&header, "%s\n", line);
889 }
890 }
891
892 if (langidx < s->nb_streams)
893 s->streams[langidx]->disposition |= AV_DISPOSITION_DEFAULT;
894
895 for (i = 0; i < s->nb_streams; i++) {
896 vobsub->q[i].sort = SUB_SORT_POS_TS;
897 vobsub->q[i].keep_duplicates = 1;
898 ff_subtitles_queue_finalize(s, &vobsub->q[i]);
899 }
900
901 if (!av_bprint_is_complete(&header)) {
902 ret = AVERROR(ENOMEM);
903 goto end;
904 }
905 for (i = 0; i < s->nb_streams; i++) {
906 AVCodecParameters *par = s->streams[i]->codecpar;
907 ret = ff_alloc_extradata(par, header.len);
908 if (ret < 0) {
909 goto end;
910 }
911 memcpy(par->extradata, header.str, header.len);
912 }
913 end:
914 if (ret < 0)
915 vobsub_read_close(s);
916 av_bprint_finalize(&header, NULL);
917 return ret;
918 }
919
vobsub_read_packet(AVFormatContext * s,AVPacket * pkt)920 static int vobsub_read_packet(AVFormatContext *s, AVPacket *pkt)
921 {
922 VobSubDemuxContext *vobsub = s->priv_data;
923 FFDemuxSubtitlesQueue *q;
924 AVIOContext *pb = vobsub->sub_ctx->pb;
925 int ret, psize, total_read = 0, i;
926
927 int64_t min_ts = INT64_MAX;
928 int sid = 0;
929 for (i = 0; i < s->nb_streams; i++) {
930 FFDemuxSubtitlesQueue *tmpq = &vobsub->q[i];
931 int64_t ts;
932 av_assert0(tmpq->nb_subs);
933
934 if (tmpq->current_sub_idx >= tmpq->nb_subs)
935 continue;
936
937 ts = tmpq->subs[tmpq->current_sub_idx]->pts;
938 if (ts < min_ts) {
939 min_ts = ts;
940 sid = i;
941 }
942 }
943 q = &vobsub->q[sid];
944 /* The returned packet will have size zero,
945 * so that it can be directly used with av_grow_packet. */
946 ret = ff_subtitles_queue_read_packet(q, pkt);
947 if (ret < 0)
948 return ret;
949
950 /* compute maximum packet size using the next packet position. This is
951 * useful when the len in the header is non-sense */
952 if (q->current_sub_idx < q->nb_subs) {
953 psize = q->subs[q->current_sub_idx]->pos - pkt->pos;
954 } else {
955 int64_t fsize = avio_size(pb);
956 psize = fsize < 0 ? 0xffff : fsize - pkt->pos;
957 }
958
959 avio_seek(pb, pkt->pos, SEEK_SET);
960
961 do {
962 int n, to_read, startcode;
963 int64_t pts, dts;
964 int64_t old_pos = avio_tell(pb), new_pos;
965 int pkt_size;
966
967 ret = mpegps_read_pes_header(vobsub->sub_ctx, NULL, &startcode, &pts, &dts);
968 if (ret < 0) {
969 if (pkt->size) // raise packet even if incomplete
970 break;
971 return ret;
972 }
973 to_read = ret & 0xffff;
974 new_pos = avio_tell(pb);
975 pkt_size = ret + (new_pos - old_pos);
976
977 /* this prevents reads above the current packet */
978 if (total_read + pkt_size > psize)
979 break;
980 total_read += pkt_size;
981
982 /* the current chunk doesn't match the stream index (unlikely) */
983 if ((startcode & 0x1f) != s->streams[pkt->stream_index]->id)
984 break;
985
986 ret = av_grow_packet(pkt, to_read);
987 if (ret < 0)
988 return ret;
989
990 n = avio_read(pb, pkt->data + (pkt->size - to_read), to_read);
991 if (n < to_read)
992 pkt->size -= to_read - n;
993 } while (total_read < psize);
994
995 return 0;
996 }
997
vobsub_read_seek(AVFormatContext * s,int stream_index,int64_t min_ts,int64_t ts,int64_t max_ts,int flags)998 static int vobsub_read_seek(AVFormatContext *s, int stream_index,
999 int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
1000 {
1001 VobSubDemuxContext *vobsub = s->priv_data;
1002
1003 /* Rescale requested timestamps based on the first stream (timebase is the
1004 * same for all subtitles stream within a .idx/.sub). Rescaling is done just
1005 * like in avformat_seek_file(). */
1006 if (stream_index == -1 && s->nb_streams != 1) {
1007 int i, ret = 0;
1008 AVRational time_base = s->streams[0]->time_base;
1009 ts = av_rescale_q(ts, AV_TIME_BASE_Q, time_base);
1010 min_ts = av_rescale_rnd(min_ts, time_base.den,
1011 time_base.num * (int64_t)AV_TIME_BASE,
1012 AV_ROUND_UP | AV_ROUND_PASS_MINMAX);
1013 max_ts = av_rescale_rnd(max_ts, time_base.den,
1014 time_base.num * (int64_t)AV_TIME_BASE,
1015 AV_ROUND_DOWN | AV_ROUND_PASS_MINMAX);
1016 for (i = 0; i < s->nb_streams; i++) {
1017 int r = ff_subtitles_queue_seek(&vobsub->q[i], s, stream_index,
1018 min_ts, ts, max_ts, flags);
1019 if (r < 0)
1020 ret = r;
1021 }
1022 return ret;
1023 }
1024
1025 if (stream_index == -1) // only 1 stream
1026 stream_index = 0;
1027 return ff_subtitles_queue_seek(&vobsub->q[stream_index], s, stream_index,
1028 min_ts, ts, max_ts, flags);
1029 }
1030
1031 static const AVOption options[] = {
1032 { "sub_name", "URI for .sub file", offsetof(VobSubDemuxContext, sub_name), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
1033 { NULL }
1034 };
1035
1036 static const AVClass vobsub_demuxer_class = {
1037 .class_name = "vobsub",
1038 .item_name = av_default_item_name,
1039 .option = options,
1040 .version = LIBAVUTIL_VERSION_INT,
1041 };
1042
1043 AVInputFormat ff_vobsub_demuxer = {
1044 .name = "vobsub",
1045 .long_name = NULL_IF_CONFIG_SMALL("VobSub subtitle format"),
1046 .priv_data_size = sizeof(VobSubDemuxContext),
1047 .read_probe = vobsub_probe,
1048 .read_header = vobsub_read_header,
1049 .read_packet = vobsub_read_packet,
1050 .read_seek2 = vobsub_read_seek,
1051 .read_close = vobsub_read_close,
1052 .flags = AVFMT_SHOW_IDS,
1053 .extensions = "idx",
1054 .priv_class = &vobsub_demuxer_class,
1055 };
1056 #endif
1057