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 VLC authors and VideoLAN
   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 it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * 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, 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     int64_t     i_last_scr;
  86     int         i_mux_rate;
  87     int64_t     i_length;
  88     int         i_time_track;
  89     int64_t     i_current_pts;
  90
  91     int         i_aob_mlp_count;
  92
  93     bool  b_lost_sync;
  94     bool  b_have_pack;
  95     bool  b_seekable;
  96 };
  97
  98 static int Demux  ( demux_t *p_demux );
  99 static int Control( demux_t *p_demux, int i_query, va_list args );
 100
 101 static int      ps_pkt_resynch( stream_t *, uint32_t *pi_code );
 102 static block_t *ps_pkt_read   ( stream_t *, uint32_t i_code );
 103
 104 /*****************************************************************************
 105  * Open
 106  *****************************************************************************/
 107 static int OpenCommon( vlc_object_t *p_this, bool b_force )
 108 {
 109     demux_t     *p_demux = (demux_t*)p_this;
 110     demux_sys_t *p_sys;
 111
 112     const uint8_t *p_peek;
 113
 114     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
 115     {
 116         msg_Err( p_demux, "cannot peek" );
 117         return VLC_EGENERIC;
 118     }
 119
 120     if( memcmp( p_peek, "\x00\x00\x01", 3 ) || ( p_peek[3] < 0xb9 ) )
 121     {
 122         if( !b_force )
 123             return VLC_EGENERIC;
 124
 125         msg_Warn( p_demux, "this does not look like an MPEG PS stream, "
 126                   "continuing anyway" );
 127     }
 128
 129     /* Fill p_demux field */
 130     p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
 131     if( !p_sys ) return VLC_ENOMEM;
 132
 133     p_demux->pf_demux = Demux;
 134     p_demux->pf_control = Control;
 135
 136     /* Init p_sys */
 137     p_sys->i_mux_rate = 0;
 138     p_sys->i_scr      = -1;
 139     p_sys->i_last_scr = -1;
 140     p_sys->i_length   = -1;
 141     p_sys->i_current_pts = (mtime_t) 0;
 142     p_sys->i_time_track = -1;
 143     p_sys->i_aob_mlp_count = 0;
 144
 145     p_sys->b_lost_sync = false;
 146     p_sys->b_have_pack = false;
 147     p_sys->b_seekable  = false;
 148
 149     stream_Control( p_demux->s, STREAM_CAN_SEEK, &p_sys->b_seekable );
 150
 151     ps_psm_init( &p_sys->psm );
 152     ps_track_init( p_sys->tk );
 153
 154     /* TODO prescanning of ES */
 155
 156     return VLC_SUCCESS;
 157 }
 158
 159 static int OpenForce( vlc_object_t *p_this )
 160 {
 161     return OpenCommon( p_this, true );
 162 }
 163
 164 static int Open( vlc_object_t *p_this )
 165 {
 166     return OpenCommon( p_this, ((demux_t *)p_this)->b_force );
 167 }
 168
 169 /*****************************************************************************
 170  * Close
 171  *****************************************************************************/
 172 static void Close( vlc_object_t *p_this )
 173 {
 174     demux_t     *p_demux = (demux_t*)p_this;
 175     demux_sys_t *p_sys = p_demux->p_sys;
 176     int i;
 177
 178     for( i = 0; i < PS_TK_COUNT; i++ )
 179     {
 180         ps_track_t *tk = &p_sys->tk[i];
 181         if( tk->b_seen )
 182         {
 183             es_format_Clean( &tk->fmt );
 184             if( tk->es ) es_out_Del( p_demux->out, tk->es );
 185         }
 186     }
 187
 188     ps_psm_destroy( &p_sys->psm );
 189
 190     free( p_sys );
 191 }
 192
 193 static int Demux2( demux_t *p_demux, bool b_end )
 194 {
 195     demux_sys_t *p_sys = p_demux->p_sys;
 196     int i_ret, i_id;
 197     uint32_t i_code;
 198     block_t *p_pkt;
 199
 200     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
 201     if( i_ret < 0 )
 202     {
 203         return 0;
 204     }
 205     else if( i_ret == 0 )
 206     {
 207         if( !p_sys->b_lost_sync )
 208             msg_Warn( p_demux, "garbage at input, trying to resync..." );
 209
 210         p_sys->b_lost_sync = true;
 211         return 1;
 212     }
 213
 214     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
 215     p_sys->b_lost_sync = false;
 216
 217     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
 218     {
 219         return 0;
 220     }
 221     if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
 222     {
 223         ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
 224         if( !ps_pkt_parse_pes( p_pkt, tk->i_skip ) && p_pkt->i_pts > VLC_TS_INVALID )
 225         {
 226             if( b_end && p_pkt->i_pts > tk->i_last_pts )
 227             {
 228                 tk->i_last_pts = p_pkt->i_pts;
 229             }
 230             else if ( tk->i_first_pts == -1 )
 231             {
 232                 tk->i_first_pts = p_pkt->i_pts;
 233             }
 234         }
 235     }
 236     block_Release( p_pkt );
 237     return 1;
 238 }
 239
 240 static void FindLength( demux_t *p_demux )
 241 {
 242     demux_sys_t *p_sys = p_demux->p_sys;
 243     int64_t i_current_pos = -1, i_size = 0, i_end = 0;
 244
 245     if( !var_CreateGetBool( p_demux, "ps-trust-timestamps" ) )
 246         return;
 247
 248     if( p_sys->i_length == -1 ) /* First time */
 249     {
 250         p_sys->i_length = 0;
 251         /* Check beginning */
 252         int i = 0;
 253         i_current_pos = stream_Tell( p_demux->s );
 254         while( i < 40 && Demux2( p_demux, false ) > 0 ) i++;
 255
 256         /* Check end */
 257         i_size = stream_Size( p_demux->s );
 258         i_end = VLC_CLIP( i_size, 0, 200000 );
 259         stream_Seek( p_demux->s, i_size - i_end );
 260
 261         i = 0;
 262         while( i < 400 && Demux2( p_demux, true ) > 0 ) i++;
 263         if( i_current_pos >= 0 ) stream_Seek( p_demux->s, i_current_pos );
 264     }
 265
 266     /* Find the longest track */
 267     for( int i = 0; i < PS_TK_COUNT; i++ )
 268     {
 269         ps_track_t *tk = &p_sys->tk[i];
 270         if( tk->i_last_pts > 0 &&
 271             tk->i_last_pts > tk->i_first_pts )
 272         {
 273             int64_t i_length = (int64_t)tk->i_last_pts - tk->i_first_pts;
 274             if( i_length > p_sys->i_length )
 275             {
 276                 p_sys->i_length = i_length;
 277                 p_sys->i_time_track = i;
 278                 msg_Dbg( p_demux, "we found a length of: %"PRId64 "s", p_sys->i_length / CLOCK_FREQ );
 279             }
 280         }
 281     }
 282 }
 283
 284 /*****************************************************************************
 285  * Demux:
 286  *****************************************************************************/
 287 static int Demux( demux_t *p_demux )
 288 {
 289     demux_sys_t *p_sys = p_demux->p_sys;
 290     int i_ret, i_id, i_mux_rate;
 291     uint32_t i_code;
 292     block_t *p_pkt;
 293
 294     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
 295     if( i_ret < 0 )
 296     {
 297         return 0;
 298     }
 299     else if( i_ret == 0 )
 300     {
 301         if( !p_sys->b_lost_sync )
 302             msg_Warn( p_demux, "garbage at input, trying to resync..." );
 303
 304         p_sys->b_lost_sync = true;
 305         return 1;
 306     }
 307
 308     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
 309     p_sys->b_lost_sync = false;
 310
 311     if( p_sys->i_length < 0 && p_sys->b_seekable )
 312         FindLength( p_demux );
 313
 314     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
 315     {
 316         return 0;
 317     }
 318
 319     switch( i_code )
 320     {
 321     case 0x1b9:
 322         block_Release( p_pkt );
 323         break;
 324
 325     case 0x1ba:
 326         if( !ps_pkt_parse_pack( p_pkt, &p_sys->i_scr, &i_mux_rate ) )
 327         {
 328             p_sys->i_last_scr = p_sys->i_scr;
 329             if( !p_sys->b_have_pack ) p_sys->b_have_pack = true;
 330             /* done later on to work around bad vcd/svcd streams */
 331             /* es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr ); */
 332             if( i_mux_rate > 0 ) p_sys->i_mux_rate = i_mux_rate;
 333         }
 334         block_Release( p_pkt );
 335         break;
 336
 337     case 0x1bb:
 338         if( !ps_pkt_parse_system( p_pkt, &p_sys->psm, p_sys->tk ) )
 339         {
 340             int i;
 341             for( i = 0; i < PS_TK_COUNT; i++ )
 342             {
 343                 ps_track_t *tk = &p_sys->tk[i];
 344
 345                 if( tk->b_seen && !tk->es && tk->fmt.i_cat != UNKNOWN_ES )
 346                 {
 347                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 348                 }
 349             }
 350         }
 351         block_Release( p_pkt );
 352         break;
 353
 354     case 0x1bc:
 355         if( p_sys->psm.i_version == 0xFFFF )
 356             msg_Dbg( p_demux, "contains a PSM");
 357
 358         ps_psm_fill( &p_sys->psm, p_pkt, p_sys->tk, p_demux->out );
 359         block_Release( p_pkt );
 360         break;
 361
 362     default:
 363         if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
 364         {
 365             /* Small heuristic to improve MLP detection from AOB */
 366             if( i_id == 0xa001 &&
 367                 p_sys->i_aob_mlp_count < 500 )
 368             {
 369                 p_sys->i_aob_mlp_count++;
 370             }
 371             else if( i_id == 0xbda1 &&
 372                      p_sys->i_aob_mlp_count > 0 )
 373             {
 374                 p_sys->i_aob_mlp_count--;
 375                 i_id = 0xa001;
 376             }
 377
 378             bool b_new = false;
 379             ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
 380
 381             if( !tk->b_seen )
 382             {
 383                 if( !ps_track_fill( tk, &p_sys->psm, i_id, p_pkt ) )
 384                 {
 385                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 386                     b_new = true;
 387                 }
 388                 else
 389                 {
 390                     msg_Dbg( p_demux, "es id=0x%x format unknown", i_id );
 391                 }
 392                 tk->b_seen = true;
 393             }
 394
 395             /* The popular VCD/SVCD subtitling WinSubMux does not
 396              * renumber the SCRs when merging subtitles into the PES */
 397             if( tk->b_seen &&
 398                 ( tk->fmt.i_codec == VLC_CODEC_OGT ||
 399                   tk->fmt.i_codec == VLC_CODEC_CVD ) )
 400             {
 401                 p_sys->i_scr = -1;
 402                 p_sys->i_last_scr = -1;
 403             }
 404
 405             if( p_sys->i_scr >= 0 )
 406                 es_out_Control( p_demux->out, ES_OUT_SET_PCR, VLC_TS_0 + p_sys->i_scr );
 407
 408             p_sys->i_scr = -1;
 409
 410             if( tk->b_seen && tk->es &&
 411                 !ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
 412             {
 413                 if( !b_new && !p_sys->b_have_pack &&
 414                     (tk->fmt.i_cat == AUDIO_ES) &&
 415                     (p_pkt->i_pts > VLC_TS_INVALID) )
 416                 {
 417                     /* A hack to sync the A/V on PES files. */
 418                     msg_Dbg( p_demux, "force SCR: %"PRId64, p_pkt->i_pts );
 419                     es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_pkt->i_pts );
 420                 }
 421                 if( tk->fmt.i_codec == VLC_CODEC_TELETEXT &&
 422                     p_pkt->i_pts <= VLC_TS_INVALID && p_sys->i_last_scr >= 0 )
 423                 {
 424                     /* Teletext may have missing PTS (ETSI EN 300 472 Annexe A)
 425                      * In this case use the last SCR + 40ms */
 426                     p_pkt->i_pts = VLC_TS_0 + p_sys->i_last_scr + 40000;
 427                 }
 428
 429                 if( (int64_t)p_pkt->i_pts > p_sys->i_current_pts )
 430                 {
 431                     p_sys->i_current_pts = (int64_t)p_pkt->i_pts;
 432                 }
 433
 434                 es_out_Send( p_demux->out, tk->es, p_pkt );
 435             }
 436             else
 437             {
 438                 block_Release( p_pkt );
 439             }
 440         }
 441         else
 442         {
 443             block_Release( p_pkt );
 444         }
 445         break;
 446     }
 447
 448     demux_UpdateTitleFromStream( p_demux );
 449     return 1;
 450 }
 451
 452 /*****************************************************************************
 453  * Control:
 454  *****************************************************************************/
 455 static int Control( demux_t *p_demux, int i_query, va_list args )
 456 {
 457     demux_sys_t *p_sys = p_demux->p_sys;
 458     double f, *pf;
 459     int64_t i64, *pi64;
 460
 461     switch( i_query )
 462     {
 463         case DEMUX_GET_POSITION:
 464             pf = (double*) va_arg( args, double* );
 465             i64 = stream_Size( p_demux->s );
 466             if( i64 > 0 )
 467             {
 468                 double current = stream_Tell( p_demux->s );
 469                 *pf = current / (double)i64;
 470             }
 471             else
 472             {
 473                 *pf = 0.0;
 474             }
 475             return VLC_SUCCESS;
 476
 477         case DEMUX_SET_POSITION:
 478             f = (double) va_arg( args, double );
 479             i64 = stream_Size( p_demux->s );
 480             p_sys->i_current_pts = 0;
 481             p_sys->i_last_scr = -1;
 482
 483             return stream_Seek( p_demux->s, (int64_t)(i64 * f) );
 484
 485         case DEMUX_GET_TIME:
 486             pi64 = (int64_t*)va_arg( args, int64_t * );
 487             if( p_sys->i_time_track >= 0 && p_sys->i_current_pts > 0 )
 488             {
 489                 *pi64 = p_sys->i_current_pts - p_sys->tk[p_sys->i_time_track].i_first_pts;
 490                 return VLC_SUCCESS;
 491             }
 492             if( p_sys->i_mux_rate > 0 )
 493             {
 494                 *pi64 = (int64_t)1000000 * ( stream_Tell( p_demux->s ) / 50 ) /
 495                     p_sys->i_mux_rate;
 496                 return VLC_SUCCESS;
 497             }
 498             *pi64 = 0;
 499             return VLC_EGENERIC;
 500
 501         case DEMUX_GET_LENGTH:
 502             pi64 = (int64_t*)va_arg( args, int64_t * );
 503             if( p_sys->i_length > 0 )
 504             {
 505                 *pi64 = p_sys->i_length;
 506                 return VLC_SUCCESS;
 507             }
 508             else if( p_sys->i_mux_rate > 0 )
 509             {
 510                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) /
 511                     p_sys->i_mux_rate;
 512                 return VLC_SUCCESS;
 513             }
 514             *pi64 = 0;
 515             return VLC_EGENERIC;
 516
 517         case DEMUX_SET_TIME:
 518             i64 = (int64_t)va_arg( args, int64_t );
 519             if( p_sys->i_time_track >= 0 && p_sys->i_current_pts > 0 )
 520             {
 521                 int64_t i_now = p_sys->i_current_pts - p_sys->tk[p_sys->i_time_track].i_first_pts;
 522                 int64_t i_pos = stream_Tell( p_demux->s );
 523
 524                 if( !i_now )
 525                     return i64 ? VLC_EGENERIC : VLC_SUCCESS;
 526
 527                 p_sys->i_current_pts = 0;
 528                 p_sys->i_last_scr = -1;
 529                 i_pos *= (float)i64 / (float)i_now;
 530                 stream_Seek( p_demux->s, i_pos );
 531                 return VLC_SUCCESS;
 532             }
 533             return VLC_EGENERIC;
 534
 535         case DEMUX_GET_TITLE_INFO:
 536         {
 537             struct input_title_t ***v = va_arg( args, struct input_title_t*** );
 538             int *c = va_arg( args, int * );
 539
 540             *va_arg( args, int* ) = 0; /* Title offset */
 541             *va_arg( args, int* ) = 0; /* Chapter offset */
 542             return stream_Control( p_demux->s, STREAM_GET_TITLE_INFO, v, c );
 543         }
 544
 545         case DEMUX_SET_TITLE:
 546             return stream_vaControl( p_demux->s, STREAM_SET_TITLE, args );
 547
 548         case DEMUX_SET_SEEKPOINT:
 549             return stream_vaControl( p_demux->s, STREAM_SET_SEEKPOINT, args );
 550
 551         case DEMUX_GET_META:
 552             return stream_vaControl( p_demux->s, STREAM_GET_META, args );
 553
 554         case DEMUX_GET_FPS:
 555         default:
 556             return VLC_EGENERIC;
 557     }
 558 }
 559
 560 /*****************************************************************************
 561  * Divers:
 562  *****************************************************************************/
 563
 564 /* PSResynch: resynch on a system startcode
 565  *  It doesn't skip more than 512 bytes
 566  *  -1 -> error, 0 -> not synch, 1 -> ok
 567  */
 568 static int ps_pkt_resynch( stream_t *s, uint32_t *pi_code )
 569 {
 570     const uint8_t *p_peek;
 571     int     i_peek;
 572     int     i_skip;
 573
 574     if( stream_Peek( s, &p_peek, 4 ) < 4 )
 575     {
 576         return -1;
 577     }
 578     if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 579         p_peek[3] >= 0xb9 )
 580     {
 581         *pi_code = 0x100 | p_peek[3];
 582         return 1;
 583     }
 584
 585     if( ( i_peek = stream_Peek( s, &p_peek, 512 ) ) < 4 )
 586     {
 587         return -1;
 588     }
 589     i_skip = 0;
 590
 591     for( ;; )
 592     {
 593         if( i_peek < 4 )
 594         {
 595             break;
 596         }
 597         if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 598             p_peek[3] >= 0xb9 )
 599         {
 600             *pi_code = 0x100 | p_peek[3];
 601             return stream_Read( s, NULL, i_skip ) == i_skip ? 1 : -1;
 602         }
 603
 604         p_peek++;
 605         i_peek--;
 606         i_skip++;
 607     }
 608     return stream_Read( s, NULL, i_skip ) == i_skip ? 0 : -1;
 609 }
 610
 611 static block_t *ps_pkt_read( stream_t *s, uint32_t i_code )
 612 {
 613     const uint8_t *p_peek;
 614     int i_peek = stream_Peek( s, &p_peek, 14 );
 615     if( i_peek < 4 )
 616         return NULL;
 617
 618     int i_size = ps_pkt_size( p_peek, i_peek );
 619     if( i_size <= 6 && p_peek[3] > 0xba )
 620     {
 621         /* Special case, search the next start code */
 622         i_size = 6;
 623         for( ;; )
 624         {
 625             i_peek = stream_Peek( s, &p_peek, i_size + 1024 );
 626             if( i_peek <= i_size + 4 )
 627             {
 628                 return NULL;
 629             }
 630             while( i_size <= i_peek - 4 )
 631             {
 632                 if( p_peek[i_size] == 0x00 && p_peek[i_size+1] == 0x00 &&
 633                     p_peek[i_size+2] == 0x01 && p_peek[i_size+3] >= 0xb9 )
 634                 {
 635                     return stream_Block( s, i_size );
 636                 }
 637                 i_size++;
 638             }
 639         }
 640     }
 641     else
 642     {
 643         /* Normal case */
 644         return stream_Block( s, i_size );
 645     }
 646
 647     VLC_UNUSED(i_code);
 648     return NULL;
 649 }