]> git.sesse.net Git - vlc/blob - modules/demux/ps.c
* modules/demux/ps.c: fixed breakage
[vlc] / modules / demux / ps.c
1 /*****************************************************************************
2  * ps.c: Program Stream demux module for VLC.
3  *****************************************************************************
4  * Copyright (C) 2004 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22  *****************************************************************************/
23
24 /*****************************************************************************
25  * Preamble
26  *****************************************************************************/
27 #include <stdlib.h>                                      /* malloc(), free() */
28
29 #include <vlc/vlc.h>
30 #include <vlc/input.h>
31
32 #include "ps.h"
33
34 /* TODO:
35  *  - re-add pre-scanning.
36  *  - ...
37  */
38
39 #define TIME_TEXT N_("Trust MPEG timestamps")
40 #define TIME_LONGTEXT N_("Normally we use the timestamps of the MPEG files " \
41     "to calculate position and duration. However sometimes this might not " \
42     "be usable. Disable this option to calculate from the bitrate instead." )
43
44 /*****************************************************************************
45  * Module descriptor
46  *****************************************************************************/
47 static int  Open   ( vlc_object_t * );
48 static int  OpenAlt( vlc_object_t * );
49 static void Close  ( vlc_object_t * );
50
51 vlc_module_begin();
52     set_description( _("MPEG-PS demuxer") );
53     set_category( CAT_INPUT );
54     set_subcategory( SUBCAT_INPUT_DEMUX );
55     set_capability( "demux2", 1 );
56     set_callbacks( Open, Close );
57     add_shortcut( "ps" );
58
59     add_integer( "ps-trust-timestamps", VLC_TRUE, NULL, TIME_TEXT,
60                  TIME_LONGTEXT, VLC_TRUE );
61
62     add_submodule();
63     set_description( _("MPEG-PS demuxer") );
64     set_capability( "demux2", 9 );
65     set_callbacks( OpenAlt, Close );
66 vlc_module_end();
67
68 /*****************************************************************************
69  * Local prototypes
70  *****************************************************************************/
71
72 struct demux_sys_t
73 {
74     ps_psm_t    psm;
75     ps_track_t  tk[PS_TK_COUNT];
76
77     int64_t     i_scr;
78     int         i_mux_rate;
79     int64_t     i_length;
80     int         i_time_track;
81     int64_t     i_current_pts;
82
83     vlc_bool_t  b_lost_sync;
84     vlc_bool_t  b_have_pack;
85     vlc_bool_t  b_seekable;
86 };
87
88 static int Demux  ( demux_t *p_demux );
89 static int Control( demux_t *p_demux, int i_query, va_list args );
90
91 static int      ps_pkt_resynch( stream_t *, uint32_t *pi_code );
92 static block_t *ps_pkt_read   ( stream_t *, uint32_t i_code );
93
94 /*****************************************************************************
95  * Open
96  *****************************************************************************/
97 static int Open( vlc_object_t *p_this )
98 {
99     demux_t     *p_demux = (demux_t*)p_this;
100     demux_sys_t *p_sys;
101
102     uint8_t     *p_peek;
103
104     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
105     {
106         msg_Err( p_demux, "cannot peek" );
107         return VLC_EGENERIC;
108     }
109
110     if( p_peek[0] != 0 || p_peek[1] != 0 ||
111         p_peek[2] != 1 || p_peek[3] < 0xb9 )
112     {
113         msg_Warn( p_demux, "this does not look like an MPEG PS stream, "
114                   "continuing anyway" );
115     }
116
117     /* Fill p_demux field */
118     p_demux->pf_demux = Demux;
119     p_demux->pf_control = Control;
120     p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
121
122     /* Init p_sys */
123     p_sys->i_mux_rate = 0;
124     p_sys->i_scr      = -1;
125     p_sys->i_length   = -1;
126     p_sys->i_current_pts = (mtime_t) 0;
127     p_sys->i_time_track = -1;
128     
129     p_sys->b_lost_sync = VLC_FALSE;
130     p_sys->b_have_pack = VLC_FALSE;
131     p_sys->b_seekable  = VLC_FALSE;
132
133     stream_Control( p_demux->s, STREAM_CAN_SEEK, &p_sys->b_seekable );
134
135     ps_psm_init( &p_sys->psm );
136     ps_track_init( p_sys->tk );
137
138     /* TODO prescanning of ES */
139
140     return VLC_SUCCESS;
141 }
142
143 static int OpenAlt( vlc_object_t *p_this )
144 {
145     demux_t *p_demux = (demux_t*)p_this;
146     uint8_t *p_peek;
147
148     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
149     {
150         msg_Err( p_demux, "cannot peek" );
151         return VLC_EGENERIC;
152     }
153
154     if( p_peek[0] != 0 || p_peek[1] != 0 ||
155         p_peek[2] != 1 || p_peek[3] < 0xb9 )
156     {
157         if( !p_demux->b_force ) return VLC_EGENERIC;
158     }
159
160     return Open( p_this );
161 }
162
163 /*****************************************************************************
164  * Close
165  *****************************************************************************/
166 static void Close( vlc_object_t *p_this )
167 {
168     demux_t     *p_demux = (demux_t*)p_this;
169     demux_sys_t *p_sys = p_demux->p_sys;
170     int i;
171
172     for( i = 0; i < PS_TK_COUNT; i++ )
173     {
174         ps_track_t *tk = &p_sys->tk[i];
175         if( tk->b_seen )
176         {
177             es_format_Clean( &tk->fmt );
178             if( tk->es ) es_out_Del( p_demux->out, tk->es );
179         }
180     }
181
182     ps_psm_destroy( &p_sys->psm );
183
184     free( p_sys );
185 }
186
187 static int Demux2( demux_t *p_demux )
188 {
189     demux_sys_t *p_sys = p_demux->p_sys;
190     int i_ret, i_id;
191     uint32_t i_code;
192     block_t *p_pkt;
193
194     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
195     if( i_ret < 0 )
196     {
197         return 0;
198     }
199     else if( i_ret == 0 )
200     {
201         if( !p_sys->b_lost_sync )
202             msg_Warn( p_demux, "garbage at input, trying to resync..." );
203
204         p_sys->b_lost_sync = VLC_TRUE;
205         return 1;
206     }
207
208     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
209     p_sys->b_lost_sync = VLC_FALSE;
210
211     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
212     {
213         return 0;
214     }
215     if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
216     {
217         ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
218         if( !ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
219         {
220             tk->i_last_pts = p_pkt->i_pts;
221         }
222     }
223     block_Release( p_pkt );
224     return 1;
225 }
226
227 static void FindLength( demux_t *p_demux )
228 {
229     demux_sys_t *p_sys = p_demux->p_sys;
230     int64_t i_current_pos = -1, i_size = 0, i_end = 0;
231     int i;
232
233     if( !var_CreateGetInteger( p_demux, "ps-trust-timestamps" ) )
234         return;
235
236     if( p_sys->i_length == -1 ) /* First time */
237     {
238         i_current_pos = stream_Tell( p_demux->s );
239         i_size = stream_Size( p_demux->s );
240         i_end = __MAX( 0, __MIN( 100000, i_size ) );
241         stream_Seek( p_demux->s, stream_Size( p_demux->s ) - i_end );
242     
243         while( Demux2( p_demux ) > 0 && !p_demux->b_die ) ;
244     }
245
246     for( i = 0; i < PS_TK_COUNT; i++ )
247     {
248         ps_track_t *tk = &p_sys->tk[i];
249         if( tk->b_seen && tk->i_first_pts > 0 && tk->i_last_pts > 0 )
250             if( tk->i_last_pts > tk->i_first_pts )
251             {
252                 int64_t i_length = (int64_t)tk->i_last_pts - tk->i_first_pts;
253                 if( i_length > p_sys->i_length )
254                 {
255                     p_sys->i_length = i_length;
256                     p_sys->i_time_track = i;
257                 }
258             }
259     }
260     if( i_current_pos >= 0 ) stream_Seek( p_demux->s, i_current_pos );
261 }
262
263 /*****************************************************************************
264  * Demux:
265  *****************************************************************************/
266 static int Demux( demux_t *p_demux )
267 {
268     demux_sys_t *p_sys = p_demux->p_sys;
269     int i_ret, i_id, i_mux_rate;
270     uint32_t i_code;
271     block_t *p_pkt;
272
273     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
274     if( i_ret < 0 )
275     {
276         return 0;
277     }
278     else if( i_ret == 0 )
279     {
280         if( !p_sys->b_lost_sync )
281             msg_Warn( p_demux, "garbage at input, trying to resync..." );
282
283         p_sys->b_lost_sync = VLC_TRUE;
284         return 1;
285     }
286
287     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
288     p_sys->b_lost_sync = VLC_FALSE;
289
290     if( p_sys->b_seekable && p_sys->i_length <= 0 )
291         FindLength( p_demux );
292
293     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
294     {
295         return 0;
296     }
297
298     switch( i_code )
299     {
300     case 0x1b9:
301         block_Release( p_pkt );
302         break;
303
304     case 0x1ba:
305         if( !ps_pkt_parse_pack( p_pkt, &p_sys->i_scr, &i_mux_rate ) )
306         {
307             if( !p_sys->b_have_pack ) p_sys->b_have_pack = VLC_TRUE;
308             /* done later on to work around bad vcd/svcd streams */
309             /* es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr ); */
310             if( i_mux_rate > 0 ) p_sys->i_mux_rate = i_mux_rate;
311         }
312         block_Release( p_pkt );
313         break;
314
315     case 0x1bb:
316         if( !ps_pkt_parse_system( p_pkt, &p_sys->psm, p_sys->tk ) )
317         {
318             int i;
319             for( i = 0; i < PS_TK_COUNT; i++ )
320             {
321                 ps_track_t *tk = &p_sys->tk[i];
322
323                 if( tk->b_seen && !tk->es && tk->fmt.i_cat != UNKNOWN_ES )
324                 {
325                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
326                 }
327             }
328         }
329         block_Release( p_pkt );
330         break;
331
332     case 0x1bc:
333         if( p_sys->psm.i_version == 0xFFFF )
334             msg_Dbg( p_demux, "contains a PSM");
335
336         ps_psm_fill( &p_sys->psm, p_pkt, p_sys->tk, p_demux->out );
337         block_Release( p_pkt );
338         break;
339
340     default:
341         if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
342         {
343             vlc_bool_t b_new = VLC_FALSE;
344             ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
345
346             if( !tk->b_seen )
347             {
348                 if( !ps_track_fill( tk, &p_sys->psm, i_id ) )
349                 {
350                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
351                     b_new = VLC_TRUE;
352                 }
353                 else
354                 {
355                     msg_Dbg( p_demux, "es id=0x%x format unknown", i_id );
356                 }
357                 tk->b_seen = VLC_TRUE;
358             }
359
360             /* The popular VCD/SVCD subtitling WinSubMux does not
361              * renumber the SCRs when merging subtitles into the PES */
362             if( tk->b_seen &&
363                 ( tk->fmt.i_codec == VLC_FOURCC('o','g','t',' ') ||
364                   tk->fmt.i_codec == VLC_FOURCC('c','v','d',' ') ) )
365             {
366                 p_sys->i_scr = -1;
367             }
368
369             if( p_sys->i_scr > 0 )
370                 es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr );
371
372             p_sys->i_scr = -1;
373
374             if( tk->b_seen && tk->es &&
375                 !ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
376             {
377                 if( !b_new && !p_sys->b_have_pack && tk->fmt.i_cat == AUDIO_ES && p_pkt->i_pts > 0 )
378                 {
379                     /* A hack to sync the A/V on PES files. */
380                     msg_Dbg( p_demux, "force SCR: %lld", p_pkt->i_pts );
381                     es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_pkt->i_pts );
382                 }
383
384                 if( !tk->i_first_pts && p_pkt->i_pts > 0 )
385                 {
386                     tk->i_first_pts = p_pkt->i_pts;
387                     p_sys->i_length = 0;
388                 }
389                 if( (int64_t)p_pkt->i_pts > p_sys->i_current_pts )
390                 {
391                     p_sys->i_current_pts = (int64_t)p_pkt->i_pts;
392                 }
393
394                 es_out_Send( p_demux->out, tk->es, p_pkt );
395             }
396             else
397             {
398                 block_Release( p_pkt );
399             }
400         }
401         else
402         {
403             block_Release( p_pkt );
404         }
405         break;
406     }
407
408     return 1;
409 }
410
411 /*****************************************************************************
412  * Control:
413  *****************************************************************************/
414 static int Control( demux_t *p_demux, int i_query, va_list args )
415 {
416     demux_sys_t *p_sys = p_demux->p_sys;
417     double f, *pf;
418     int64_t i64, *pi64;
419
420     switch( i_query )
421     {
422         case DEMUX_GET_POSITION:
423             pf = (double*) va_arg( args, double* );
424             i64 = stream_Size( p_demux->s );
425             if( i64 > 0 )
426             {
427                 *pf = (double)stream_Tell( p_demux->s ) / (double)i64;
428             }
429             else
430             {
431                 *pf = 0.0;
432             }
433             return VLC_SUCCESS;
434
435         case DEMUX_SET_POSITION:
436             f = (double) va_arg( args, double );
437             i64 = stream_Size( p_demux->s );
438             p_sys->i_current_pts = 0;
439             es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
440
441             return stream_Seek( p_demux->s, (int64_t)(i64 * f) );
442
443         case DEMUX_GET_TIME:
444             pi64 = (int64_t*)va_arg( args, int64_t * );
445             if( p_sys->i_time_track >= 0 && p_sys->i_current_pts > 0 )
446             {
447                 *pi64 = p_sys->i_current_pts - p_sys->tk[p_sys->i_time_track].i_first_pts;
448                 return VLC_SUCCESS;
449             }
450             if( p_sys->i_mux_rate > 0 )
451             {
452                 *pi64 = (int64_t)1000000 * ( stream_Tell( p_demux->s ) / 50 ) /
453                     p_sys->i_mux_rate;
454                 return VLC_SUCCESS;
455             }
456             *pi64 = 0;
457             return VLC_EGENERIC;
458
459         case DEMUX_GET_LENGTH:
460             pi64 = (int64_t*)va_arg( args, int64_t * );
461             if( p_sys->i_length > 0 )
462             {
463                 *pi64 = p_sys->i_length;
464                 return VLC_SUCCESS;
465             }
466             else if( p_sys->i_mux_rate > 0 )
467             {
468                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) /
469                     p_sys->i_mux_rate;
470                 return VLC_SUCCESS;
471             }
472             *pi64 = 0;
473             return VLC_EGENERIC;
474
475         case DEMUX_SET_TIME:
476         case DEMUX_GET_FPS:
477         default:
478             return VLC_EGENERIC;
479     }
480 }
481
482 /*****************************************************************************
483  * Divers:
484  *****************************************************************************/
485
486 /* PSResynch: resynch on a system starcode
487  *  It doesn't skip more than 512 bytes
488  *  -1 -> error, 0 -> not synch, 1 -> ok
489  */
490 static int ps_pkt_resynch( stream_t *s, uint32_t *pi_code )
491 {
492     uint8_t *p_peek;
493     int     i_peek;
494     int     i_skip;
495
496     if( stream_Peek( s, &p_peek, 4 ) < 4 )
497     {
498         return -1;
499     }
500     if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
501         p_peek[3] >= 0xb9 )
502     {
503         *pi_code = 0x100 | p_peek[3];
504         return 1;
505     }
506
507     if( ( i_peek = stream_Peek( s, &p_peek, 512 ) ) < 4 )
508     {
509         return -1;
510     }
511     i_skip = 0;
512
513     for( ;; )
514     {
515         if( i_peek < 4 )
516         {
517             break;
518         }
519         if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
520             p_peek[3] >= 0xb9 )
521         {
522             *pi_code = 0x100 | p_peek[3];
523             return stream_Read( s, NULL, i_skip ) == i_skip ? 1 : -1;
524         }
525
526         p_peek++;
527         i_peek--;
528         i_skip++;
529     }
530     return stream_Read( s, NULL, i_skip ) == i_skip ? 0 : -1;
531 }
532
533 static block_t *ps_pkt_read( stream_t *s, uint32_t i_code )
534 {
535     uint8_t *p_peek;
536     int      i_peek = stream_Peek( s, &p_peek, 14 );
537     int      i_size = ps_pkt_size( p_peek, i_peek );
538
539     if( i_size <= 6 && p_peek[3] > 0xba )
540     {
541         /* Special case, search the next start code */
542         i_size = 6;
543         for( ;; )
544         {
545             i_peek = stream_Peek( s, &p_peek, i_size + 1024 );
546             if( i_peek <= i_size + 4 )
547             {
548                 return NULL;
549             }
550             while( i_size <= i_peek - 4 )
551             {
552                 if( p_peek[i_size] == 0x00 && p_peek[i_size+1] == 0x00 &&
553                     p_peek[i_size+2] == 0x01 && p_peek[i_size+3] >= 0xb9 )
554                 {
555                     return stream_Block( s, i_size );
556                 }
557                 i_size++;
558             }
559         }
560     }
561     else
562     {
563         /* Normal case */
564         return stream_Block( s, i_size );
565     }
566
567     return NULL;
568 }