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 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., 59 Temple Place - Suite 330, Boston, MA  02111, 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 /*****************************************************************************
  40  * Module descriptor
  41  *****************************************************************************/
  42 static int  Open   ( vlc_object_t * );
  43 static int  OpenAlt( vlc_object_t * );
  44 static void Close  ( vlc_object_t * );
  45
  46 vlc_module_begin();
  47     set_description( _("PS demuxer") );
  48     set_category( CAT_INPUT );
  49     set_subcategory( SUBCAT_INPUT_DEMUX );
  50     set_capability( "demux2", 1 );
  51     set_callbacks( Open, Close );
  52     add_shortcut( "ps" );
  53
  54     add_submodule();
  55     set_description( _("PS demuxer") );
  56     set_capability( "demux2", 9 );
  57     set_callbacks( OpenAlt, Close );
  58 vlc_module_end();
  59
  60 /*****************************************************************************
  61  * Local prototypes
  62  *****************************************************************************/
  63
  64 struct demux_sys_t
  65 {
  66     ps_psm_t    psm;
  67     ps_track_t  tk[PS_TK_COUNT];
  68
  69     int64_t     i_scr;
  70     int         i_mux_rate;
  71
  72     vlc_bool_t  b_lost_sync;
  73 };
  74
  75 static int Demux  ( demux_t *p_demux );
  76 static int Control( demux_t *p_demux, int i_query, va_list args );
  77
  78 static int      ps_pkt_resynch( stream_t *, uint32_t *pi_code );
  79 static block_t *ps_pkt_read   ( stream_t *, uint32_t i_code );
  80
  81 /*****************************************************************************
  82  * Open
  83  *****************************************************************************/
  84 static int Open( vlc_object_t *p_this )
  85 {
  86     demux_t     *p_demux = (demux_t*)p_this;
  87     demux_sys_t *p_sys;
  88
  89     uint8_t     *p_peek;
  90
  91     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
  92     {
  93         msg_Err( p_demux, "cannot peek" );
  94         return VLC_EGENERIC;
  95     }
  96
  97     if( p_peek[0] != 0 || p_peek[1] != 0 ||
  98         p_peek[2] != 1 || p_peek[3] < 0xb9 )
  99     {
 100         msg_Warn( p_demux, "this does not look like an MPEG PS stream, "
 101                   "continuing anyway" );
 102     }
 103
 104     /* Fill p_demux field */
 105     p_demux->pf_demux = Demux;
 106     p_demux->pf_control = Control;
 107     p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
 108
 109     /* Init p_sys */
 110     p_sys->i_mux_rate = 0;
 111     p_sys->i_scr      = -1;
 112     p_sys->b_lost_sync = VLC_FALSE;
 113
 114     ps_psm_init( &p_sys->psm );
 115     ps_track_init( p_sys->tk );
 116
 117     /* TODO prescanning of ES */
 118
 119     return VLC_SUCCESS;
 120 }
 121
 122 static int OpenAlt( vlc_object_t *p_this )
 123 {
 124     demux_t *p_demux = (demux_t*)p_this;
 125     uint8_t *p_peek;
 126
 127     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
 128     {
 129         msg_Err( p_demux, "cannot peek" );
 130         return VLC_EGENERIC;
 131     }
 132
 133     if( p_peek[0] != 0 || p_peek[1] != 0 ||
 134         p_peek[2] != 1 || p_peek[3] < 0xb9 )
 135     {
 136         if( !p_demux->b_force ) return VLC_EGENERIC;
 137     }
 138
 139     return Open( p_this );
 140 }
 141
 142 /*****************************************************************************
 143  * Close
 144  *****************************************************************************/
 145 static void Close( vlc_object_t *p_this )
 146 {
 147     demux_t     *p_demux = (demux_t*)p_this;
 148     demux_sys_t *p_sys = p_demux->p_sys;
 149     int i;
 150
 151     for( i = 0; i < PS_TK_COUNT; i++ )
 152     {
 153         ps_track_t *tk = &p_sys->tk[i];
 154         if( tk->b_seen )
 155         {
 156             es_format_Clean( &tk->fmt );
 157             if( tk->es ) es_out_Del( p_demux->out, tk->es );
 158         }
 159     }
 160
 161     ps_psm_destroy( &p_sys->psm );
 162
 163     free( p_sys );
 164 }
 165
 166 /*****************************************************************************
 167  * Demux:
 168  *****************************************************************************/
 169 static int Demux( demux_t *p_demux )
 170 {
 171     demux_sys_t *p_sys = p_demux->p_sys;
 172     int i_ret, i_id, i_mux_rate;
 173     uint32_t i_code;
 174     block_t *p_pkt;
 175
 176     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
 177     if( i_ret < 0 )
 178     {
 179         return 0;
 180     }
 181     else if( i_ret == 0 )
 182     {
 183         if( !p_sys->b_lost_sync )
 184             msg_Warn( p_demux, "garbage at input, trying to resync..." );
 185
 186         p_sys->b_lost_sync = VLC_TRUE;
 187         return 1;
 188     }
 189
 190     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
 191     p_sys->b_lost_sync = VLC_FALSE;
 192
 193     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
 194     {
 195         return 0;
 196     }
 197
 198     switch( i_code )
 199     {
 200     case 0x1b9:
 201         block_Release( p_pkt );
 202         break;
 203
 204     case 0x1ba:
 205         if( !ps_pkt_parse_pack( p_pkt, &p_sys->i_scr, &i_mux_rate ) )
 206         {
 207             /* done later on to work around bad vcd/svcd streams */
 208             /* es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr ); */
 209             if( i_mux_rate > 0 ) p_sys->i_mux_rate = i_mux_rate;
 210         }
 211         block_Release( p_pkt );
 212         break;
 213
 214     case 0x1bb:
 215         if( !ps_pkt_parse_system( p_pkt, &p_sys->psm, p_sys->tk ) )
 216         {
 217             int i;
 218             for( i = 0; i < PS_TK_COUNT; i++ )
 219             {
 220                 ps_track_t *tk = &p_sys->tk[i];
 221
 222                 if( tk->b_seen && !tk->es && tk->fmt.i_cat != UNKNOWN_ES )
 223                 {
 224                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 225                 }
 226             }
 227         }
 228         block_Release( p_pkt );
 229         break;
 230
 231     case 0x1bc:
 232         if( p_sys->psm.i_version == 0xFFFF )
 233             msg_Dbg( p_demux, "contains a PSM");
 234
 235         ps_psm_fill( &p_sys->psm, p_pkt, p_sys->tk, p_demux->out );
 236         block_Release( p_pkt );
 237         break;
 238
 239     default:
 240         if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
 241         {
 242             ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
 243
 244             if( !tk->b_seen )
 245             {
 246                 if( !ps_track_fill( tk, &p_sys->psm, i_id ) )
 247                 {
 248                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 249                 }
 250                 else
 251                 {
 252                     msg_Dbg( p_demux, "es id=0x%x format unknown", i_id );
 253                 }
 254                 tk->b_seen = VLC_TRUE;
 255             }
 256
 257             /* The popular VCD/SVCD subtitling WinSubMux does not
 258              * renumber the SCRs when merging subtitles into the PES */
 259             if( tk->b_seen &&
 260                 ( tk->fmt.i_codec == VLC_FOURCC('o','g','t',' ') ||
 261                   tk->fmt.i_codec == VLC_FOURCC('c','v','d',' ') ) )
 262             {
 263                 p_sys->i_scr = -1;
 264             }
 265
 266             if( p_sys->i_scr > 0 )
 267                 es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr );
 268
 269             p_sys->i_scr = -1;
 270
 271             if( tk->b_seen && tk->es &&
 272                 !ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
 273             {
 274                 es_out_Send( p_demux->out, tk->es, p_pkt );
 275             }
 276             else
 277             {
 278                 block_Release( p_pkt );
 279             }
 280         }
 281         else
 282         {
 283             block_Release( p_pkt );
 284         }
 285         break;
 286     }
 287
 288     return 1;
 289 }
 290
 291 /*****************************************************************************
 292  * Control:
 293  *****************************************************************************/
 294 static int Control( demux_t *p_demux, int i_query, va_list args )
 295 {
 296     demux_sys_t *p_sys = p_demux->p_sys;
 297     double f, *pf;
 298     int64_t i64, *pi64;
 299
 300     switch( i_query )
 301     {
 302         case DEMUX_GET_POSITION:
 303             pf = (double*) va_arg( args, double* );
 304             i64 = stream_Size( p_demux->s );
 305             if( i64 > 0 )
 306             {
 307                 *pf = (double)stream_Tell( p_demux->s ) / (double)i64;
 308             }
 309             else
 310             {
 311                 *pf = 0.0;
 312             }
 313             return VLC_SUCCESS;
 314
 315         case DEMUX_SET_POSITION:
 316             f = (double) va_arg( args, double );
 317             i64 = stream_Size( p_demux->s );
 318
 319             es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
 320
 321             return stream_Seek( p_demux->s, (int64_t)(i64 * f) );
 322
 323         case DEMUX_GET_TIME:
 324             pi64 = (int64_t*)va_arg( args, int64_t * );
 325             if( p_sys->i_mux_rate > 0 )
 326             {
 327                 *pi64 = (int64_t)1000000 * ( stream_Tell( p_demux->s ) / 50 ) /
 328                     p_sys->i_mux_rate;
 329                 return VLC_SUCCESS;
 330             }
 331             *pi64 = 0;
 332             return VLC_EGENERIC;
 333
 334         case DEMUX_GET_LENGTH:
 335             pi64 = (int64_t*)va_arg( args, int64_t * );
 336             if( p_sys->i_mux_rate > 0 )
 337             {
 338                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) /
 339                     p_sys->i_mux_rate;
 340                 return VLC_SUCCESS;
 341             }
 342             *pi64 = 0;
 343             return VLC_EGENERIC;
 344
 345         case DEMUX_SET_TIME:
 346         case DEMUX_GET_FPS:
 347         default:
 348             return VLC_EGENERIC;
 349     }
 350 }
 351
 352 /*****************************************************************************
 353  * Divers:
 354  *****************************************************************************/
 355
 356 /* PSResynch: resynch on a system starcode
 357  *  It doesn't skip more than 512 bytes
 358  *  -1 -> error, 0 -> not synch, 1 -> ok
 359  */
 360 static int ps_pkt_resynch( stream_t *s, uint32_t *pi_code )
 361 {
 362     uint8_t *p_peek;
 363     int     i_peek;
 364     int     i_skip;
 365
 366     if( stream_Peek( s, &p_peek, 4 ) < 4 )
 367     {
 368         return -1;
 369     }
 370     if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 371         p_peek[3] >= 0xb9 )
 372     {
 373         *pi_code = 0x100 | p_peek[3];
 374         return 1;
 375     }
 376
 377     if( ( i_peek = stream_Peek( s, &p_peek, 512 ) ) < 4 )
 378     {
 379         return -1;
 380     }
 381     i_skip = 0;
 382
 383     for( ;; )
 384     {
 385         if( i_peek < 4 )
 386         {
 387             break;
 388         }
 389         if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 390             p_peek[3] >= 0xb9 )
 391         {
 392             *pi_code = 0x100 | p_peek[3];
 393             return stream_Read( s, NULL, i_skip ) == i_skip ? 1 : -1;
 394         }
 395
 396         p_peek++;
 397         i_peek--;
 398         i_skip++;
 399     }
 400     return stream_Read( s, NULL, i_skip ) == i_skip ? 0 : -1;
 401 }
 402
 403 static block_t *ps_pkt_read( stream_t *s, uint32_t i_code )
 404 {
 405     uint8_t *p_peek;
 406     int      i_peek = stream_Peek( s, &p_peek, 14 );
 407     int      i_size = ps_pkt_size( p_peek, i_peek );
 408
 409     if( i_size <= 6 && p_peek[3] > 0xba )
 410     {
 411         /* Special case, search the next start code */
 412         i_size = 6;
 413         for( ;; )
 414         {
 415             i_peek = stream_Peek( s, &p_peek, i_size + 1024 );
 416             if( i_peek <= i_size + 4 )
 417             {
 418                 return NULL;
 419             }
 420             while( i_size <= i_peek - 4 )
 421             {
 422                 if( p_peek[i_size] == 0x00 && p_peek[i_size+1] == 0x00 &&
 423                     p_peek[i_size+2] == 0x01 && p_peek[i_size+3] >= 0xb9 )
 424                 {
 425                     return stream_Block( s, i_size );
 426                 }
 427                 i_size++;
 428             }
 429         }
 430     }
 431     else
 432     {
 433         /* Normal case */
 434         return stream_Block( s, i_size );
 435     }
 436
 437     return NULL;
 438 }