modules/demux/nsv.c

   1 /*****************************************************************************
   2  * nsv.c: NullSoft Video demuxer.
   3  *****************************************************************************
   4  * Copyright (C) 2004-2007 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 /* TODO:
  37  *  - implement NSVf parsing (to get meta data)
  38  *  - implement missing Control (and in the right way)
  39  *  - ...
  40  */
  41
  42 /*****************************************************************************
  43  * Module descriptor
  44  *****************************************************************************/
  45 static int  Open    ( vlc_object_t * );
  46 static void Close  ( vlc_object_t * );
  47
  48 vlc_module_begin ()
  49     set_description( N_("NullSoft demuxer" ) )
  50     set_capability( "demux", 10 )
  51     set_category( CAT_INPUT )
  52     set_subcategory( SUBCAT_INPUT_DEMUX )
  53     set_callbacks( Open, Close )
  54     add_shortcut( "nsv" )
  55 vlc_module_end ()
  56
  57 /*****************************************************************************
  58  * Local prototypes
  59  *****************************************************************************/
  60
  61 typedef struct
  62 {
  63     es_format_t  fmt_audio;
  64     es_out_id_t *p_audio;
  65
  66     es_format_t  fmt_video;
  67     es_out_id_t *p_video;
  68
  69     es_format_t  fmt_sub;
  70     es_out_id_t  *p_sub;
  71
  72     int64_t     i_pcr;
  73     int64_t     i_time;
  74     int64_t     i_pcr_inc;
  75
  76     bool b_start_record;
  77 } demux_sys_t;
  78
  79 static int Demux  ( demux_t *p_demux );
  80 static int Control( demux_t *p_demux, int i_query, va_list args );
  81
  82 static int ReSynch( demux_t *p_demux );
  83
  84 static int ReadNSVf( demux_t *p_demux );
  85 static int ReadNSVs( demux_t *p_demux );
  86
  87 /*****************************************************************************
  88  * Open
  89  *****************************************************************************/
  90 static int Open( vlc_object_t *p_this )
  91 {
  92     demux_t     *p_demux = (demux_t*)p_this;
  93     demux_sys_t *p_sys;
  94
  95     const uint8_t *p_peek;
  96
  97     if( vlc_stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
  98         return VLC_EGENERIC;
  99
 100     if( memcmp( p_peek, "NSVf", 4 ) && memcmp( p_peek, "NSVs", 4 ) )
 101     {
 102        /* In case we had force this demuxer we try to resynch */
 103         if( !p_demux->obj.force || ReSynch( p_demux ) )
 104             return VLC_EGENERIC;
 105     }
 106
 107     p_sys = malloc( sizeof( demux_sys_t ) );
 108     if( unlikely(p_sys == NULL) )
 109         return VLC_ENOMEM;
 110
 111     /* Fill p_demux field */
 112     p_demux->p_sys = p_sys;
 113     p_demux->pf_demux = Demux;
 114     p_demux->pf_control = Control;
 115
 116     es_format_Init( &p_sys->fmt_audio, AUDIO_ES, 0 );
 117     p_sys->p_audio = NULL;
 118
 119     es_format_Init( &p_sys->fmt_video, VIDEO_ES, 0 );
 120     p_sys->p_video = NULL;
 121
 122     es_format_Init( &p_sys->fmt_sub, SPU_ES, 0 );
 123     p_sys->p_sub = NULL;
 124
 125     p_sys->i_pcr   = 0;
 126     p_sys->i_time  = 0;
 127     p_sys->i_pcr_inc = 0;
 128
 129     p_sys->b_start_record = false;
 130
 131     return VLC_SUCCESS;
 132 }
 133
 134 /*****************************************************************************
 135  * Close
 136  *****************************************************************************/
 137 static void Close( vlc_object_t *p_this )
 138 {
 139     demux_t     *p_demux = (demux_t*)p_this;
 140     demux_sys_t *p_sys = p_demux->p_sys;
 141
 142     free( p_sys );
 143 }
 144
 145
 146 /*****************************************************************************
 147  * Demux:
 148  *****************************************************************************/
 149 static int Demux( demux_t *p_demux )
 150 {
 151     demux_sys_t *p_sys = p_demux->p_sys;
 152
 153     uint8_t     header[5];
 154     const uint8_t *p_peek;
 155
 156     int         i_size;
 157     block_t     *p_frame;
 158
 159     for( ;; )
 160     {
 161         if( vlc_stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
 162         {
 163             msg_Warn( p_demux, "cannot peek" );
 164             return VLC_DEMUXER_EOF;
 165         }
 166
 167         if( !memcmp( p_peek, "NSVf", 4 ) )
 168         {
 169             if( ReadNSVf( p_demux ) )
 170                 return VLC_DEMUXER_EGENERIC;
 171         }
 172         else if( !memcmp( p_peek, "NSVs", 4 ) )
 173         {
 174             if( p_sys->b_start_record )
 175             {
 176                 /* Enable recording once synchronized */
 177                 vlc_stream_Control( p_demux->s, STREAM_SET_RECORD_STATE, true, "nsv" );
 178                 p_sys->b_start_record = false;
 179             }
 180
 181             if( ReadNSVs( p_demux ) )
 182                 return VLC_DEMUXER_EGENERIC;
 183             break;
 184         }
 185         else if( GetWLE( p_peek ) == 0xbeef )
 186         {
 187             /* Next frame of the current NSVs chunk */
 188             if( vlc_stream_Read( p_demux->s, NULL, 2 ) < 2 )
 189             {
 190                 msg_Warn( p_demux, "cannot read" );
 191                 return VLC_DEMUXER_EOF;
 192             }
 193             break;
 194         }
 195         else
 196         {
 197             msg_Err( p_demux, "invalid signature 0x%x (%4.4s)", GetDWLE( p_peek ), (const char*)p_peek );
 198             if( ReSynch( p_demux ) )
 199                 return VLC_DEMUXER_EGENERIC;
 200         }
 201     }
 202
 203     if( vlc_stream_Read( p_demux->s, header, 5 ) < 5 )
 204     {
 205         msg_Warn( p_demux, "cannot read" );
 206         return VLC_DEMUXER_EOF;
 207     }
 208
 209     /* Set PCR */
 210     es_out_SetPCR( p_demux->out, VLC_TICK_0 + p_sys->i_pcr );
 211
 212     /* Read video */
 213     i_size = ( header[0] >> 4 ) | ( header[1] << 4 ) | ( header[2] << 12 );
 214     if( i_size > 0 )
 215     {
 216         /* extra data ? */
 217         if( (header[0]&0x0f) != 0x0 )
 218         {
 219             uint8_t      aux[6];
 220             int          i_aux;
 221             vlc_fourcc_t fcc;
 222             if( vlc_stream_Read( p_demux->s, aux, 6 ) < 6 )
 223             {
 224                 msg_Warn( p_demux, "cannot read" );
 225                 return VLC_DEMUXER_EOF;
 226             }
 227             i_aux = GetWLE( aux );
 228             fcc   = VLC_FOURCC( aux[2], aux[3], aux[4], aux[5] );
 229
 230             msg_Dbg( p_demux, "Belekas: %d - size=%d fcc=%4.4s",
 231                      header[0]&0xf, i_aux, (char*)&fcc );
 232
 233             if( fcc == VLC_FOURCC( 'S', 'U', 'B', 'T' ) && i_aux > 2 )
 234             {
 235                 if( p_sys->p_sub == NULL )
 236                 {
 237                     p_sys->fmt_sub.i_codec = VLC_FOURCC( 's', 'u', 'b', 't' );
 238                     p_sys->p_sub = es_out_Add( p_demux->out, &p_sys->fmt_sub );
 239                     if( p_sys->p_sub )
 240                         es_out_Control( p_demux->out, ES_OUT_SET_ES, p_sys->p_sub );
 241                 }
 242                 if( vlc_stream_Read( p_demux->s, NULL, 2 ) < 2 )
 243                     return VLC_DEMUXER_EOF;
 244
 245                 if( ( p_frame = vlc_stream_Block( p_demux->s, i_aux - 2 ) ) )
 246                 {
 247                     uint8_t *p = p_frame->p_buffer;
 248
 249                     while( p < &p_frame->p_buffer[p_frame->i_buffer] && *p != 0 )
 250                     {
 251                         p++;
 252                     }
 253                     if( *p == 0 && p + 1 < &p_frame->p_buffer[p_frame->i_buffer] )
 254                     {
 255                         p_frame->i_buffer -= p + 1 - p_frame->p_buffer;
 256                         p_frame->p_buffer = p + 1;
 257                     }
 258
 259                     /* Skip the first part (it is the language name) */
 260                     p_frame->i_pts = VLC_TICK_0 + p_sys->i_pcr;
 261                     p_frame->i_dts = VLC_TICK_0 + p_sys->i_pcr + VLC_TICK_FROM_SEC(4);
 262
 263                     if( p_sys->p_sub )
 264                         es_out_Send( p_demux->out, p_sys->p_sub, p_frame );
 265                     else
 266                         block_Release( p_frame );
 267                 }
 268             }
 269             else
 270             {
 271                 /* We skip this extra data */
 272                 if( vlc_stream_Read( p_demux->s, NULL, i_aux ) < i_aux )
 273                 {
 274                     msg_Warn( p_demux, "cannot read" );
 275                     return VLC_DEMUXER_EOF;
 276                 }
 277             }
 278             i_size -= 6 + i_aux;
 279         }
 280
 281         /* msg_Dbg( p_demux, "frame video size=%d", i_size ); */
 282         if( i_size > 0 && ( p_frame = vlc_stream_Block( p_demux->s, i_size ) ) )
 283         {
 284             p_frame->i_dts = VLC_TICK_0 + p_sys->i_pcr;
 285
 286             if( p_sys->p_video )
 287                 es_out_Send( p_demux->out, p_sys->p_video, p_frame );
 288             else
 289             {
 290                 block_Release( p_frame );
 291                 msg_Dbg( p_demux, "ignoring unsupported video frame (size=%d)",
 292                          i_size );
 293             }
 294         }
 295     }
 296
 297     /* Read audio */
 298     i_size = header[3] | ( header[4] << 8 );
 299     if( i_size > 0 )
 300     {
 301         /* msg_Dbg( p_demux, "frame audio size=%d", i_size ); */
 302         if( p_sys->fmt_audio.i_codec == VLC_FOURCC( 'a', 'r', 'a', 'w' ) )
 303         {
 304             uint8_t h[4];
 305             if( vlc_stream_Read( p_demux->s, h, 4 ) < 4 )
 306                 return VLC_DEMUXER_EOF;
 307
 308             p_sys->fmt_audio.audio.i_channels = h[1];
 309             p_sys->fmt_audio.audio.i_rate = GetWLE( &h[2] );
 310
 311             i_size -= 4;
 312         }
 313         if( p_sys->p_audio == NULL )
 314         {
 315             p_sys->p_audio = es_out_Add( p_demux->out, &p_sys->fmt_audio );
 316         }
 317
 318         if( ( p_frame = vlc_stream_Block( p_demux->s, i_size ) ) )
 319         {
 320             p_frame->i_dts =
 321             p_frame->i_pts = VLC_TICK_0 + p_sys->i_pcr;
 322
 323             if( p_sys->p_audio )
 324                 es_out_Send( p_demux->out, p_sys->p_audio, p_frame );
 325             else
 326             {
 327                 block_Release( p_frame );
 328                 msg_Dbg( p_demux, "ignoring unsupported audio frame (size=%d)",
 329                          i_size );
 330             }
 331         }
 332     }
 333
 334     p_sys->i_pcr += p_sys->i_pcr_inc;
 335     if( p_sys->i_time >= 0 )
 336     {
 337         p_sys->i_time += p_sys->i_pcr_inc;
 338     }
 339
 340     return VLC_DEMUXER_SUCCESS;
 341 }
 342
 343 /*****************************************************************************
 344  * Control:
 345  *****************************************************************************/
 346 static int Control( demux_t *p_demux, int i_query, va_list args )
 347 {
 348     demux_sys_t *p_sys = p_demux->p_sys;
 349     double f, *pf;
 350     bool b_bool, *pb_bool;
 351     int64_t i64, *pi64;
 352
 353     switch( i_query )
 354     {
 355         case DEMUX_CAN_SEEK:
 356             return vlc_stream_vaControl( p_demux->s, i_query, args );
 357
 358         case DEMUX_GET_POSITION:
 359             pf = va_arg( args, double * );
 360             i64 = stream_Size( p_demux->s );
 361             if( i64 > 0 )
 362             {
 363                 double current = vlc_stream_Tell( p_demux->s );
 364                 *pf = current / (double)i64;
 365             }
 366             else
 367             {
 368                 *pf = 0.0;
 369             }
 370             return VLC_SUCCESS;
 371
 372         case DEMUX_SET_POSITION:
 373             f = va_arg( args, double );
 374             i64 = stream_Size( p_demux->s );
 375
 376             if( vlc_stream_Seek( p_demux->s, (int64_t)(i64 * f) ) || ReSynch( p_demux ) )
 377                 return VLC_EGENERIC;
 378
 379             p_sys->i_time = -1; /* Invalidate time display */
 380             return VLC_SUCCESS;
 381
 382         case DEMUX_GET_TIME:
 383             pi64 = va_arg( args, int64_t * );
 384             if( p_sys->i_time < 0 )
 385             {
 386                 *pi64 = 0;
 387                 return VLC_EGENERIC;
 388             }
 389             *pi64 = p_sys->i_time;
 390             return VLC_SUCCESS;
 391
 392 #if 0
 393         case DEMUX_GET_LENGTH:
 394             pi64 = va_arg( args, int64_t * );
 395             if( p_sys->i_mux_rate > 0 )
 396             {
 397                 *pi64 = CLOCK_FREQ * ( stream_Size( p_demux->s ) / 50 ) / p_sys->i_mux_rate;
 398                 return VLC_SUCCESS;
 399             }
 400             *pi64 = 0;
 401             return VLC_EGENERIC;
 402
 403 #endif
 404         case DEMUX_GET_FPS:
 405             pf = va_arg( args, double * );
 406             *pf = (double)1000000.0 / (double)p_sys->i_pcr_inc;
 407             return VLC_SUCCESS;
 408
 409         case DEMUX_CAN_RECORD:
 410             pb_bool = va_arg( args, bool * );
 411             *pb_bool = true;
 412             return VLC_SUCCESS;
 413
 414         case DEMUX_SET_RECORD_STATE:
 415             b_bool = (bool)va_arg( args, int );
 416
 417             if( !b_bool )
 418                 vlc_stream_Control( p_demux->s, STREAM_SET_RECORD_STATE, false );
 419             p_sys->b_start_record = b_bool;
 420             return VLC_SUCCESS;
 421
 422
 423         case DEMUX_SET_TIME:
 424             return VLC_EGENERIC;
 425
 426         case DEMUX_CAN_PAUSE:
 427         case DEMUX_SET_PAUSE_STATE:
 428         case DEMUX_CAN_CONTROL_PACE:
 429         case DEMUX_GET_PTS_DELAY:
 430             return demux_vaControlHelper( p_demux->s, 0, -1, 0, 1, i_query, args );
 431
 432         default:
 433             return VLC_EGENERIC;
 434     }
 435 }
 436
 437 /*****************************************************************************
 438  * ReSynch:
 439  *****************************************************************************/
 440 static int ReSynch( demux_t *p_demux )
 441 {
 442     for( ;; )
 443     {
 444         const uint8_t *p_peek;
 445         int i_peek = vlc_stream_Peek( p_demux->s, &p_peek, 1024 );
 446         if( i_peek < 8 )
 447             break;
 448
 449         int i_skip = 0;
 450
 451         while( i_skip < i_peek - 4 )
 452         {
 453             if( !memcmp( p_peek, "NSVf", 4 )
 454              || !memcmp( p_peek, "NSVs", 4 ) )
 455             {
 456                 if( i_skip > 0
 457                  && vlc_stream_Read( p_demux->s, NULL, i_skip ) < i_skip )
 458                     return VLC_EGENERIC;
 459                 return VLC_SUCCESS;
 460             }
 461             p_peek++;
 462             i_skip++;
 463         }
 464
 465         if( vlc_stream_Read( p_demux->s, NULL, i_skip ) < i_skip )
 466             break;
 467     }
 468     return VLC_EGENERIC;
 469 }
 470
 471 /*****************************************************************************
 472  * ReadNSVf:
 473  *****************************************************************************/
 474 static int ReadNSVf( demux_t *p_demux )
 475 {
 476     /* demux_sys_t *p_sys = p_demux->p_sys; */
 477     const uint8_t     *p;
 478
 479     msg_Dbg( p_demux, "new NSVf chunk" );
 480     if( vlc_stream_Peek( p_demux->s, &p, 8 ) < 8 )
 481     {
 482         return VLC_EGENERIC;
 483     }
 484
 485     uint32_t i_header_size = GetDWLE( &p[4] );
 486     msg_Dbg( p_demux, "    - size=%" PRIu32, i_header_size );
 487
 488     if( i_header_size == 0 || i_header_size == UINT32_MAX )
 489         return VLC_EGENERIC;
 490
 491
 492     return vlc_stream_Read( p_demux->s, NULL, i_header_size ) == i_header_size
 493         ? VLC_SUCCESS : VLC_EGENERIC;
 494 }
 495 /*****************************************************************************
 496  * ReadNSVs:
 497  *****************************************************************************/
 498 static int ReadNSVs( demux_t *p_demux )
 499 {
 500     demux_sys_t *p_sys = p_demux->p_sys;
 501     uint8_t      header[19];
 502     vlc_fourcc_t fcc;
 503
 504     if( vlc_stream_Read( p_demux->s, header, 19 ) < 19 )
 505     {
 506         msg_Warn( p_demux, "cannot read" );
 507         return VLC_EGENERIC;
 508     }
 509
 510     /* Video */
 511     switch( ( fcc = VLC_FOURCC( header[4], header[5], header[6], header[7] ) ) )
 512     {
 513         case VLC_FOURCC( 'V', 'P', '3', ' ' ):
 514         case VLC_FOURCC( 'V', 'P', '3', '0' ):
 515             fcc = VLC_FOURCC( 'V', 'P', '3', '0' );
 516             break;
 517
 518         case VLC_FOURCC( 'V', 'P', '3', '1' ):
 519             fcc = VLC_FOURCC( 'V', 'P', '3', '1' );
 520             break;
 521
 522         case VLC_FOURCC( 'V', 'P', '5', ' ' ):
 523         case VLC_FOURCC( 'V', 'P', '5', '0' ):
 524             fcc = VLC_FOURCC( 'V', 'P', '5', '0' );
 525             break;
 526         case VLC_FOURCC( 'V', 'P', '6', '0' ):
 527         case VLC_FOURCC( 'V', 'P', '6', '1' ):
 528         case VLC_FOURCC( 'V', 'P', '6', '2' ):
 529         case VLC_FOURCC( 'V', 'P', '8', '0' ):
 530         case VLC_FOURCC( 'H', '2', '6', '4' ):
 531         case VLC_FOURCC( 'N', 'O', 'N', 'E' ):
 532             break;
 533         default:
 534             msg_Err( p_demux, "unsupported video codec %4.4s", (char *)&fcc );
 535             break;
 536     }
 537     if( fcc != VLC_FOURCC( 'N', 'O', 'N', 'E' ) && fcc != p_sys->fmt_video.i_codec  )
 538     {
 539         es_format_Init( &p_sys->fmt_video, VIDEO_ES, fcc );
 540         p_sys->fmt_video.video.i_width = GetWLE( &header[12] );
 541         p_sys->fmt_video.video.i_height = GetWLE( &header[14] );
 542         p_sys->fmt_video.video.i_visible_width = p_sys->fmt_video.video.i_width;
 543         p_sys->fmt_video.video.i_visible_height = p_sys->fmt_video.video.i_height;
 544         if( p_sys->p_video )
 545         {
 546             es_out_Del( p_demux->out, p_sys->p_video );
 547         }
 548         p_sys->p_video = es_out_Add( p_demux->out, &p_sys->fmt_video );
 549
 550         msg_Dbg( p_demux, "    - video `%4.4s' %dx%d",
 551                  (char*)&fcc,
 552                  p_sys->fmt_video.video.i_width,
 553                  p_sys->fmt_video.video.i_height );
 554     }
 555
 556     /* Audio */
 557     switch( ( fcc = VLC_FOURCC( header[8], header[9], header[10], header[11] ) ) )
 558     {
 559         case VLC_FOURCC( 'M', 'P', '3', ' ' ):
 560             fcc = VLC_FOURCC( 'm', 'p', 'g', 'a' );
 561             break;
 562         case VLC_FOURCC( 'P', 'C', 'M', ' ' ):
 563             fcc = VLC_FOURCC( 'a', 'r', 'a', 'w' );
 564             break;
 565         case VLC_FOURCC( 'A', 'A', 'C', ' ' ):
 566         case VLC_FOURCC( 'A', 'A', 'C', 'P' ):
 567             fcc = VLC_FOURCC( 'm', 'p', '4', 'a' );
 568             break;
 569         case VLC_FOURCC( 'S', 'P', 'X', ' ' ):
 570             fcc = VLC_FOURCC( 's', 'p', 'x', ' ' );
 571             break;
 572         case VLC_FOURCC( 'N', 'O', 'N', 'E' ):
 573             break;
 574         default:
 575             msg_Err( p_demux, "unsupported audio codec %4.4s", (char *)&fcc );
 576             break;
 577     }
 578
 579     if( fcc != VLC_FOURCC( 'N', 'O', 'N', 'E' ) && fcc != p_sys->fmt_audio.i_codec )
 580     {
 581         msg_Dbg( p_demux, "    - audio `%4.4s'", (char*)&fcc );
 582
 583         if( p_sys->p_audio )
 584         {
 585             es_out_Del( p_demux->out, p_sys->p_audio );
 586             p_sys->p_audio = NULL;
 587         }
 588         es_format_Init( &p_sys->fmt_audio, AUDIO_ES, fcc );
 589     }
 590
 591     if( header[16]&0x80 )
 592     {
 593         /* Fractional frame rate */
 594         switch( header[16]&0x03 )
 595         {
 596             case 0: /* 30 fps */
 597                 p_sys->i_pcr_inc = 33333; /* 300000/9 */
 598                 break;
 599             case 1: /* 29.97 fps */
 600                 p_sys->i_pcr_inc = 33367; /* 300300/9 */
 601                 break;
 602             case 2: /* 25 fps */
 603                 p_sys->i_pcr_inc = 40000; /* 360000/9 */
 604                 break;
 605             case 3: /* 23.98 fps */
 606                 p_sys->i_pcr_inc = 41700; /* 375300/9 */
 607                 break;
 608         }
 609
 610         if( header[16] < 0xc0 )
 611             p_sys->i_pcr_inc = p_sys->i_pcr_inc * (((header[16] ^ 0x80) >> 2 ) +1 );
 612         else
 613             p_sys->i_pcr_inc = p_sys->i_pcr_inc / (((header[16] ^ 0xc0) >> 2 ) +1 );
 614     }
 615     else if( header[16] != 0 )
 616     {
 617         /* Integer frame rate */
 618         p_sys->i_pcr_inc = 1000000 / header[16];
 619     }
 620     else
 621     {
 622         msg_Dbg( p_demux, "invalid fps (0x00)" );
 623         p_sys->i_pcr_inc = 40000;
 624     }
 625     //msg_Dbg( p_demux, "    - fps=%.3f", 1000000.0 / (double)p_sys->i_pcr_inc );
 626
 627     if( p_sys->p_audio == NULL && p_sys->p_video == NULL )
 628     {
 629         msg_Err( p_demux, "unable to play neither audio nor video, aborting." );
 630         return VLC_EGENERIC;
 631     }
 632
 633     return VLC_SUCCESS;
 634 }
 635