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., 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 /*****************************************************************************
  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     vlc_bool_t  b_have_pack;
  74 };
  75
  76 static int Demux  ( demux_t *p_demux );
  77 static int Control( demux_t *p_demux, int i_query, va_list args );
  78
  79 static int      ps_pkt_resynch( stream_t *, uint32_t *pi_code );
  80 static block_t *ps_pkt_read   ( stream_t *, uint32_t i_code );
  81
  82 /*****************************************************************************
  83  * Open
  84  *****************************************************************************/
  85 static int Open( vlc_object_t *p_this )
  86 {
  87     demux_t     *p_demux = (demux_t*)p_this;
  88     demux_sys_t *p_sys;
  89
  90     uint8_t     *p_peek;
  91
  92     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
  93     {
  94         msg_Err( p_demux, "cannot peek" );
  95         return VLC_EGENERIC;
  96     }
  97
  98     if( p_peek[0] != 0 || p_peek[1] != 0 ||
  99         p_peek[2] != 1 || p_peek[3] < 0xb9 )
 100     {
 101         msg_Warn( p_demux, "this does not look like an MPEG PS stream, "
 102                   "continuing anyway" );
 103     }
 104
 105     /* Fill p_demux field */
 106     p_demux->pf_demux = Demux;
 107     p_demux->pf_control = Control;
 108     p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
 109
 110     /* Init p_sys */
 111     p_sys->i_mux_rate = 0;
 112     p_sys->i_scr      = -1;
 113     p_sys->b_lost_sync = VLC_FALSE;
 114     p_sys->b_have_pack = VLC_FALSE;
 115
 116     ps_psm_init( &p_sys->psm );
 117     ps_track_init( p_sys->tk );
 118
 119     /* TODO prescanning of ES */
 120
 121     return VLC_SUCCESS;
 122 }
 123
 124 static int OpenAlt( vlc_object_t *p_this )
 125 {
 126     demux_t *p_demux = (demux_t*)p_this;
 127     uint8_t *p_peek;
 128
 129     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
 130     {
 131         msg_Err( p_demux, "cannot peek" );
 132         return VLC_EGENERIC;
 133     }
 134
 135     if( p_peek[0] != 0 || p_peek[1] != 0 ||
 136         p_peek[2] != 1 || p_peek[3] < 0xb9 )
 137     {
 138         if( !p_demux->b_force ) return VLC_EGENERIC;
 139     }
 140
 141     return Open( p_this );
 142 }
 143
 144 /*****************************************************************************
 145  * Close
 146  *****************************************************************************/
 147 static void Close( vlc_object_t *p_this )
 148 {
 149     demux_t     *p_demux = (demux_t*)p_this;
 150     demux_sys_t *p_sys = p_demux->p_sys;
 151     int i;
 152
 153     for( i = 0; i < PS_TK_COUNT; i++ )
 154     {
 155         ps_track_t *tk = &p_sys->tk[i];
 156         if( tk->b_seen )
 157         {
 158             es_format_Clean( &tk->fmt );
 159             if( tk->es ) es_out_Del( p_demux->out, tk->es );
 160         }
 161     }
 162
 163     ps_psm_destroy( &p_sys->psm );
 164
 165     free( p_sys );
 166 }
 167
 168 /*****************************************************************************
 169  * Demux:
 170  *****************************************************************************/
 171 static int Demux( demux_t *p_demux )
 172 {
 173     demux_sys_t *p_sys = p_demux->p_sys;
 174     int i_ret, i_id, i_mux_rate;
 175     uint32_t i_code;
 176     block_t *p_pkt;
 177
 178     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
 179     if( i_ret < 0 )
 180     {
 181         return 0;
 182     }
 183     else if( i_ret == 0 )
 184     {
 185         if( !p_sys->b_lost_sync )
 186             msg_Warn( p_demux, "garbage at input, trying to resync..." );
 187
 188         p_sys->b_lost_sync = VLC_TRUE;
 189         return 1;
 190     }
 191
 192     if( p_sys->b_lost_sync ) msg_Warn( p_demux, "found sync code" );
 193     p_sys->b_lost_sync = VLC_FALSE;
 194
 195     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
 196     {
 197         return 0;
 198     }
 199
 200     switch( i_code )
 201     {
 202     case 0x1b9:
 203         block_Release( p_pkt );
 204         break;
 205
 206     case 0x1ba:
 207         if( !ps_pkt_parse_pack( p_pkt, &p_sys->i_scr, &i_mux_rate ) )
 208         {
 209             if( !p_sys->b_have_pack ) p_sys->b_have_pack = VLC_TRUE;
 210             /* done later on to work around bad vcd/svcd streams */
 211             /* es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr ); */
 212             if( i_mux_rate > 0 ) p_sys->i_mux_rate = i_mux_rate;
 213         }
 214         block_Release( p_pkt );
 215         break;
 216
 217     case 0x1bb:
 218         if( !ps_pkt_parse_system( p_pkt, &p_sys->psm, p_sys->tk ) )
 219         {
 220             int i;
 221             for( i = 0; i < PS_TK_COUNT; i++ )
 222             {
 223                 ps_track_t *tk = &p_sys->tk[i];
 224
 225                 if( tk->b_seen && !tk->es && tk->fmt.i_cat != UNKNOWN_ES )
 226                 {
 227                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 228                 }
 229             }
 230         }
 231         block_Release( p_pkt );
 232         break;
 233
 234     case 0x1bc:
 235         if( p_sys->psm.i_version == 0xFFFF )
 236             msg_Dbg( p_demux, "contains a PSM");
 237
 238         ps_psm_fill( &p_sys->psm, p_pkt, p_sys->tk, p_demux->out );
 239         block_Release( p_pkt );
 240         break;
 241
 242     default:
 243         if( (i_id = ps_pkt_id( p_pkt )) >= 0xc0 )
 244         {
 245             vlc_bool_t b_new = VLC_FALSE;
 246             ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
 247
 248             if( !tk->b_seen )
 249             {
 250                 if( !ps_track_fill( tk, &p_sys->psm, i_id ) )
 251                 {
 252                     tk->es = es_out_Add( p_demux->out, &tk->fmt );
 253                     b_new = VLC_TRUE;
 254                 }
 255                 else
 256                 {
 257                     msg_Dbg( p_demux, "es id=0x%x format unknown", i_id );
 258                 }
 259                 tk->b_seen = VLC_TRUE;
 260             }
 261
 262             /* The popular VCD/SVCD subtitling WinSubMux does not
 263              * renumber the SCRs when merging subtitles into the PES */
 264             if( tk->b_seen &&
 265                 ( tk->fmt.i_codec == VLC_FOURCC('o','g','t',' ') ||
 266                   tk->fmt.i_codec == VLC_FOURCC('c','v','d',' ') ) )
 267             {
 268                 p_sys->i_scr = -1;
 269             }
 270
 271             if( p_sys->i_scr > 0 )
 272                 es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr );
 273
 274             p_sys->i_scr = -1;
 275
 276             if( tk->b_seen && tk->es &&
 277                 !ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
 278             {
 279                 if( !b_new && !p_sys->b_have_pack && tk->fmt.i_cat == AUDIO_ES && p_pkt->i_pts > 0 )
 280                 {
 281                     /* A hack to sync the A/V on PES files. */
 282                     msg_Dbg( p_demux, "force SCR: %lld", p_pkt->i_pts );
 283                     es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_pkt->i_pts );
 284                 }
 285
 286                 es_out_Send( p_demux->out, tk->es, p_pkt );
 287             }
 288             else
 289             {
 290                 block_Release( p_pkt );
 291             }
 292         }
 293         else
 294         {
 295             block_Release( p_pkt );
 296         }
 297         break;
 298     }
 299
 300     return 1;
 301 }
 302
 303 /*****************************************************************************
 304  * Control:
 305  *****************************************************************************/
 306 static int Control( demux_t *p_demux, int i_query, va_list args )
 307 {
 308     demux_sys_t *p_sys = p_demux->p_sys;
 309     double f, *pf;
 310     int64_t i64, *pi64;
 311
 312     switch( i_query )
 313     {
 314         case DEMUX_GET_POSITION:
 315             pf = (double*) va_arg( args, double* );
 316             i64 = stream_Size( p_demux->s );
 317             if( i64 > 0 )
 318             {
 319                 *pf = (double)stream_Tell( p_demux->s ) / (double)i64;
 320             }
 321             else
 322             {
 323                 *pf = 0.0;
 324             }
 325             return VLC_SUCCESS;
 326
 327         case DEMUX_SET_POSITION:
 328             f = (double) va_arg( args, double );
 329             i64 = stream_Size( p_demux->s );
 330
 331             es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
 332
 333             return stream_Seek( p_demux->s, (int64_t)(i64 * f) );
 334
 335         case DEMUX_GET_TIME:
 336             pi64 = (int64_t*)va_arg( args, int64_t * );
 337             if( p_sys->i_mux_rate > 0 )
 338             {
 339                 *pi64 = (int64_t)1000000 * ( stream_Tell( p_demux->s ) / 50 ) /
 340                     p_sys->i_mux_rate;
 341                 return VLC_SUCCESS;
 342             }
 343             *pi64 = 0;
 344             return VLC_EGENERIC;
 345
 346         case DEMUX_GET_LENGTH:
 347             pi64 = (int64_t*)va_arg( args, int64_t * );
 348             if( p_sys->i_mux_rate > 0 )
 349             {
 350                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) /
 351                     p_sys->i_mux_rate;
 352                 return VLC_SUCCESS;
 353             }
 354             *pi64 = 0;
 355             return VLC_EGENERIC;
 356
 357         case DEMUX_SET_TIME:
 358         case DEMUX_GET_FPS:
 359         default:
 360             return VLC_EGENERIC;
 361     }
 362 }
 363
 364 /*****************************************************************************
 365  * Divers:
 366  *****************************************************************************/
 367
 368 /* PSResynch: resynch on a system starcode
 369  *  It doesn't skip more than 512 bytes
 370  *  -1 -> error, 0 -> not synch, 1 -> ok
 371  */
 372 static int ps_pkt_resynch( stream_t *s, uint32_t *pi_code )
 373 {
 374     uint8_t *p_peek;
 375     int     i_peek;
 376     int     i_skip;
 377
 378     if( stream_Peek( s, &p_peek, 4 ) < 4 )
 379     {
 380         return -1;
 381     }
 382     if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 383         p_peek[3] >= 0xb9 )
 384     {
 385         *pi_code = 0x100 | p_peek[3];
 386         return 1;
 387     }
 388
 389     if( ( i_peek = stream_Peek( s, &p_peek, 512 ) ) < 4 )
 390     {
 391         return -1;
 392     }
 393     i_skip = 0;
 394
 395     for( ;; )
 396     {
 397         if( i_peek < 4 )
 398         {
 399             break;
 400         }
 401         if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 &&
 402             p_peek[3] >= 0xb9 )
 403         {
 404             *pi_code = 0x100 | p_peek[3];
 405             return stream_Read( s, NULL, i_skip ) == i_skip ? 1 : -1;
 406         }
 407
 408         p_peek++;
 409         i_peek--;
 410         i_skip++;
 411     }
 412     return stream_Read( s, NULL, i_skip ) == i_skip ? 0 : -1;
 413 }
 414
 415 static block_t *ps_pkt_read( stream_t *s, uint32_t i_code )
 416 {
 417     uint8_t *p_peek;
 418     int      i_peek = stream_Peek( s, &p_peek, 14 );
 419     int      i_size = ps_pkt_size( p_peek, i_peek );
 420
 421     if( i_size <= 6 && p_peek[3] > 0xba )
 422     {
 423         /* Special case, search the next start code */
 424         i_size = 6;
 425         for( ;; )
 426         {
 427             i_peek = stream_Peek( s, &p_peek, i_size + 1024 );
 428             if( i_peek <= i_size + 4 )
 429             {
 430                 return NULL;
 431             }
 432             while( i_size <= i_peek - 4 )
 433             {
 434                 if( p_peek[i_size] == 0x00 && p_peek[i_size+1] == 0x00 &&
 435                     p_peek[i_size+2] == 0x01 && p_peek[i_size+3] >= 0xb9 )
 436                 {
 437                     return stream_Block( s, i_size );
 438                 }
 439                 i_size++;
 440             }
 441         }
 442     }
 443     else
 444     {
 445         /* Normal case */
 446         return stream_Block( s, i_size );
 447     }
 448
 449     return NULL;
 450 }