git.sesse.net Git - vlc/blob - src/video_output/video_output.c

   1 /*****************************************************************************
   2  * video_output.c : video output thread
   3  * This module describes the programming interface for video output threads.
   4  * It includes functions allowing to open a new thread, send pictures to a
   5  * thread, and destroy a previously oppened video output thread.
   6  *****************************************************************************
   7  * Copyright (C) 2000-2001 VideoLAN
   8  * $Id: video_output.c,v 1.166 2002/03/15 04:41:54 sam Exp $
   9  *
  10  * Authors: Vincent Seguin <seguin@via.ecp.fr>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  25  *****************************************************************************/
  26
  27 /*****************************************************************************
  28  * Preamble
  29  *****************************************************************************/
  30 #include <errno.h>                                                 /* ENOMEM */
  31 #include <stdlib.h>                                                /* free() */
  32 #include <stdio.h>                                              /* sprintf() */
  33 #include <string.h>                                            /* strerror() */
  34
  35 #include <videolan/vlc.h>
  36
  37 #ifdef HAVE_SYS_TIMES_H
  38 #   include <sys/times.h>
  39 #endif
  40
  41 #include "video.h"
  42 #include "video_output.h"
  43
  44 /*****************************************************************************
  45  * Local prototypes
  46  *****************************************************************************/
  47 static int      InitThread        ( vout_thread_t *p_vout );
  48 static void     RunThread         ( vout_thread_t *p_vout );
  49 static void     ErrorThread       ( vout_thread_t *p_vout );
  50 static void     EndThread         ( vout_thread_t *p_vout );
  51 static void     DestroyThread     ( vout_thread_t *p_vout, int i_status );
  52 static int      ReduceHeight      ( int );
  53
  54 /*****************************************************************************
  55  * vout_InitBank: initialize the video output bank.
  56  *****************************************************************************/
  57 void vout_InitBank ( void )
  58 {
  59     p_vout_bank->i_count = 0;
  60
  61     vlc_mutex_init( &p_vout_bank->lock );
  62 }
  63
  64 /*****************************************************************************
  65  * vout_EndBank: empty the video output bank.
  66  *****************************************************************************
  67  * This function ends all unused video outputs and empties the bank in
  68  * case of success.
  69  *****************************************************************************/
  70 void vout_EndBank ( void )
  71 {
  72     /* Ask all remaining video outputs to die */
  73     while( p_vout_bank->i_count )
  74     {
  75         vout_DestroyThread(
  76                 p_vout_bank->pp_vout[ --p_vout_bank->i_count ], NULL );
  77     }
  78
  79     vlc_mutex_destroy( &p_vout_bank->lock );
  80 }
  81
  82 /*****************************************************************************
  83  * vout_CreateThread: creates a new video output thread
  84  *****************************************************************************
  85  * This function creates a new video output thread, and returns a pointer
  86  * to its description. On error, it returns NULL.
  87  * If pi_status is NULL, then the function will block until the thread is ready.
  88  * If not, it will be updated using one of the THREAD_* constants.
  89  *****************************************************************************/
  90 vout_thread_t * vout_CreateThread   ( int *pi_status,
  91                                       int i_width, int i_height,
  92                                       u32 i_chroma, int i_aspect )
  93 {
  94     vout_thread_t * p_vout;                             /* thread descriptor */
  95     int             i_status;                               /* thread status */
  96     int             i_index;                                /* loop variable */
  97     char          * psz_plugin;
  98
  99     /* Allocate descriptor */
 100     p_vout = (vout_thread_t *) malloc( sizeof(vout_thread_t) );
 101     if( p_vout == NULL )
 102     {
 103         intf_ErrMsg( "vout error: vout thread creation returned %s",
 104                      strerror(ENOMEM) );
 105         return( NULL );
 106     }
 107
 108     /* Choose the best module */
 109     if( !(psz_plugin = config_GetPszVariable( "filter" )) )
 110     {
 111         psz_plugin = config_GetPszVariable( "vout" );
 112     }
 113
 114     /* Initialize thread properties - thread id and locks will be initialized
 115      * later */
 116     p_vout->b_die               = 0;
 117     p_vout->b_error             = 0;
 118     p_vout->b_active            = 0;
 119     p_vout->pi_status           = (pi_status != NULL) ? pi_status : &i_status;
 120     *p_vout->pi_status          = THREAD_CREATE;
 121
 122     /* Initialize pictures and subpictures - translation tables and functions
 123      * will be initialized later in InitThread */
 124     for( i_index = 0; i_index < VOUT_MAX_PICTURES; i_index++)
 125     {
 126         p_vout->p_picture[i_index].i_status = FREE_PICTURE;
 127         p_vout->p_picture[i_index].i_type   = EMPTY_PICTURE;
 128     }
 129
 130     for( i_index = 0; i_index < VOUT_MAX_SUBPICTURES; i_index++)
 131     {
 132         p_vout->p_subpicture[i_index].i_status = FREE_SUBPICTURE;
 133         p_vout->p_subpicture[i_index].i_type   = EMPTY_SUBPICTURE;
 134     }
 135
 136     /* Initialize the rendering heap */
 137     p_vout->i_heap_size = 0;
 138
 139     I_RENDERPICTURES = 0;
 140     p_vout->render.i_width    = i_width;
 141     p_vout->render.i_height   = i_height;
 142     p_vout->render.i_chroma   = i_chroma;
 143     p_vout->render.i_aspect   = i_aspect;
 144
 145     /* Initialize misc stuff */
 146     p_vout->i_changes    = 0;
 147     p_vout->f_gamma      = 0;
 148     p_vout->b_grayscale  = 0;
 149     p_vout->b_info       = 0;
 150     p_vout->b_interface  = 0;
 151     p_vout->b_scale      = 1;
 152     p_vout->b_fullscreen = 0;
 153     p_vout->render_time  = 10;
 154     p_vout->c_fps_samples= 0;
 155
 156     /* user requested fullscreen? */
 157     if( config_GetIntVariable( "fullscreen" ) )
 158         p_vout->i_changes |= VOUT_FULLSCREEN_CHANGE;
 159
 160     p_vout->p_module
 161         = module_Need( MODULE_CAPABILITY_VOUT, psz_plugin, (void *)p_vout );
 162
 163     if( psz_plugin ) free( psz_plugin );
 164     if( p_vout->p_module == NULL )
 165     {
 166         intf_ErrMsg( "vout error: no suitable vout module" );
 167         free( p_vout );
 168         return( NULL );
 169     }
 170
 171 #define f p_vout->p_module->p_functions->vout.functions.vout
 172     p_vout->pf_create     = f.pf_create;
 173     p_vout->pf_init       = f.pf_init;
 174     p_vout->pf_end        = f.pf_end;
 175     p_vout->pf_destroy    = f.pf_destroy;
 176     p_vout->pf_manage     = f.pf_manage;
 177     p_vout->pf_render     = f.pf_render;
 178     p_vout->pf_display    = f.pf_display;
 179 #undef f
 180
 181     /* Create thread and set locks */
 182     vlc_mutex_init( &p_vout->picture_lock );
 183     vlc_mutex_init( &p_vout->subpicture_lock );
 184     vlc_mutex_init( &p_vout->change_lock );
 185
 186     if( vlc_thread_create( &p_vout->thread_id, "video output",
 187                            (void *) RunThread, (void *) p_vout) )
 188     {
 189         intf_ErrMsg("vout error: %s", strerror(ENOMEM));
 190         p_vout->pf_destroy( p_vout );
 191         module_Unneed( p_vout->p_module );
 192         free( p_vout );
 193         return( NULL );
 194     }
 195
 196     /* If status is NULL, wait until the thread is created */
 197     if( pi_status == NULL )
 198     {
 199         do
 200         {
 201             msleep( THREAD_SLEEP );
 202         }while( (i_status != THREAD_READY) && (i_status != THREAD_ERROR)
 203                 && (i_status != THREAD_FATAL) );
 204         if( i_status != THREAD_READY )
 205         {
 206             return( NULL );
 207         }
 208     }
 209
 210     return( p_vout );
 211 }
 212
 213 /*****************************************************************************
 214  * vout_DestroyThread: destroys a previously created thread
 215  *****************************************************************************
 216  * Destroy a terminated thread.
 217  * The function will request a destruction of the specified thread. If pi_error
 218  * is NULL, it will return once the thread is destroyed. Else, it will be
 219  * update using one of the THREAD_* constants.
 220  *****************************************************************************/
 221 void vout_DestroyThread( vout_thread_t *p_vout, int *pi_status )
 222 {
 223     int     i_status;                                       /* thread status */
 224
 225     /* Set status */
 226     p_vout->pi_status = (pi_status != NULL) ? pi_status : &i_status;
 227     *p_vout->pi_status = THREAD_DESTROY;
 228
 229     /* Request thread destruction */
 230     p_vout->b_die = 1;
 231
 232     /* If status is NULL, wait until thread has been destroyed */
 233     if( pi_status == NULL )
 234     {
 235         do
 236         {
 237             msleep( THREAD_SLEEP );
 238         } while( (i_status != THREAD_OVER) && (i_status != THREAD_ERROR)
 239                  && (i_status != THREAD_FATAL) );
 240     }
 241 }
 242
 243 /*****************************************************************************
 244  * InitThread: initialize video output thread
 245  *****************************************************************************
 246  * This function is called from RunThread and performs the second step of the
 247  * initialization. It returns 0 on success. Note that the thread's flag are not
 248  * modified inside this function.
 249  *****************************************************************************/
 250 static int InitThread( vout_thread_t *p_vout )
 251 {
 252     int i, i_pgcd;
 253
 254     /* Update status */
 255     *p_vout->pi_status = THREAD_START;
 256
 257     vlc_mutex_lock( &p_vout->change_lock );
 258
 259 #ifdef STATS
 260     p_vout->c_loops = 0;
 261 #endif
 262
 263     /* Initialize output method, it issues its own error messages */
 264     if( p_vout->pf_init( p_vout ) )
 265     {
 266         vlc_mutex_unlock( &p_vout->change_lock );
 267         return( 1 );
 268     }
 269
 270     if( !I_OUTPUTPICTURES )
 271     {
 272         intf_ErrMsg( "vout error: plugin was unable to allocate at least "
 273                      "one direct buffer" );
 274         p_vout->pf_end( p_vout );
 275         vlc_mutex_unlock( &p_vout->change_lock );
 276         return( 1 );
 277     }
 278
 279     intf_WarnMsg( 1, "vout info: got %i direct buffer(s)", I_OUTPUTPICTURES );
 280
 281     i_pgcd = ReduceHeight( p_vout->render.i_aspect );
 282     intf_WarnMsg( 1, "vout info: picture in %ix%i, chroma 0x%.8x (%4.4s), "
 283                      "aspect ratio %i:%i",
 284                   p_vout->render.i_width, p_vout->render.i_height,
 285                   p_vout->render.i_chroma, (char*)&p_vout->render.i_chroma,
 286                   p_vout->render.i_aspect / i_pgcd,
 287                   VOUT_ASPECT_FACTOR / i_pgcd );
 288
 289     i_pgcd = ReduceHeight( p_vout->output.i_aspect );
 290     intf_WarnMsg( 1, "vout info: picture out %ix%i, chroma 0x%.8x (%4.4s), "
 291                      "aspect ratio %i:%i",
 292                   p_vout->output.i_width, p_vout->output.i_height,
 293                   p_vout->output.i_chroma, (char*)&p_vout->output.i_chroma,
 294                   p_vout->output.i_aspect / i_pgcd,
 295                   VOUT_ASPECT_FACTOR / i_pgcd );
 296
 297     /* Check whether we managed to create direct buffers similar to
 298      * the render buffers, ie same size, chroma and aspect ratio */
 299     if( ( p_vout->output.i_width == p_vout->render.i_width )
 300      && ( p_vout->output.i_height == p_vout->render.i_height )
 301      && ( vout_ChromaCmp( p_vout->output.i_chroma, p_vout->render.i_chroma ) )
 302      && ( p_vout->output.i_aspect == p_vout->render.i_aspect ) )
 303     {
 304         /* Cool ! We have direct buffers, we can ask the decoder to
 305          * directly decode into them ! Map the first render buffers to
 306          * the first direct buffers, but keep the first direct buffer
 307          * for memcpy operations */
 308         p_vout->b_direct = 1;
 309
 310         intf_WarnMsg( 2, "vout info: direct render, mapping "
 311                          "render pictures 0-%i to system pictures 1-%i",
 312                          VOUT_MAX_PICTURES - 2, VOUT_MAX_PICTURES - 1 );
 313
 314         for( i = 1; i < VOUT_MAX_PICTURES; i++ )
 315         {
 316             PP_RENDERPICTURE[ I_RENDERPICTURES ] = &p_vout->p_picture[ i ];
 317             I_RENDERPICTURES++;
 318         }
 319
 320     }
 321     else
 322     {
 323         /* Rats... Something is wrong here, we could not find an output
 324          * plugin able to directly render what we decode. See if we can
 325          * find a chroma plugin to do the conversion */
 326         p_vout->b_direct = 0;
 327
 328         /* Choose the best module */
 329         p_vout->chroma.p_module
 330             = module_Need( MODULE_CAPABILITY_CHROMA, NULL, (void *)p_vout );
 331
 332         if( p_vout->chroma.p_module == NULL )
 333         {
 334             intf_ErrMsg( "vout error: no chroma module for %4.4s to %4.4s",
 335                          &p_vout->render.i_chroma, &p_vout->output.i_chroma );
 336             p_vout->pf_end( p_vout );
 337             vlc_mutex_unlock( &p_vout->change_lock );
 338             return( 1 );
 339         }
 340
 341 #define f p_vout->chroma.p_module->p_functions->chroma.functions.chroma
 342         p_vout->chroma.pf_init       = f.pf_init;
 343         p_vout->chroma.pf_end        = f.pf_end;
 344 #undef f
 345
 346         if( p_vout->chroma.pf_init( p_vout ) )
 347         {
 348             intf_ErrMsg( "vout error: could not initialize chroma module" );
 349             module_Unneed( p_vout->chroma.p_module );
 350             p_vout->pf_end( p_vout );
 351             vlc_mutex_unlock( &p_vout->change_lock );
 352             return( 1 );
 353         }
 354
 355         if( I_OUTPUTPICTURES < VOUT_MAX_PICTURES )
 356         {
 357             intf_WarnMsg( 2, "vout info: indirect render, mapping "
 358                              "render pictures %i-%i to system pictures %i-%i",
 359                              I_OUTPUTPICTURES - 1, VOUT_MAX_PICTURES - 2,
 360                              I_OUTPUTPICTURES, VOUT_MAX_PICTURES - 1 );
 361         }
 362         else
 363         {
 364             intf_WarnMsg( 2, "vout info: indirect render, no system "
 365                              "pictures needed, we have %i directbuffers",
 366                              I_OUTPUTPICTURES );
 367         }
 368
 369         /* Append render buffers after the direct buffers */
 370         for( i = I_OUTPUTPICTURES; i < VOUT_MAX_PICTURES; i++ )
 371         {
 372             PP_RENDERPICTURE[ I_RENDERPICTURES ] = &p_vout->p_picture[ i ];
 373             I_RENDERPICTURES++;
 374         }
 375     }
 376
 377     /* Mark thread as running and return */
 378     p_vout->b_active = 1;
 379     *p_vout->pi_status = THREAD_READY;
 380
 381     return( 0 );
 382 }
 383
 384 /*****************************************************************************
 385  * RunThread: video output thread
 386  *****************************************************************************
 387  * Video output thread. This function does only returns when the thread is
 388  * terminated. It handles the pictures arriving in the video heap and the
 389  * display device events.
 390  *****************************************************************************/
 391 static void RunThread( vout_thread_t *p_vout)
 392 {
 393     int             i_index;                                /* index in heap */
 394     mtime_t         current_date;                            /* current date */
 395     mtime_t         display_date;                            /* display date */
 396
 397     picture_t *     p_picture;                            /* picture pointer */
 398     picture_t *     p_directbuffer;              /* direct buffer to display */
 399
 400     subpicture_t *  p_subpic;                          /* subpicture pointer */
 401
 402     /*
 403      * Initialize thread
 404      */
 405     p_vout->b_error = InitThread( p_vout );
 406     if( p_vout->b_error )
 407     {
 408         /* Destroy thread structures allocated by Create and InitThread */
 409         p_vout->pf_destroy( p_vout );
 410
 411         DestroyThread( p_vout, THREAD_ERROR );
 412         return;
 413     }
 414
 415     /*
 416      * Main loop - it is not executed if an error occured during
 417      * initialization
 418      */
 419     while( (!p_vout->b_die) && (!p_vout->b_error) )
 420     {
 421         /* Initialize loop variables */
 422         display_date = 0;
 423         current_date = mdate();
 424
 425 #ifdef STATS
 426         p_vout->c_loops++;
 427         if( !(p_vout->c_loops % VOUT_STATS_NB_LOOPS) )
 428         {
 429             intf_Msg( "vout stats: picture heap: %d/%d",
 430                       I_RENDERPICTURES, p_vout->i_heap_size );
 431         }
 432 #endif
 433
 434         /*
 435          * Find the picture to display - this operation does not need lock,
 436          * since only READY_PICTUREs are handled
 437          */
 438         p_picture = NULL;
 439
 440         for( i_index = 0;
 441              i_index < I_RENDERPICTURES;
 442              i_index++ )
 443         {
 444             if( (PP_RENDERPICTURE[i_index]->i_status == READY_PICTURE)
 445                 && ( (p_picture == NULL) ||
 446                      (PP_RENDERPICTURE[i_index]->date < display_date) ) )
 447             {
 448                 p_picture = PP_RENDERPICTURE[i_index];
 449                 display_date = p_picture->date;
 450             }
 451         }
 452
 453         if( p_picture != NULL )
 454         {
 455             /* Compute FPS rate */
 456             p_vout->p_fps_sample[ p_vout->c_fps_samples++ % VOUT_FPS_SAMPLES ]
 457                 = display_date;
 458
 459             if( display_date < current_date + p_vout->render_time )
 460             {
 461                 /* Picture is late: it will be destroyed and the thread
 462                  * will directly choose the next picture */
 463                 vlc_mutex_lock( &p_vout->picture_lock );
 464                 if( p_picture->i_refcount )
 465                 {
 466                     /* Pretend we displayed the picture, but don't destroy
 467                      * it since the decoder might still need it. */
 468                     p_picture->i_status = DISPLAYED_PICTURE;
 469                 }
 470                 else
 471                 {
 472                     /* Destroy the picture without displaying it */
 473                     p_picture->i_status = DESTROYED_PICTURE;
 474                     p_vout->i_heap_size--;
 475                 }
 476                 intf_WarnMsg( 1, "vout warning: late picture skipped (%p)",
 477                               p_picture );
 478                 vlc_mutex_unlock( &p_vout->picture_lock );
 479
 480                 continue;
 481             }
 482             else if( display_date > current_date + VOUT_DISPLAY_DELAY )
 483             {
 484                 /* A picture is ready to be rendered, but its rendering date
 485                  * is far from the current one so the thread will perform an
 486                  * empty loop as if no picture were found. The picture state
 487                  * is unchanged */
 488                 p_picture    = NULL;
 489                 display_date = 0;
 490             }
 491         }
 492
 493         /*
 494          * Check for subpictures to display
 495          */
 496         p_subpic = vout_SortSubPictures( p_vout, display_date );
 497
 498         /*
 499          * Perform rendering
 500          */
 501         p_directbuffer = vout_RenderPicture( p_vout, p_picture, p_subpic );
 502
 503         /*
 504          * Call the plugin-specific rendering method
 505          */
 506         if( p_picture != NULL )
 507         {
 508             /* Render the direct buffer returned by vout_RenderPicture */
 509             p_vout->pf_render( p_vout, p_directbuffer );
 510         }
 511
 512         /*
 513          * Sleep, wake up
 514          */
 515         if( display_date != 0 )
 516         {
 517             /* Store render time using Bresenham algorithm */
 518             p_vout->render_time += mdate() - current_date;
 519             p_vout->render_time >>= 1;
 520         }
 521
 522         /* Give back change lock */
 523         vlc_mutex_unlock( &p_vout->change_lock );
 524
 525         /* Sleep a while or until a given date */
 526         if( display_date != 0 )
 527         {
 528             mwait( display_date - VOUT_MWAIT_TOLERANCE );
 529         }
 530         else
 531         {
 532             msleep( VOUT_IDLE_SLEEP );
 533         }
 534
 535         /* On awakening, take back lock and send immediately picture
 536          * to display. */
 537         vlc_mutex_lock( &p_vout->change_lock );
 538
 539         /*
 540          * Display the previously rendered picture
 541          */
 542         if( p_picture != NULL )
 543         {
 544             /* Display the direct buffer returned by vout_RenderPicture */
 545             p_vout->pf_display( p_vout, p_directbuffer );
 546
 547             /* Remove picture from heap */
 548             vlc_mutex_lock( &p_vout->picture_lock );
 549             if( p_picture->i_refcount )
 550             {
 551                 p_picture->i_status = DISPLAYED_PICTURE;
 552             }
 553             else
 554             {
 555                 p_picture->i_status = DESTROYED_PICTURE;
 556                 p_vout->i_heap_size--;
 557             }
 558             vlc_mutex_unlock( &p_vout->picture_lock );
 559         }
 560
 561         /*
 562          * Check events and manage thread
 563          */
 564         if( p_vout->pf_manage( p_vout ) )
 565         {
 566             /* A fatal error occured, and the thread must terminate immediately,
 567              * without displaying anything - setting b_error to 1 causes the
 568              * immediate end of the main while() loop. */
 569             p_vout->b_error = 1;
 570         }
 571     }
 572
 573     /*
 574      * Error loop - wait until the thread destruction is requested
 575      */
 576     if( p_vout->b_error )
 577     {
 578         ErrorThread( p_vout );
 579     }
 580
 581     /* End of thread */
 582     EndThread( p_vout );
 583
 584     /* Destroy method-dependant resources */
 585     p_vout->pf_destroy( p_vout );
 586
 587     /* Destroy thread structures allocated by CreateThread */
 588     DestroyThread( p_vout, THREAD_OVER );
 589 }
 590
 591 /*****************************************************************************
 592  * ErrorThread: RunThread() error loop
 593  *****************************************************************************
 594  * This function is called when an error occured during thread main's loop. The
 595  * thread can still receive feed, but must be ready to terminate as soon as
 596  * possible.
 597  *****************************************************************************/
 598 static void ErrorThread( vout_thread_t *p_vout )
 599 {
 600     /* Wait until a `die' order */
 601     while( !p_vout->b_die )
 602     {
 603         /* Sleep a while */
 604         msleep( VOUT_IDLE_SLEEP );
 605     }
 606 }
 607
 608 /*****************************************************************************
 609  * EndThread: thread destruction
 610  *****************************************************************************
 611  * This function is called when the thread ends after a sucessful
 612  * initialization. It frees all ressources allocated by InitThread.
 613  *****************************************************************************/
 614 static void EndThread( vout_thread_t *p_vout )
 615 {
 616     int     i_index;                                        /* index in heap */
 617
 618     /* Store status */
 619     *p_vout->pi_status = THREAD_END;
 620
 621 #ifdef STATS
 622     {
 623         struct tms cpu_usage;
 624         times( &cpu_usage );
 625
 626         intf_Msg( "vout stats: cpu usage (user: %d, system: %d)",
 627                   cpu_usage.tms_utime, cpu_usage.tms_stime );
 628     }
 629 #endif
 630
 631     if( !p_vout->b_direct )
 632     {
 633         p_vout->chroma.pf_end( p_vout );
 634         module_Unneed( p_vout->chroma.p_module );
 635     }
 636
 637     /* Destroy all remaining pictures */
 638     for( i_index = 0; i_index < VOUT_MAX_PICTURES; i_index++ )
 639     {
 640         if ( p_vout->p_picture[i_index].i_type == MEMORY_PICTURE )
 641         {
 642             free( p_vout->p_picture[i_index].p_data );
 643         }
 644     }
 645
 646     /* Destroy all remaining subpictures */
 647     for( i_index = 0; i_index < VOUT_MAX_SUBPICTURES; i_index++ )
 648     {
 649         if( p_vout->p_subpicture[i_index].i_status != FREE_SUBPICTURE )
 650         {
 651             free( p_vout->p_subpicture[i_index].p_sys );
 652         }
 653     }
 654
 655     /* Destroy translation tables */
 656     p_vout->pf_end( p_vout );
 657
 658     /* Release the change lock */
 659     vlc_mutex_unlock( &p_vout->change_lock );
 660 }
 661
 662 /*****************************************************************************
 663  * DestroyThread: thread destruction
 664  *****************************************************************************
 665  * This function is called when the thread ends. It frees all ressources
 666  * allocated by CreateThread. Status is available at this stage.
 667  *****************************************************************************/
 668 static void DestroyThread( vout_thread_t *p_vout, int i_status )
 669 {
 670     int *pi_status;                                         /* status adress */
 671
 672     /* Store status adress */
 673     pi_status = p_vout->pi_status;
 674
 675     /* Destroy the locks */
 676     vlc_mutex_destroy( &p_vout->picture_lock );
 677     vlc_mutex_destroy( &p_vout->subpicture_lock );
 678     vlc_mutex_destroy( &p_vout->change_lock );
 679
 680     /* Release the module */
 681     module_Unneed( p_vout->p_module );
 682
 683     /* Free structure */
 684     free( p_vout );
 685     *pi_status = i_status;
 686 }
 687
 688 static int ReduceHeight( int i_ratio )
 689 {
 690     int i_dummy = VOUT_ASPECT_FACTOR;
 691     int i_pgcd  = 1;
 692
 693     if( !i_ratio )
 694     {
 695         return i_pgcd;
 696     }
 697
 698     /* VOUT_ASPECT_FACTOR is (2^7 * 3^3 * 5^3), we just check for 2, 3 and 5 */
 699     while( !(i_ratio & 1) && !(i_dummy & 1) )
 700     {
 701         i_ratio >>= 1;
 702         i_dummy >>= 1;
 703         i_pgcd  <<= 1;
 704     }
 705
 706     while( !(i_ratio % 3) && !(i_dummy % 3) )
 707     {
 708         i_ratio /= 3;
 709         i_dummy /= 3;
 710         i_pgcd  *= 3;
 711     }
 712
 713     while( !(i_ratio % 5) && !(i_dummy % 5) )
 714     {
 715         i_ratio /= 5;
 716         i_dummy /= 5;
 717         i_pgcd  *= 5;
 718     }
 719
 720     return i_pgcd;
 721 }
 722