git.sesse.net Git - vlc/blob - modules/demux/ps.c

   1 /*****************************************************************************
   2  * ps.c: Program Stream demux module for VLC.
   3  *****************************************************************************
   4  * Copyright (C) 2004-2009 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
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_demux.h>
  35
  36 #include "ps.h"
  37
  38 /* TODO:
  39  *  - re-add pre-scanning.
  40  *  - ...
  41  */
  42
  43 #define TIME_TEXT N_("Trust MPEG timestamps")
  44 #define TIME_LONGTEXT N_("Normally we use the timestamps of the MPEG files " \
  45     "to calculate position and duration. However sometimes this might not " \
  46     "be usable. Disable this option to calculate from the bitrate instead." )
  47
  48 /*****************************************************************************
  49  * Module descriptor
  50  *****************************************************************************/
  51 static int  OpenForce( vlc_object_t * );
  52 static int  Open   ( vlc_object_t * );
  53 static void Close  ( vlc_object_t * );
  54
  55 vlc_module_begin ()
  56     set_description( N_("MPEG-PS demuxer") )
  57     set_shortname( N_("PS") )
  58     set_category( CAT_INPUT )
  59     set_subcategory( SUBCAT_INPUT_DEMUX )
  60     set_capability( "demux", 1 )
  61     set_callbacks( OpenForce, Close )
  62     add_shortcut( "ps" )
  63
  64     add_bool( "ps-trust-timestamps", true, NULL, TIME_TEXT,
  65                  TIME_LONGTEXT, true )
  66         change_safe ()
  67
  68     add_submodule ()
  69     set_description( N_("MPEG-PS demuxer") )
  70     set_capability( "demux", 8 )
  71     set_callbacks( Open, Close )
  72     add_shortcut( "ps" )
  73 vlc_module_end ()
  74
  75 /*****************************************************************************
  76  * Local prototypes
  77  *****************************************************************************/
  78
  79 struct demux_sys_t
  80 {
  81     ps_psm_t    psm;
  82     ps_track_t  tk[PS_TK_COUNT];
  83
  84     int64_t     i_scr;
  85     int         i_mux_rate;
  86     int64_t     i_length;
  87     int         i_time_track;
  88     int64_t     i_current_pts;
  89
  90     int         i_aob_mlp_count;
  91
  92     bool  b_lost_sync;
  93     bool  b_have_pack;
  94     bool  b_seekable;
  95 };
  96
  97 static int Demux  ( demux_t *p_demux );
  98 static int Control( demux_t *p_demux, int i_query, va_list args );
  99
 100 static int      ps_pkt_resynch( stream_t *, uint32_t *pi_code );
 101 static block_t *ps_pkt_read   ( stream_t *, uint32_t i_code );
 102
 103 /*****************************************************************************
 104  * Open
 105  *****************************************************************************/
 106 static int OpenCommon( vlc_object_t *p_this, bool b_force )
 107 {
 108     demux_t     *p_demux = (demux_t*)p_this;
 109     demux_sys_t *p_sys;
 110
 111     const uint8_t *p_peek;
 112
 113     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
 114     {
 115         msg_Err( p_demux, "cannot peek" );
 116         return VLC_EGENERIC;
 117     }
 118
 119     if( memcmp( p_peek, "\x00\x00\x01", 3 ) || ( p_peek[3] < 0xb9 ) )
 120     {
 121         if( !b_force )
 122             return VLC_EGENERIC;
 123
 124         msg_Warn( p_demux, "this does not look like an MPEG PS stream, "
 125                   "continuing anyway" );
 126     }
 127
 128     /* Fill p_demux field */
 129     p_demux->pf_demux = Demux;
 130     p_demux->pf_control = Control;
 131     p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
 132     if( !p_sys ) return VLC_ENOMEM;
 133
 134     /* Init p_sys */
 135     p_sys->i_mux_rate = 0;
 136     p_sys->i_scr      = -1;
 137     p_sys->i_length   = -1;
 138     p_sys->i_current_pts = (mtime_t) 0;
 139     p_sys->i_time_track = -1;
 140     p_sys->i_aob_mlp_count = 0;
 141
 142     p_sys->b_lost_sync = false;
 143     p_sys->b_have_pack = false;
 144     p_sys->b_seekable  = false;
 145
 146     stream_Control( p_demux->s, STREAM_CAN_SEEK, &p_sys->b_seekable );
 147
 148     ps_psm_init( &p_sys->psm );
 149     ps_track_init( p_sys->tk );
 150
 151     /* TODO prescanning of ES */
 152
 153     return VLC_SUCCESS;
 154 }
 155
 156 static int OpenForce( vlc_object_t *p_this )
 157 {
 158     return OpenCommon( p_this, true );
 159 }
 160
 161 static int Open( vlc_object_t *p_this )
 162 {
 163     return OpenCommon( p_this, ((demux_t *)p_this)->b_force );
 164 }
 165
 166 /*****************************************************************************
 167  * Close
 168  *****************************************************************************/
 169 static void Close( vlc_object_t *p_this )
 170 {
 171     demux_t     *p_demux = (demux_t*)p_this;
 172     demux_sys_t *p_sys = p_demux->p_sys;
 173     int i;
 174
 175     for( i = 0; i < PS_TK_COUNT; i++ )
 176     {
 177         ps_track_t *tk = &p_sys->tk[i];
 178         if( tk->b_seen )
 179         {
 180             es_format_Clean( &tk->fmt );
 181             if( tk->es ) es_out_Del( p_demux->out, tk->es );
 182         }
 183     }
 184
 185     ps_psm_destroy( &p_sys->psm );
 186
 187     free( p_sys );
 188 }
 189
 190 static int Demux2( demux_t *p_demux, bool b_end )
 191 {
 192     demux_sys_t *p_sys = p_demux->p_sys;
 193     int i_ret, i_id;
 194     uint32_t i_code;
 195     block_t *p_pkt;
 196
 197     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
 198     if( i_ret < 0 )
 199     {
 200         return 0;
 201     }
 202     else if( i_ret == 0 )
 203     {
 204         if( !p_sys->b_lost_sync )
 205             msg_Warn( p_demux, "garbage at input, trying to resync..." );
 206
 207         p_sys->b_lost_sync = true;
 208         return 1;
 209     }
 210
 211     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
 212     p_sys->b_lost_sync = false;
 213
 214     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
 215     {
 216         return 0;
 217     }
 218     if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
 219     {
 220         ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
 221         if( !ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
 222         {
 223             if( b_end && p_pkt->i_pts > tk->i_last_pts )
 224             {
 225                 tk->i_last_pts = p_pkt->i_pts;
 226             }
 227             else if ( tk->i_first_pts == -1 )
 228             {
 229                 tk->i_first_pts = p_pkt->i_pts;
 230             }
 231         }
 232     }
 233     block_Release( p_pkt );
 234     return 1;
 235 }
 236
 237 static void FindLength( demux_t *p_demux )
 238 {
 239     demux_sys_t *p_sys = p_demux->p_sys;
 240     int64_t i_current_pos = -1, i_size = 0, i_end = 0;
 241     int i;
 242
 243     if( !var_CreateGetBool( p_demux, "ps-trust-timestamps" ) )
 244         return;
 245
 246     if( p_sys->i_length == -1 ) /* First time */
 247     {
 248         p_sys->i_length = 0;
 249         /* Check beginning */
 250         i = 0;
 251         i_current_pos = stream_Tell( p_demux->s );
 252         while( vlc_object_alive (p_demux) && i < 40 && Demux2( p_demux, false ) > 0 ) i++;
 253
 254         /* Check end */
 255         i_size = stream_Size( p_demux->s );
 256         i_end = __MAX( 0, __MIN( 200000, i_size ) );
 257         stream_Seek( p_demux->s, i_size - i_end );
 258         i = 0;
 259
 260         while( vlc_object_alive (p_demux) && i < 40 && Demux2( p_demux, true ) > 0 );
 261         if( i_current_pos >= 0 ) stream_Seek( p_demux->s, i_current_pos );
 262     }
 263
 264     for( i = 0; i < PS_TK_COUNT; i++ )
 265     {
 266         ps_track_t *tk = &p_sys->tk[i];
 267         if( tk->i_first_pts >= 0 && tk->i_last_pts > 0 )
 268             if( tk->i_last_pts > tk->i_first_pts )
 269             {
 270                 int64_t i_length = (int64_t)tk->i_last_pts - tk->i_first_pts;
 271                 if( i_length > p_sys->i_length )
 272                 {
 273                     p_sys->i_length = i_length;
 274                     p_sys->i_time_track = i;
 275                     msg_Dbg( p_demux, "we found a length of: %"PRId64, p_sys->i_length );
 276                 }
 277             }
 278     }
 279 }
 280
 281 /*****************************************************************************
 282  * Demux:
 283  *****************************************************************************/
 284 static int Demux( demux_t *p_demux )
 285 {
 286     demux_sys_t *p_sys = p_demux->p_sys;
 287     int i_ret, i_id, i_mux_rate;
 288     uint32_t i_code;
 289     block_t *p_pkt;
 290
 291     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
 292     if( i_ret < 0 )
 293     {
 294         return 0;
 295     }
 296     else if( i_ret == 0 )
 297     {
 298         if( !p_sys->b_lost_sync )
 299             msg_Warn( p_demux, "garbage at input, trying to resync..." );
 300
 301         p_sys->b_lost_sync = true;
 302         return 1;
 303     }
 304
 305     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
 306     p_sys->b_lost_sync = false;
 307
 308     if( p_sys->i_length < 0 && p_sys->b_seekable )
 309         FindLength( p_demux );
 310
 311     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
 312     {
 313         return 0;
 314     }
 315
 316     switch( i_code )
 317     {
 318     case 0x1b9:
 319         block_Release( p_pkt );
 320         break;
 321
 322     case 0x1ba:
 323         if( !ps_pkt_parse_pack( p_pkt, &p_sys->i_scr, &i_mux_rate ) )
 324         {
 325             if( !p_sys->b_have_pack ) p_sys->b_have_pack = true;
 326             /* done later on to work around bad vcd/svcd streams */
 327             /* es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr ); */
 328             if( i_mux_rate > 0 ) p_sys->i_mux_rate = i_mux_rate;
 329         }
 330         block_Release( p_pkt );
 331         break;
 332
 333     case 0x1bb:
 334         if( !ps_pkt_parse_system( p_pkt, &p_sys->psm, p_sys->tk ) )
 335         {
 336             int i;
 337             for( i = 0; i < PS_TK_COUNT; i++ )
 338             {
 339                 ps_track_t *tk = &p_sys->tk[i];
 340
 341                 if( tk->b_seen && !tk->es && tk->fmt.i_cat != UNKNOWN_ES )
 342                 {
 343                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 344                 }
 345             }
 346         }
 347         block_Release( p_pkt );
 348         break;
 349
 350     case 0x1bc:
 351         if( p_sys->psm.i_version == 0xFFFF )
 352             msg_Dbg( p_demux, "contains a PSM");
 353
 354         ps_psm_fill( &p_sys->psm, p_pkt, p_sys->tk, p_demux->out );
 355         block_Release( p_pkt );
 356         break;
 357
 358     default:
 359         if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
 360         {
 361             /* Small heuristic to improve MLP detection from AOB */
 362             if( i_id == 0xa001 &&
 363                 p_sys->i_aob_mlp_count < 500 )
 364             {
 365                 p_sys->i_aob_mlp_count++;
 366             }
 367             else if( i_id == 0xbda1 &&
 368                      p_sys->i_aob_mlp_count > 0 )
 369             {
 370                 p_sys->i_aob_mlp_count--;
 371                 i_id = 0xa001;
 372             }
 373
 374             bool b_new = false;
 375             ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
 376
 377             if( !tk->b_seen )
 378             {
 379                 if( !ps_track_fill( tk, &p_sys->psm, i_id ) )
 380                 {
 381                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 382                     b_new = true;
 383                 }
 384                 else
 385                 {
 386                     msg_Dbg( p_demux, "es id=0x%x format unknown", i_id );
 387                 }
 388                 tk->b_seen = true;
 389             }
 390
 391             /* The popular VCD/SVCD subtitling WinSubMux does not
 392              * renumber the SCRs when merging subtitles into the PES */
 393             if( tk->b_seen &&
 394                 ( tk->fmt.i_codec == VLC_CODEC_OGT ||
 395                   tk->fmt.i_codec == VLC_CODEC_CVD ) )
 396             {
 397                 p_sys->i_scr = -1;
 398             }
 399
 400             if( p_sys->i_scr >= 0 )
 401                 es_out_Control( p_demux->out, ES_OUT_SET_PCR, VLC_TS_0 + p_sys->i_scr );
 402
 403             p_sys->i_scr = -1;
 404
 405             if( tk->b_seen && tk->es &&
 406                 (
 407 #ifdef ZVBI_COMPILED /* FIXME!! */
 408                 tk->fmt.i_codec == VLC_CODEC_TELETEXT ||
 409 #endif
 410                 !ps_pkt_parse_pes( p_pkt, tk->i_skip ) ) )
 411             {
 412                 if( !b_new && !p_sys->b_have_pack &&
 413                     (tk->fmt.i_cat == AUDIO_ES) &&
 414                     (p_pkt->i_pts > VLC_TS_INVALID) )
 415                 {
 416                     /* A hack to sync the A/V on PES files. */
 417                     msg_Dbg( p_demux, "force SCR: %"PRId64, p_pkt->i_pts );
 418                     es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_pkt->i_pts );
 419                 }
 420
 421                 if( (int64_t)p_pkt->i_pts > p_sys->i_current_pts )
 422                 {
 423                     p_sys->i_current_pts = (int64_t)p_pkt->i_pts;
 424                 }
 425
 426                 es_out_Send( p_demux->out, tk->es, p_pkt );
 427             }
 428             else
 429             {
 430                 block_Release( p_pkt );
 431             }
 432         }
 433         else
 434         {
 435             block_Release( p_pkt );
 436         }
 437         break;
 438     }
 439
 440     return 1;
 441 }
 442
 443 /*****************************************************************************
 444  * Control:
 445  *****************************************************************************/
 446 static int Control( demux_t *p_demux, int i_query, va_list args )
 447 {
 448     demux_sys_t *p_sys = p_demux->p_sys;
 449     double f, *pf;
 450     int64_t i64, *pi64;
 451
 452     switch( i_query )
 453     {
 454         case DEMUX_GET_POSITION:
 455             pf = (double*) va_arg( args, double* );
 456             i64 = stream_Size( p_demux->s );
 457             if( i64 > 0 )
 458             {
 459                 double current = stream_Tell( p_demux->s );
 460                 *pf = current / (double)i64;
 461             }
 462             else
 463             {
 464                 *pf = 0.0;
 465             }
 466             return VLC_SUCCESS;
 467
 468         case DEMUX_SET_POSITION:
 469             f = (double) va_arg( args, double );
 470             i64 = stream_Size( p_demux->s );
 471             p_sys->i_current_pts = 0;
 472
 473             return stream_Seek( p_demux->s, (int64_t)(i64 * f) );
 474
 475         case DEMUX_GET_TIME:
 476             pi64 = (int64_t*)va_arg( args, int64_t * );
 477             if( p_sys->i_time_track >= 0 && p_sys->i_current_pts > 0 )
 478             {
 479                 *pi64 = p_sys->i_current_pts - p_sys->tk[p_sys->i_time_track].i_first_pts;
 480                 return VLC_SUCCESS;
 481             }
 482             if( p_sys->i_mux_rate > 0 )
 483             {
 484                 *pi64 = (int64_t)1000000 * ( stream_Tell( p_demux->s ) / 50 ) /
 485                     p_sys->i_mux_rate;
 486                 return VLC_SUCCESS;
 487             }
 488             *pi64 = 0;
 489             return VLC_EGENERIC;
 490
 491         case DEMUX_GET_LENGTH:
 492             pi64 = (int64_t*)va_arg( args, int64_t * );
 493             if( p_sys->i_length > 0 )
 494             {
 495                 *pi64 = p_sys->i_length;
 496                 return VLC_SUCCESS;
 497             }
 498             else if( p_sys->i_mux_rate > 0 )
 499             {
 500                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) /
 501                     p_sys->i_mux_rate;
 502                 return VLC_SUCCESS;
 503             }
 504             *pi64 = 0;
 505             return VLC_EGENERIC;
 506
 507         case DEMUX_SET_TIME:
 508             i64 = (int64_t)va_arg( args, int64_t );
 509             if( p_sys->i_time_track >= 0 && p_sys->i_current_pts > 0 )
 510             {
 511                 int64_t i_now = p_sys->i_current_pts - p_sys->tk[p_sys->i_time_track].i_first_pts;
 512                 int64_t i_pos = stream_Tell( p_demux->s );
 513
 514                 if( !i_now )
 515                     return i64 ? VLC_EGENERIC : VLC_SUCCESS;
 516
 517                 p_sys->i_current_pts = 0;
 518                 i_pos *= (float)i64 / (float)i_now;
 519                 stream_Seek( p_demux->s, i_pos );
 520                 return VLC_SUCCESS;
 521             }
 522             return VLC_EGENERIC;
 523
 524         case DEMUX_GET_FPS:
 525         default:
 526             return VLC_EGENERIC;
 527     }
 528 }
 529
 530 /*****************************************************************************
 531  * Divers:
 532  *****************************************************************************/
 533
 534 /* PSResynch: resynch on a system startcode
 535  *  It doesn't skip more than 512 bytes
 536  *  -1 -> error, 0 -> not synch, 1 -> ok
 537  */
 538 static int ps_pkt_resynch( stream_t *s, uint32_t *pi_code )
 539 {
 540     const uint8_t *p_peek;
 541     int     i_peek;
 542     int     i_skip;
 543
 544     if( stream_Peek( s, &p_peek, 4 ) < 4 )
 545     {
 546         return -1;
 547     }
 548     if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 549         p_peek[3] >= 0xb9 )
 550     {
 551         *pi_code = 0x100 | p_peek[3];
 552         return 1;
 553     }
 554
 555     if( ( i_peek = stream_Peek( s, &p_peek, 512 ) ) < 4 )
 556     {
 557         return -1;
 558     }
 559     i_skip = 0;
 560
 561     for( ;; )
 562     {
 563         if( i_peek < 4 )
 564         {
 565             break;
 566         }
 567         if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 568             p_peek[3] >= 0xb9 )
 569         {
 570             *pi_code = 0x100 | p_peek[3];
 571             return stream_Read( s, NULL, i_skip ) == i_skip ? 1 : -1;
 572         }
 573
 574         p_peek++;
 575         i_peek--;
 576         i_skip++;
 577     }
 578     return stream_Read( s, NULL, i_skip ) == i_skip ? 0 : -1;
 579 }
 580
 581 static block_t *ps_pkt_read( stream_t *s, uint32_t i_code )
 582 {
 583     const uint8_t *p_peek;
 584     int      i_peek = stream_Peek( s, &p_peek, 14 );
 585     int      i_size;
 586     VLC_UNUSED(i_code);
 587
 588     /* Smallest valid packet */
 589     if( i_peek < 6 ) return NULL;
 590
 591     i_size = ps_pkt_size( p_peek, i_peek );
 592
 593     if( i_size < 0 || ( i_size <= 6 && p_peek[3] > 0xba ) )
 594     {
 595         /* Special case, search the next start code */
 596         i_size = 6;
 597         for( ;; )
 598         {
 599             i_peek = stream_Peek( s, &p_peek, i_size + 1024 );
 600             if( i_peek <= i_size + 4 )
 601             {
 602                 return NULL;
 603             }
 604             while( i_size <= i_peek - 4 )
 605             {
 606                 if( p_peek[i_size] == 0x00 && p_peek[i_size+1] == 0x00 &&
 607                     p_peek[i_size+2] == 0x01 && p_peek[i_size+3] >= 0xb9 )
 608                 {
 609                     return stream_Block( s, i_size );
 610                 }
 611                 i_size++;
 612             }
 613         }
 614     }
 615     else
 616     {
 617         /* Normal case */
 618         return stream_Block( s, i_size );
 619     }
 620
 621     return NULL;
 622 }