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