path: root/libavformat/mpeg.c (plain)
blob: 68a848a6f635127cd92e6dfc1c8a28327257141d

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 "internal.h"
24	#include "mpeg.h"
25
26	#if CONFIG_VOBSUB_DEMUXER
27	# include "subtitles.h"
28	# include "libavutil/bprint.h"
29	# include "libavutil/opt.h"
30	#endif
31
32	#include "libavutil/avassert.h"
33
34	/*********************************************/
35	/* demux code */
36
37	#define MAX_SYNC_SIZE 100000
38
39	static int check_pes(const uint8_t *p, const uint8_t *end)
40	{
41	int pes1;
42	int pes2 = (p[3] & 0xC0) == 0x80 &&
43	(p[4] & 0xC0) != 0x40 &&
44	((p[4] & 0xC0) == 0x00 ||
45	(p[4] & 0xC0) >> 2 == (p[6] & 0xF0));
46
47	for (p += 3; p < end && *p == 0xFF; p++) ;
48	if ((*p & 0xC0) == 0x40)
49	p += 2;
50
51	if ((*p & 0xF0) == 0x20)
52	pes1 = p[0] & p[2] & p[4] & 1;
53	else if ((*p & 0xF0) == 0x30)
54	pes1 = p[0] & p[2] & p[4] & p[5] & p[7] & p[9] & 1;
55	else
56	pes1 = *p == 0x0F;
57
58	return pes1 || pes2;
59	}
60
61	static int check_pack_header(const uint8_t *buf)
62	{
63	return (buf[1] & 0xC0) == 0x40 || (buf[1] & 0xF0) == 0x20;
64	}
65
66	static int mpegps_probe(AVProbeData *p)
67	{
68	uint32_t code = -1;
69	int i;
70	int sys = 0, pspack = 0, priv1 = 0, vid = 0;
71	int audio = 0, invalid = 0, score = 0;
72	int endpes = 0;
73
74	for (i = 0; i < p->buf_size; i++) {
75	code = (code << 8) + p->buf[i];
76	if ((code & 0xffffff00) == 0x100) {
77	int len = p->buf[i + 1] << 8 | p->buf[i + 2];
78	int pes = endpes <= i && check_pes(p->buf + i, p->buf + p->buf_size);
79	int pack = check_pack_header(p->buf + i);
80
81	if (code == SYSTEM_HEADER_START_CODE)
82	sys++;
83	else if (code == PACK_START_CODE && pack)
84	pspack++;
85	else if ((code & 0xf0) == VIDEO_ID && pes) {
86	endpes = i + len;
87	vid++;
88	}
89	// skip pes payload to avoid start code emulation for private
90	// and audio streams
91	else if ((code & 0xe0) == AUDIO_ID && pes) {audio++; i+=len;}
92	else if (code == PRIVATE_STREAM_1 && pes) {priv1++; i+=len;}
93	else if (code == 0x1fd && pes) vid++; //VC1
94
95	else if ((code & 0xf0) == VIDEO_ID && !pes) invalid++;
96	else if ((code & 0xe0) == AUDIO_ID && !pes) invalid++;
97	else if (code == PRIVATE_STREAM_1 && !pes) invalid++;
98	}
99	}
100
101	if (vid + audio > invalid + 1) /* invalid VDR files nd short PES streams */
102	score = AVPROBE_SCORE_EXTENSION / 2;
103
104	// av_log(NULL, AV_LOG_ERROR, "vid:%d aud:%d sys:%d pspack:%d invalid:%d size:%d \n",
105	// vid, audio, sys, pspack, invalid, p->buf_size);
106
107	if (sys > invalid && sys * 9 <= pspack * 10)
108	return (audio > 12 || vid > 3 || pspack > 2) ? AVPROBE_SCORE_EXTENSION + 2
109	: AVPROBE_SCORE_EXTENSION / 2 + 1; // 1 more than mp3
110	if (pspack > invalid && (priv1 + vid + audio) * 10 >= pspack * 9)
111	return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2
112	: AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg
113	if ((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys &&
114	!pspack && p->buf_size > 2048 && vid + audio > invalid) /* PES stream */
115	return (audio > 12 || vid > 6 + 2 * invalid) ? AVPROBE_SCORE_EXTENSION + 2
116	: AVPROBE_SCORE_EXTENSION / 2;
117
118	// 02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1
119	// mp3_misidentified_2.mp3 has sys:0 priv1:0 pspack:0 vid:0 audio:6
120	// Have\ Yourself\ a\ Merry\ Little\ Christmas.mp3 0 0 0 5 0 1 len:21618
121	return score;
122	}
123
124	typedef struct MpegDemuxContext {
125	AVClass *class;
126	int32_t header_state;
127	unsigned char psm_es_type[256];
128	int sofdec;
129	int dvd;
130	int imkh_cctv;
131	#if CONFIG_VOBSUB_DEMUXER
132	AVFormatContext *sub_ctx;
133	FFDemuxSubtitlesQueue q[32];
134	char *sub_name;
135	#endif
136	} MpegDemuxContext;
137
138	static int mpegps_read_header(AVFormatContext *s)
139	{
140	MpegDemuxContext *m = s->priv_data;
141	char buffer[7] = { 0 };
142	int64_t last_pos = avio_tell(s->pb);
143
144	m->header_state = 0xff;
145	s->ctx_flags |= AVFMTCTX_NOHEADER;
146
147	avio_get_str(s->pb, 6, buffer, sizeof(buffer));
148	if (!memcmp("IMKH", buffer, 4)) {
149	m->imkh_cctv = 1;
150	} else if (!memcmp("Sofdec", buffer, 6)) {
151	m->sofdec = 1;
152	} else
153	avio_seek(s->pb, last_pos, SEEK_SET);
154
155	/* no need to do more */
156	return 0;
157	}
158
159	static int64_t get_pts(AVIOContext *pb, int c)
160	{
161	uint8_t buf[5];
162
163	buf[0] = c < 0 ? avio_r8(pb) : c;
164	avio_read(pb, buf + 1, 4);
165
166	return ff_parse_pes_pts(buf);
167	}
168
169	static int find_next_start_code(AVIOContext *pb, int *size_ptr,
170	int32_t *header_state)
171	{
172	unsigned int state, v;
173	int val, n;
174
175	state = *header_state;
176	n = *size_ptr;
177	while (n > 0) {
178	if (avio_feof(pb))
179	break;
180	v = avio_r8(pb);
181	n--;
182	if (state == 0x000001) {
183	state = ((state << 8) | v) & 0xffffff;
184	val = state;
185	goto found;
186	}
187	state = ((state << 8) | v) & 0xffffff;
188	}
189	val = -1;
190
191	found:
192	*header_state = state;
193	*size_ptr = n;
194	return val;
195	}
196
197	/**
198	* Extract stream types from a program stream map
199	* According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35
200	*
201	* @return number of bytes occupied by PSM in the bitstream
202	*/
203	static long mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)
204	{
205	int psm_length, ps_info_length, es_map_length;
206
207	psm_length = avio_rb16(pb);
208	avio_r8(pb);
209	avio_r8(pb);
210	ps_info_length = avio_rb16(pb);
211
212	/* skip program_stream_info */
213	avio_skip(pb, ps_info_length);
214	/*es_map_length = */avio_rb16(pb);
215	/* Ignore es_map_length, trust psm_length */
216	es_map_length = psm_length - ps_info_length - 10;
217
218	/* at least one es available? */
219	while (es_map_length >= 4) {
220	unsigned char type = avio_r8(pb);
221	unsigned char es_id = avio_r8(pb);
222	uint16_t es_info_length = avio_rb16(pb);
223
224	/* remember mapping from stream id to stream type */
225	m->psm_es_type[es_id] = type;
226	/* skip program_stream_info */
227	avio_skip(pb, es_info_length);
228	es_map_length -= 4 + es_info_length;
229	}
230	avio_rb32(pb); /* crc32 */
231	return 2 + psm_length;
232	}
233
234	/* read the next PES header. Return its position in ppos
235	* (if not NULL), and its start code, pts and dts.
236	*/
237	static int mpegps_read_pes_header(AVFormatContext *s,
238	int64_t *ppos, int *pstart_code,
239	int64_t *ppts, int64_t *pdts)
240	{
241	MpegDemuxContext *m = s->priv_data;
242	int len, size, startcode, c, flags, header_len;
243	int pes_ext, ext2_len, id_ext, skip;
244	int64_t pts, dts;
245	int64_t last_sync = avio_tell(s->pb);
246
247	error_redo:
248	avio_seek(s->pb, last_sync, SEEK_SET);
249	redo:
250	/* next start code (should be immediately after) */
251	m->header_state = 0xff;
252	size = MAX_SYNC_SIZE;
253	startcode = find_next_start_code(s->pb, &size, &m->header_state);
254	last_sync = avio_tell(s->pb);
255	if (startcode < 0) {
256	if (avio_feof(s->pb))
257	return AVERROR_EOF;
258	// FIXME we should remember header_state
259	return FFERROR_REDO;
260	}
261
262	if (startcode == PACK_START_CODE)
263	goto redo;
264	if (startcode == SYSTEM_HEADER_START_CODE)
265	goto redo;
266	if (startcode == PADDING_STREAM) {
267	avio_skip(s->pb, avio_rb16(s->pb));
268	goto redo;
269	}
270	if (startcode == PRIVATE_STREAM_2) {
271	if (!m->sofdec) {
272	/* Need to detect whether this from a DVD or a 'Sofdec' stream */
273	int len = avio_rb16(s->pb);
274	int bytesread = 0;
275	uint8_t *ps2buf = av_malloc(len);
276
277	if (ps2buf) {
278	bytesread = avio_read(s->pb, ps2buf, len);
279
280	if (bytesread != len) {
281	avio_skip(s->pb, len - bytesread);
282	} else {
283	uint8_t *p = 0;
284	if (len >= 6)
285	p = memchr(ps2buf, 'S', len - 5);
286
287	if (p)
288	m->sofdec = !memcmp(p+1, "ofdec", 5);
289
290	m->sofdec -= !m->sofdec;
291
292	if (m->sofdec < 0) {
293	if (len == 980 && ps2buf[0] == 0) {
294	/* PCI structure? */
295	uint32_t startpts = AV_RB32(ps2buf + 0x0d);
296	uint32_t endpts = AV_RB32(ps2buf + 0x11);
297	uint8_t hours = ((ps2buf[0x19] >> 4) * 10) + (ps2buf[0x19] & 0x0f);
298	uint8_t mins = ((ps2buf[0x1a] >> 4) * 10) + (ps2buf[0x1a] & 0x0f);
299	uint8_t secs = ((ps2buf[0x1b] >> 4) * 10) + (ps2buf[0x1b] & 0x0f);
300
301	m->dvd = (hours <= 23 &&
302	mins <= 59 &&
303	secs <= 59 &&
304	(ps2buf[0x19] & 0x0f) < 10 &&
305	(ps2buf[0x1a] & 0x0f) < 10 &&
306	(ps2buf[0x1b] & 0x0f) < 10 &&
307	endpts >= startpts);
308	} else if (len == 1018 && ps2buf[0] == 1) {
309	/* DSI structure? */
310	uint8_t hours = ((ps2buf[0x1d] >> 4) * 10) + (ps2buf[0x1d] & 0x0f);
311	uint8_t mins = ((ps2buf[0x1e] >> 4) * 10) + (ps2buf[0x1e] & 0x0f);
312	uint8_t secs = ((ps2buf[0x1f] >> 4) * 10) + (ps2buf[0x1f] & 0x0f);
313
314	m->dvd = (hours <= 23 &&
315	mins <= 59 &&
316	secs <= 59 &&
317	(ps2buf[0x1d] & 0x0f) < 10 &&
318	(ps2buf[0x1e] & 0x0f) < 10 &&
319	(ps2buf[0x1f] & 0x0f) < 10);
320	}
321	}
322	}
323
324	av_free(ps2buf);
325
326	/* If this isn't a DVD packet or no memory
327	* could be allocated, just ignore it.
328	* If we did, move back to the start of the
329	* packet (plus 'length' field) */
330	if (!m->dvd || avio_skip(s->pb, -(len + 2)) < 0) {
331	/* Skip back failed.
332	* This packet will be lost but that can't be helped
333	* if we can't skip back
334	*/
335	goto redo;
336	}
337	} else {
338	/* No memory */
339	avio_skip(s->pb, len);
340	goto redo;
341	}
342	} else if (!m->dvd) {
343	int len = avio_rb16(s->pb);
344	avio_skip(s->pb, len);
345	goto redo;
346	}
347	}
348	if (startcode == PROGRAM_STREAM_MAP) {
349	mpegps_psm_parse(m, s->pb);
350	goto redo;
351	}
352
353	/* find matching stream */
354	if (!((startcode >= 0x1c0 && startcode <= 0x1df) ||
355	(startcode >= 0x1e0 && startcode <= 0x1ef) ||
356	(startcode == 0x1bd) ||
357	(startcode == PRIVATE_STREAM_2) ||
358	(startcode == 0x1fd)))
359	goto redo;
360	if (ppos) {
361	*ppos = avio_tell(s->pb) - 4;
362	}
363	len = avio_rb16(s->pb);
364	pts =
365	dts = AV_NOPTS_VALUE;
366	if (startcode != PRIVATE_STREAM_2)
367	{
368	/* stuffing */
369	for (;;) {
370	if (len < 1)
371	goto error_redo;
372	c = avio_r8(s->pb);
373	len--;
374	/* XXX: for MPEG-1, should test only bit 7 */
375	if (c != 0xff)
376	break;
377	}
378	if ((c & 0xc0) == 0x40) {
379	/* buffer scale & size */
380	avio_r8(s->pb);
381	c = avio_r8(s->pb);
382	len -= 2;
383	}
384	if ((c & 0xe0) == 0x20) {
385	dts =
386	pts = get_pts(s->pb, c);
387	len -= 4;
388	if (c & 0x10) {
389	dts = get_pts(s->pb, -1);
390	len -= 5;
391	}
392	} else if ((c & 0xc0) == 0x80) {
393	/* mpeg 2 PES */
394	flags = avio_r8(s->pb);
395	header_len = avio_r8(s->pb);
396	len -= 2;
397	if (header_len > len)
398	goto error_redo;
399	len -= header_len;
400	if (flags & 0x80) {
401	dts = pts = get_pts(s->pb, -1);
402	header_len -= 5;
403	if (flags & 0x40) {
404	dts = get_pts(s->pb, -1);
405	header_len -= 5;
406	}
407	}
408	if (flags & 0x3f && header_len == 0) {
409	flags &= 0xC0;
410	av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n");
411	}
412	if (flags & 0x01) { /* PES extension */
413	pes_ext = avio_r8(s->pb);
414	header_len--;
415	/* Skip PES private data, program packet sequence counter
416	* and P-STD buffer */
417	skip = (pes_ext >> 4) & 0xb;
418	skip += skip & 0x9;
419	if (pes_ext & 0x40 || skip > header_len) {
420	av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext);
421	pes_ext = skip = 0;
422	}
423	avio_skip(s->pb, skip);
424	header_len -= skip;
425
426	if (pes_ext & 0x01) { /* PES extension 2 */
427	ext2_len = avio_r8(s->pb);
428	header_len--;
429	if ((ext2_len & 0x7f) > 0) {
430	id_ext = avio_r8(s->pb);
431	if ((id_ext & 0x80) == 0)
432	startcode = ((startcode & 0xff) << 8) | id_ext;
433	header_len--;
434	}
435	}
436	}
437	if (header_len < 0)
438	goto error_redo;
439	avio_skip(s->pb, header_len);
440	} else if (c != 0xf)
441	goto redo;
442	}
443
444	if (startcode == PRIVATE_STREAM_1) {
445	startcode = avio_r8(s->pb);
446	len--;
447	}
448	if (len < 0)
449	goto error_redo;
450	if (dts != AV_NOPTS_VALUE && ppos) {
451	int i;
452	for (i = 0; i < s->nb_streams; i++) {
453	if (startcode == s->streams[i]->id &&
454	(s->pb->seekable & AVIO_SEEKABLE_NORMAL) /* index useless on streams anyway */) {
455	ff_reduce_index(s, i);
456	av_add_index_entry(s->streams[i], *ppos, dts, 0, 0,
457	AVINDEX_KEYFRAME /* FIXME keyframe? */);
458	}
459	}
460	}
461
462	*pstart_code = startcode;
463	*ppts = pts;
464	*pdts = dts;
465	return len;
466	}
467
468	static int mpegps_read_packet(AVFormatContext *s,
469	AVPacket *pkt)
470	{
471	MpegDemuxContext *m = s->priv_data;
472	AVStream *st;
473	int len, startcode, i, es_type, ret;
474	int lpcm_header_len = -1; //Init to suppress warning
475	int request_probe= 0;
476	enum AVCodecID codec_id = AV_CODEC_ID_NONE;
477	enum AVMediaType type;
478	int64_t pts, dts, dummy_pos; // dummy_pos is needed for the index building to work
479
480	redo:
481	len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts);
482	if (len < 0)
483	return len;
484
485	if (startcode >= 0x80 && startcode <= 0xcf) {
486	if (len < 4)
487	goto skip;
488
489	/* audio: skip header */
490	avio_r8(s->pb);
491	lpcm_header_len = avio_rb16(s->pb);
492	len -= 3;
493	if (startcode >= 0xb0 && startcode <= 0xbf) {
494	/* MLP/TrueHD audio has a 4-byte header */
495	avio_r8(s->pb);
496	len--;
497	}
498	}
499
500	/* now find stream */
501	for (i = 0; i < s->nb_streams; i++) {
502	st = s->streams[i];
503	if (st->id == startcode)
504	goto found;
505	}
506
507	es_type = m->psm_es_type[startcode & 0xff];
508	if (es_type == STREAM_TYPE_VIDEO_MPEG1) {
509	codec_id = AV_CODEC_ID_MPEG2VIDEO;
510	type = AVMEDIA_TYPE_VIDEO;
511	} else if (es_type == STREAM_TYPE_VIDEO_MPEG2) {
512	codec_id = AV_CODEC_ID_MPEG2VIDEO;
513	type = AVMEDIA_TYPE_VIDEO;
514	} else if (es_type == STREAM_TYPE_AUDIO_MPEG1 ||
515	es_type == STREAM_TYPE_AUDIO_MPEG2) {
516	codec_id = AV_CODEC_ID_MP3;
517	type = AVMEDIA_TYPE_AUDIO;
518	} else if (es_type == STREAM_TYPE_AUDIO_AAC) {
519	codec_id = AV_CODEC_ID_AAC;
520	type = AVMEDIA_TYPE_AUDIO;
521	} else if (es_type == STREAM_TYPE_VIDEO_MPEG4) {
522	codec_id = AV_CODEC_ID_MPEG4;
523	type = AVMEDIA_TYPE_VIDEO;
524	} else if (es_type == STREAM_TYPE_VIDEO_H264) {
525	codec_id = AV_CODEC_ID_H264;
526	type = AVMEDIA_TYPE_VIDEO;
527	} else if (es_type == STREAM_TYPE_AUDIO_AC3) {
528	codec_id = AV_CODEC_ID_AC3;
529	type = AVMEDIA_TYPE_AUDIO;
530	} else if (m->imkh_cctv && es_type == 0x91) {
531	codec_id = AV_CODEC_ID_PCM_MULAW;
532	type = AVMEDIA_TYPE_AUDIO;
533	} else if (startcode >= 0x1e0 && startcode <= 0x1ef) {
534	static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };
535	unsigned char buf[8];
536
537	avio_read(s->pb, buf, 8);
538	avio_seek(s->pb, -8, SEEK_CUR);
539	if (!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1))
540	codec_id = AV_CODEC_ID_CAVS;
541	else
542	request_probe= 1;
543	type = AVMEDIA_TYPE_VIDEO;
544	} else if (startcode == PRIVATE_STREAM_2) {
545	type = AVMEDIA_TYPE_DATA;
546	codec_id = AV_CODEC_ID_DVD_NAV;
547	} else if (startcode >= 0x1c0 && startcode <= 0x1df) {
548	type = AVMEDIA_TYPE_AUDIO;
549	if (m->sofdec > 0) {
550	codec_id = AV_CODEC_ID_ADPCM_ADX;
551	// Auto-detect AC-3
552	request_probe = 50;
553	} else if (m->imkh_cctv && startcode == 0x1c0 && len > 80) {
554	codec_id = AV_CODEC_ID_PCM_ALAW;
555	request_probe = 50;
556	} else {
557	codec_id = AV_CODEC_ID_MP2;
558	if (m->imkh_cctv)
559	request_probe = 25;
560	}
561	} else if (startcode >= 0x80 && startcode <= 0x87) {
562	type = AVMEDIA_TYPE_AUDIO;
563	codec_id = AV_CODEC_ID_AC3;
564	} else if ((startcode >= 0x88 && startcode <= 0x8f) ||
565	(startcode >= 0x98 && startcode <= 0x9f)) {
566	/* 0x90 - 0x97 is reserved for SDDS in DVD specs */
567	type = AVMEDIA_TYPE_AUDIO;
568	codec_id = AV_CODEC_ID_DTS;
569	} else if (startcode >= 0xa0 && startcode <= 0xaf) {
570	type = AVMEDIA_TYPE_AUDIO;
571	if (lpcm_header_len == 6 || startcode == 0xa1) {
572	codec_id = AV_CODEC_ID_MLP;
573	} else {
574	codec_id = AV_CODEC_ID_PCM_DVD;
575	}
576	} else if (startcode >= 0xb0 && startcode <= 0xbf) {
577	type = AVMEDIA_TYPE_AUDIO;
578	codec_id = AV_CODEC_ID_TRUEHD;
579	} else if (startcode >= 0xc0 && startcode <= 0xcf) {
580	/* Used for both AC-3 and E-AC-3 in EVOB files */
581	type = AVMEDIA_TYPE_AUDIO;
582	codec_id = AV_CODEC_ID_AC3;
583	} else if (startcode >= 0x20 && startcode <= 0x3f) {
584	type = AVMEDIA_TYPE_SUBTITLE;
585	codec_id = AV_CODEC_ID_DVD_SUBTITLE;
586	} else if (startcode >= 0xfd55 && startcode <= 0xfd5f) {
587	type = AVMEDIA_TYPE_VIDEO;
588	codec_id = AV_CODEC_ID_VC1;
589	} else {
590	skip:
591	/* skip packet */
592	avio_skip(s->pb, len);
593	goto redo;
594	}
595	/* no stream found: add a new stream */
596	st = avformat_new_stream(s, NULL);
597	if (!st)
598	goto skip;
599	st->id = startcode;
600	st->codecpar->codec_type = type;
601	st->codecpar->codec_id = codec_id;
602	if ( st->codecpar->codec_id == AV_CODEC_ID_PCM_MULAW
603	|| st->codecpar->codec_id == AV_CODEC_ID_PCM_ALAW) {
604	st->codecpar->channels = 1;
605	st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
606	st->codecpar->sample_rate = 8000;
607	}
608	st->request_probe = request_probe;
609	st->need_parsing = AVSTREAM_PARSE_FULL;
610
611	found:
612	if (st->discard >= AVDISCARD_ALL)
613	goto skip;
614	if (startcode >= 0xa0 && startcode <= 0xaf) {
615	if (st->codecpar->codec_id == AV_CODEC_ID_MLP) {
616	if (len < 6)
617	goto skip;
618	avio_skip(s->pb, 6);
619	len -=6;
620	}
621	}
622	ret = av_get_packet(s->pb, pkt, len);
623
624	pkt->pts = pts;
625	pkt->dts = dts;
626	pkt->pos = dummy_pos;
627	pkt->stream_index = st->index;
628
629	if (s->debug & FF_FDEBUG_TS)
630	av_log(s, AV_LOG_TRACE, "%d: pts=%0.3f dts=%0.3f size=%d\n",
631	pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0,
632	pkt->size);
633
634	return (ret < 0) ? ret : 0;
635	}
636
637	static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index,
638	int64_t *ppos, int64_t pos_limit)
639	{
640	int len, startcode;
641	int64_t pos, pts, dts;
642
643	pos = *ppos;
644	if (avio_seek(s->pb, pos, SEEK_SET) < 0)
645	return AV_NOPTS_VALUE;
646
647	for (;;) {
648	len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts);
649	if (len < 0) {
650	if (s->debug & FF_FDEBUG_TS)
651	av_log(s, AV_LOG_TRACE, "none (ret=%d)\n", len);
652	return AV_NOPTS_VALUE;
653	}
654	if (startcode == s->streams[stream_index]->id &&
655	dts != AV_NOPTS_VALUE) {
656	break;
657	}
658	avio_skip(s->pb, len);
659	}
660	if (s->debug & FF_FDEBUG_TS)
661	av_log(s, AV_LOG_TRACE, "pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n",
662	pos, dts, dts / 90000.0);
663	*ppos = pos;
664	return dts;
665	}
666
667	AVInputFormat ff_mpegps_demuxer = {
668	.name = "mpeg",
669	.long_name = NULL_IF_CONFIG_SMALL("MPEG-PS (MPEG-2 Program Stream)"),
670	.priv_data_size = sizeof(MpegDemuxContext),
671	.read_probe = mpegps_probe,
672	.read_header = mpegps_read_header,
673	.read_packet = mpegps_read_packet,
674	.read_timestamp = mpegps_read_dts,
675	.flags = AVFMT_SHOW_IDS | AVFMT_TS_DISCONT,
676	};
677
678	#if CONFIG_VOBSUB_DEMUXER
679
680	#define REF_STRING "# VobSub index file,"
681	#define MAX_LINE_SIZE 2048
682
683	static int vobsub_probe(AVProbeData *p)
684	{
685	if (!strncmp(p->buf, REF_STRING, sizeof(REF_STRING) - 1))
686	return AVPROBE_SCORE_MAX;
687	return 0;
688	}
689
690	static int vobsub_read_header(AVFormatContext *s)
691	{
692	int i, ret = 0, header_parsed = 0, langidx = 0;
693	MpegDemuxContext *vobsub = s->priv_data;
694	size_t fname_len;
695	char *header_str;
696	AVBPrint header;
697	int64_t delay = 0;
698	AVStream *st = NULL;
699	int stream_id = -1;
700	char id[64] = {0};
701	char alt[MAX_LINE_SIZE] = {0};
702	AVInputFormat *iformat;
703
704	if (!vobsub->sub_name) {
705	char *ext;
706	vobsub->sub_name = av_strdup(s->filename);
707	if (!vobsub->sub_name) {
708	ret = AVERROR(ENOMEM);
709	goto end;
710	}
711
712	fname_len = strlen(vobsub->sub_name);
713	ext = vobsub->sub_name - 3 + fname_len;
714	if (fname_len < 4 || *(ext - 1) != '.') {
715	av_log(s, AV_LOG_ERROR, "The input index filename is too short "
716	"to guess the associated .SUB file\n");
717	ret = AVERROR_INVALIDDATA;
718	goto end;
719	}
720	memcpy(ext, !strncmp(ext, "IDX", 3) ? "SUB" : "sub", 3);
721	av_log(s, AV_LOG_VERBOSE, "IDX/SUB: %s -> %s\n", s->filename, vobsub->sub_name);
722	}
723
724	if (!(iformat = av_find_input_format("mpeg"))) {
725	ret = AVERROR_DEMUXER_NOT_FOUND;
726	goto end;
727	}
728
729	vobsub->sub_ctx = avformat_alloc_context();
730	if (!vobsub->sub_ctx) {
731	ret = AVERROR(ENOMEM);
732	goto end;
733	}
734
735	if ((ret = ff_copy_whiteblacklists(vobsub->sub_ctx, s)) < 0)
736	goto end;
737
738	ret = avformat_open_input(&vobsub->sub_ctx, vobsub->sub_name, iformat, NULL);
739	if (ret < 0) {
740	av_log(s, AV_LOG_ERROR, "Unable to open %s as MPEG subtitles\n", vobsub->sub_name);
741	goto end;
742	}
743
744	av_bprint_init(&header, 0, AV_BPRINT_SIZE_UNLIMITED);
745	while (!avio_feof(s->pb)) {
746	char line[MAX_LINE_SIZE];
747	int len = ff_get_line(s->pb, line, sizeof(line));
748
749	if (!len)
750	break;
751
752	line[strcspn(line, "\r\n")] = 0;
753
754	if (!strncmp(line, "id:", 3)) {
755	if (sscanf(line, "id: %63[^,], index: %u", id, &stream_id) != 2) {
756	av_log(s, AV_LOG_WARNING, "Unable to parse index line '%s', "
757	"assuming 'id: und, index: 0'\n", line);
758	strcpy(id, "und");
759	stream_id = 0;
760	}
761
762	if (stream_id >= FF_ARRAY_ELEMS(vobsub->q)) {
763	av_log(s, AV_LOG_ERROR, "Maximum number of subtitles streams reached\n");
764	ret = AVERROR(EINVAL);
765	goto end;
766	}
767
768	header_parsed = 1;
769	alt[0] = '\0';
770	/* We do not create the stream immediately to avoid adding empty
771	* streams. See the following timestamp entry. */
772
773	av_log(s, AV_LOG_DEBUG, "IDX stream[%d] id=%s\n", stream_id, id);
774
775	} else if (!strncmp(line, "timestamp:", 10)) {
776	AVPacket *sub;
777	int hh, mm, ss, ms;
778	int64_t pos, timestamp;
779	const char *p = line + 10;
780
781	if (stream_id == -1) {
782	av_log(s, AV_LOG_ERROR, "Timestamp declared before any stream\n");
783	ret = AVERROR_INVALIDDATA;
784	goto end;
785	}
786
787	if (!st || st->id != stream_id) {
788	st = avformat_new_stream(s, NULL);
789	if (!st) {
790	ret = AVERROR(ENOMEM);
791	goto end;
792	}
793	st->id = stream_id;
794	st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
795	st->codecpar->codec_id = AV_CODEC_ID_DVD_SUBTITLE;
796	avpriv_set_pts_info(st, 64, 1, 1000);
797	av_dict_set(&st->metadata, "language", id, 0);
798	if (alt[0])
799	av_dict_set(&st->metadata, "title", alt, 0);
800	}
801
802	if (sscanf(p, "%02d:%02d:%02d:%03d, filepos: %"SCNx64,
803	&hh, &mm, &ss, &ms, &pos) != 5) {
804	av_log(s, AV_LOG_ERROR, "Unable to parse timestamp line '%s', "
805	"abort parsing\n", line);
806	ret = AVERROR_INVALIDDATA;
807	goto end;
808	}
809	timestamp = (hh*3600LL + mm*60LL + ss) * 1000LL + ms + delay;
810	timestamp = av_rescale_q(timestamp, av_make_q(1, 1000), st->time_base);
811
812	sub = ff_subtitles_queue_insert(&vobsub->q[s->nb_streams - 1], "", 0, 0);
813	if (!sub) {
814	ret = AVERROR(ENOMEM);
815	goto end;
816	}
817	sub->pos = pos;
818	sub->pts = timestamp;
819	sub->stream_index = s->nb_streams - 1;
820
821	} else if (!strncmp(line, "alt:", 4)) {
822	const char *p = line + 4;
823
824	while (*p == ' ')
825	p++;
826	av_log(s, AV_LOG_DEBUG, "IDX stream[%d] name=%s\n", stream_id, p);
827	av_strlcpy(alt, p, sizeof(alt));
828	header_parsed = 1;
829
830	} else if (!strncmp(line, "delay:", 6)) {
831	int sign = 1, hh = 0, mm = 0, ss = 0, ms = 0;
832	const char *p = line + 6;
833
834	while (*p == ' ')
835	p++;
836	if (*p == '-' || *p == '+') {
837	sign = *p == '-' ? -1 : 1;
838	p++;
839	}
840	sscanf(p, "%d:%d:%d:%d", &hh, &mm, &ss, &ms);
841	delay = ((hh*3600LL + mm*60LL + ss) * 1000LL + ms) * sign;
842
843	} else if (!strncmp(line, "langidx:", 8)) {
844	const char *p = line + 8;
845
846	if (sscanf(p, "%d", &langidx) != 1)
847	av_log(s, AV_LOG_ERROR, "Invalid langidx specified\n");
848
849	} else if (!header_parsed) {
850	if (line[0] && line[0] != '#')
851	av_bprintf(&header, "%s\n", line);
852	}
853	}
854
855	if (langidx < s->nb_streams)
856	s->streams[langidx]->disposition |= AV_DISPOSITION_DEFAULT;
857
858	for (i = 0; i < s->nb_streams; i++) {
859	vobsub->q[i].sort = SUB_SORT_POS_TS;
860	vobsub->q[i].keep_duplicates = 1;
861	ff_subtitles_queue_finalize(s, &vobsub->q[i]);
862	}
863
864	if (!av_bprint_is_complete(&header)) {
865	av_bprint_finalize(&header, NULL);
866	ret = AVERROR(ENOMEM);
867	goto end;
868	}
869	av_bprint_finalize(&header, &header_str);
870	for (i = 0; i < s->nb_streams; i++) {
871	AVStream *sub_st = s->streams[i];
872	sub_st->codecpar->extradata = av_strdup(header_str);
873	sub_st->codecpar->extradata_size = header.len;
874	}
875	av_free(header_str);
876
877	end:
878	return ret;
879	}
880
881	static int vobsub_read_packet(AVFormatContext *s, AVPacket *pkt)
882	{
883	MpegDemuxContext *vobsub = s->priv_data;
884	FFDemuxSubtitlesQueue *q;
885	AVIOContext *pb = vobsub->sub_ctx->pb;
886	int ret, psize, total_read = 0, i;
887	AVPacket idx_pkt;
888
889	int64_t min_ts = INT64_MAX;
890	int sid = 0;
891	for (i = 0; i < s->nb_streams; i++) {
892	FFDemuxSubtitlesQueue *tmpq = &vobsub->q[i];
893	int64_t ts;
894	av_assert0(tmpq->nb_subs);
895	ts = tmpq->subs[tmpq->current_sub_idx].pts;
896	if (ts < min_ts) {
897	min_ts = ts;
898	sid = i;
899	}
900	}
901	q = &vobsub->q[sid];
902	ret = ff_subtitles_queue_read_packet(q, &idx_pkt);
903	if (ret < 0)
904	return ret;
905
906	/* compute maximum packet size using the next packet position. This is
907	* useful when the len in the header is non-sense */
908	if (q->current_sub_idx < q->nb_subs) {
909	psize = q->subs[q->current_sub_idx].pos - idx_pkt.pos;
910	} else {
911	int64_t fsize = avio_size(pb);
912	psize = fsize < 0 ? 0xffff : fsize - idx_pkt.pos;
913	}
914
915	avio_seek(pb, idx_pkt.pos, SEEK_SET);
916
917	av_init_packet(pkt);
918	pkt->size = 0;
919	pkt->data = NULL;
920
921	do {
922	int n, to_read, startcode;
923	int64_t pts, dts;
924	int64_t old_pos = avio_tell(pb), new_pos;
925	int pkt_size;
926
927	ret = mpegps_read_pes_header(vobsub->sub_ctx, NULL, &startcode, &pts, &dts);
928	if (ret < 0) {
929	if (pkt->size) // raise packet even if incomplete
930	break;
931	goto fail;
932	}
933	to_read = ret & 0xffff;
934	new_pos = avio_tell(pb);
935	pkt_size = ret + (new_pos - old_pos);
936
937	/* this prevents reads above the current packet */
938	if (total_read + pkt_size > psize)
939	break;
940	total_read += pkt_size;
941
942	/* the current chunk doesn't match the stream index (unlikely) */
943	if ((startcode & 0x1f) != s->streams[idx_pkt.stream_index]->id)
944	break;
945
946	ret = av_grow_packet(pkt, to_read);
947	if (ret < 0)
948	goto fail;
949
950	n = avio_read(pb, pkt->data + (pkt->size - to_read), to_read);
951	if (n < to_read)
952	pkt->size -= to_read - n;
953	} while (total_read < psize);
954
955	pkt->pts = pkt->dts = idx_pkt.pts;
956	pkt->pos = idx_pkt.pos;
957	pkt->stream_index = idx_pkt.stream_index;
958
959	av_packet_unref(&idx_pkt);
960	return 0;
961
962	fail:
963	av_packet_unref(pkt);
964	av_packet_unref(&idx_pkt);
965	return ret;
966	}
967
968	static int vobsub_read_seek(AVFormatContext *s, int stream_index,
969	int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
970	{
971	MpegDemuxContext *vobsub = s->priv_data;
972
973	/* Rescale requested timestamps based on the first stream (timebase is the
974	* same for all subtitles stream within a .idx/.sub). Rescaling is done just
975	* like in avformat_seek_file(). */
976	if (stream_index == -1 && s->nb_streams != 1) {
977	int i, ret = 0;
978	AVRational time_base = s->streams[0]->time_base;
979	ts = av_rescale_q(ts, AV_TIME_BASE_Q, time_base);
980	min_ts = av_rescale_rnd(min_ts, time_base.den,
981	time_base.num * (int64_t)AV_TIME_BASE,
982	AV_ROUND_UP | AV_ROUND_PASS_MINMAX);
983	max_ts = av_rescale_rnd(max_ts, time_base.den,
984	time_base.num * (int64_t)AV_TIME_BASE,
985	AV_ROUND_DOWN | AV_ROUND_PASS_MINMAX);
986	for (i = 0; i < s->nb_streams; i++) {
987	int r = ff_subtitles_queue_seek(&vobsub->q[i], s, stream_index,
988	min_ts, ts, max_ts, flags);
989	if (r < 0)
990	ret = r;
991	}
992	return ret;
993	}
994
995	if (stream_index == -1) // only 1 stream
996	stream_index = 0;
997	return ff_subtitles_queue_seek(&vobsub->q[stream_index], s, stream_index,
998	min_ts, ts, max_ts, flags);
999	}
1000
1001	static int vobsub_read_close(AVFormatContext *s)
1002	{
1003	int i;
1004	MpegDemuxContext *vobsub = s->priv_data;
1005
1006	for (i = 0; i < s->nb_streams; i++)
1007	ff_subtitles_queue_clean(&vobsub->q[i]);
1008	if (vobsub->sub_ctx)
1009	avformat_close_input(&vobsub->sub_ctx);
1010	return 0;
1011	}
1012
1013	static const AVOption options[] = {
1014	{ "sub_name", "URI for .sub file", offsetof(MpegDemuxContext, sub_name), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
1015	{ NULL }
1016	};
1017
1018	static const AVClass vobsub_demuxer_class = {
1019	.class_name = "vobsub",
1020	.item_name = av_default_item_name,
1021	.option = options,
1022	.version = LIBAVUTIL_VERSION_INT,
1023	};
1024
1025	AVInputFormat ff_vobsub_demuxer = {
1026	.name = "vobsub",
1027	.long_name = NULL_IF_CONFIG_SMALL("VobSub subtitle format"),
1028	.priv_data_size = sizeof(MpegDemuxContext),
1029	.read_probe = vobsub_probe,
1030	.read_header = vobsub_read_header,
1031	.read_packet = vobsub_read_packet,
1032	.read_seek2 = vobsub_read_seek,
1033	.read_close = vobsub_read_close,
1034	.flags = AVFMT_SHOW_IDS,
1035	.extensions = "idx",
1036	.priv_class = &vobsub_demuxer_class,
1037	};
1038	#endif
1039