git.sesse.net Git - vlc/blob - modules/codec/libmpeg2.c

   1 /*****************************************************************************
   2  * libmpeg2.c: mpeg2 video decoder module making use of libmpeg2.
   3  *****************************************************************************
   4  * Copyright (C) 1999-2001 VideoLAN
   5  * $Id: libmpeg2.c,v 1.24 2003/08/08 17:08:32 gbazin Exp $
   6  *
   7  * Authors: Gildas Bazin <gbazin@netcourrier.com>
   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 <vlc/vlc.h>
  28 #include <vlc/vout.h>
  29 #include <vlc/input.h>
  30 #include <vlc/decoder.h>
  31
  32 #include <stdlib.h>                                      /* malloc(), free() */
  33 #include <string.h>                                    /* memcpy(), memset() */
  34
  35 #include <mpeg2dec/mpeg2.h>
  36
  37 #include "vout_synchro.h"
  38
  39 /* Aspect ratio (ISO/IEC 13818-2 section 6.3.3, table 6-3) */
  40 #define AR_SQUARE_PICTURE       1                           /* square pixels */
  41 #define AR_3_4_PICTURE          2                        /* 3:4 picture (TV) */
  42 #define AR_16_9_PICTURE         3              /* 16:9 picture (wide screen) */
  43 #define AR_221_1_PICTURE        4                  /* 2.21:1 picture (movie) */
  44
  45 /*****************************************************************************
  46  * dec_thread_t : libmpeg2 decoder thread descriptor
  47  *****************************************************************************/
  48 typedef struct dec_thread_t
  49 {
  50     /*
  51      * libmpeg2 properties
  52      */
  53     mpeg2dec_t          *p_mpeg2dec;
  54     const mpeg2_info_t  *p_info;
  55     vlc_bool_t          b_skip;
  56
  57     /*
  58      * Input properties
  59      */
  60     decoder_fifo_t   *p_fifo;                  /* stores the PES stream data */
  61     pes_packet_t     *p_pes;                  /* current PES we are decoding */
  62     mtime_t          i_pts;
  63     mtime_t          i_previous_pts;
  64     mtime_t          i_current_pts;
  65     mtime_t          i_period_remainder;
  66     int              i_current_rate;
  67     picture_t *      p_picture_to_destroy;
  68     vlc_bool_t       b_garbage_pic;
  69     vlc_bool_t       b_after_sequence_header; /* is it the next frame after
  70                                                * the sequence header ?    */
  71     vlc_bool_t       b_slice_i;             /* intra-slice refresh stream */
  72
  73     /*
  74      * Output properties
  75      */
  76     vout_thread_t *p_vout;
  77     vout_synchro_t *p_synchro;
  78
  79 } dec_thread_t;
  80
  81 /*****************************************************************************
  82  * Local prototypes
  83  *****************************************************************************/
  84 static int  OpenDecoder  ( vlc_object_t * );
  85 static int  RunDecoder   ( decoder_fifo_t * );
  86 static void CloseDecoder ( dec_thread_t * );
  87
  88 static picture_t *GetNewPicture( dec_thread_t *, uint8_t ** );
  89
  90 /*****************************************************************************
  91  * Module descriptor
  92  *****************************************************************************/
  93 vlc_module_begin();
  94     set_description( _("MPEG I/II video decoder (using libmpeg2)") );
  95     set_capability( "decoder", 150 );
  96     set_callbacks( OpenDecoder, NULL );
  97     add_shortcut( "libmpeg2" );
  98 vlc_module_end();
  99
 100 /*****************************************************************************
 101  * OpenDecoder: probe the decoder and return score
 102  *****************************************************************************/
 103 static int OpenDecoder( vlc_object_t *p_this )
 104 {
 105     decoder_fifo_t *p_fifo = (decoder_fifo_t*) p_this;
 106
 107     if( p_fifo->i_fourcc != VLC_FOURCC('m','p','g','v') )
 108     {
 109         return VLC_EGENERIC;
 110     }
 111
 112     p_fifo->pf_run = RunDecoder;
 113     return VLC_SUCCESS;
 114 }
 115
 116 /*****************************************************************************
 117  * RunDecoder: the libmpeg2 decoder
 118  *****************************************************************************/
 119 static int RunDecoder( decoder_fifo_t *p_fifo )
 120 {
 121     dec_thread_t    *p_dec;
 122     data_packet_t   *p_data = NULL;
 123     mpeg2_state_t   state;
 124     picture_t       *p_pic;
 125     int             i_aspect;
 126     int             i_pic;
 127
 128     /* Allocate the memory needed to store the thread's structure */
 129     if( (p_dec = (dec_thread_t *)malloc (sizeof(dec_thread_t)) )
 130         == NULL)
 131     {
 132         msg_Err( p_fifo, "out of memory" );
 133         goto error;
 134     }
 135
 136     /* Initialize the thread properties */
 137     memset( p_dec, 0, sizeof(dec_thread_t) );
 138     p_dec->p_fifo     = p_fifo;
 139     p_dec->p_pes      = NULL;
 140     p_dec->p_vout     = NULL;
 141     p_dec->p_mpeg2dec = NULL;
 142     p_dec->p_synchro  = NULL;
 143     p_dec->p_info     = NULL;
 144     p_dec->i_pts      = mdate() + DEFAULT_PTS_DELAY;
 145     p_dec->i_current_pts  = 0;
 146     p_dec->i_previous_pts = 0;
 147     p_dec->i_period_remainder = 0;
 148     p_dec->p_picture_to_destroy = NULL;
 149     p_dec->b_garbage_pic = 0;
 150     p_dec->b_slice_i  = 0;
 151     p_dec->b_skip     = 0;
 152
 153     /* Initialize decoder */
 154     p_dec->p_mpeg2dec = mpeg2_init();
 155     if( p_dec->p_mpeg2dec == NULL)
 156         goto error;
 157
 158     p_dec->p_info = mpeg2_info( p_dec->p_mpeg2dec );
 159
 160     /* libmpeg2 decoder thread's main loop */
 161     while( (!p_dec->p_fifo->b_die) && (!p_dec->p_fifo->b_error) )
 162     {
 163         state = mpeg2_parse( p_dec->p_mpeg2dec );
 164
 165         switch( state )
 166         {
 167         case STATE_BUFFER:
 168             /* Feed libmpeg2 a data packet at a time */
 169             if( p_data == NULL )
 170             {
 171                 /* Get the next PES */
 172                 if( p_dec->p_pes )
 173                     input_DeletePES( p_dec->p_fifo->p_packets_mgt,
 174                                      p_dec->p_pes );
 175
 176                 input_ExtractPES( p_dec->p_fifo, &p_dec->p_pes );
 177                 if( !p_dec->p_pes )
 178                 {
 179                     p_dec->p_fifo->b_error = 1;
 180                     break;
 181                 }
 182
 183                 if( p_dec->p_pes->b_discontinuity && p_dec->p_synchro
 184                      && p_dec->p_info->sequence->width != (unsigned)-1 )
 185                 {
 186                     vout_SynchroReset( p_dec->p_synchro );
 187                     if ( p_dec->p_info->current_fbuf != NULL
 188                           && p_dec->p_info->current_fbuf->id != NULL )
 189                     {
 190                         p_dec->b_garbage_pic = 1;
 191                         p_pic = p_dec->p_info->current_fbuf->id;
 192                     }
 193                     else
 194                     {
 195                         uint8_t *buf[3];
 196                         buf[0] = buf[1] = buf[2] = NULL;
 197                         if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 198                             break;
 199                         mpeg2_set_buf( p_dec->p_mpeg2dec, buf, p_pic );
 200                     }
 201                     p_dec->p_picture_to_destroy = p_pic;
 202
 203                     memset( p_pic->p[0].p_pixels, 0,
 204                             p_dec->p_info->sequence->width
 205                              * p_dec->p_info->sequence->height );
 206                     memset( p_pic->p[1].p_pixels, 0x80,
 207                             p_dec->p_info->sequence->width
 208                              * p_dec->p_info->sequence->height / 4 );
 209                     memset( p_pic->p[2].p_pixels, 0x80,
 210                             p_dec->p_info->sequence->width
 211                              * p_dec->p_info->sequence->height / 4 );
 212
 213                     if ( p_dec->b_slice_i )
 214                     {
 215                         vout_SynchroNewPicture( p_dec->p_synchro,
 216                             I_CODING_TYPE, 2, 0, 0, p_dec->i_current_rate );
 217                         vout_SynchroDecode( p_dec->p_synchro );
 218                         vout_SynchroEnd( p_dec->p_synchro, I_CODING_TYPE, 0 );
 219                     }
 220                 }
 221
 222                 if( p_dec->p_pes->i_pts )
 223                 {
 224                     mpeg2_pts( p_dec->p_mpeg2dec,
 225                                (uint32_t)p_dec->p_pes->i_pts );
 226                     p_dec->i_previous_pts = p_dec->i_current_pts;
 227                     p_dec->i_current_pts = p_dec->p_pes->i_pts;
 228                 }
 229
 230                 p_dec->i_current_rate = p_dec->p_pes->i_rate;
 231                 p_data = p_dec->p_pes->p_first;
 232             }
 233
 234             if( p_data != NULL )
 235             {
 236                 mpeg2_buffer( p_dec->p_mpeg2dec,
 237                               p_data->p_payload_start,
 238                               p_data->p_payload_end );
 239
 240                 p_data = p_data->p_next;
 241             }
 242             break;
 243
 244         case STATE_SEQUENCE:
 245         {
 246             /* Initialize video output */
 247             uint8_t *buf[3];
 248             buf[0] = buf[1] = buf[2] = NULL;
 249
 250             /* Check whether the input gives a particular aspect ratio */
 251             if( p_dec->p_fifo->p_demux_data
 252                 && ( *(int*)(p_dec->p_fifo->p_demux_data) & 0x7 ) )
 253             {
 254                 i_aspect = *(int*)(p_dec->p_fifo->p_demux_data);
 255                 switch( i_aspect )
 256                 {
 257                 case AR_3_4_PICTURE:
 258                     i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 259                     break;
 260                 case AR_16_9_PICTURE:
 261                     i_aspect = VOUT_ASPECT_FACTOR * 16 / 9;
 262                     break;
 263                 case AR_221_1_PICTURE:
 264                     i_aspect = VOUT_ASPECT_FACTOR * 221 / 100;
 265                     break;
 266                 case AR_SQUARE_PICTURE:
 267                 default:
 268                     i_aspect = VOUT_ASPECT_FACTOR *
 269                                    p_dec->p_info->sequence->width /
 270                                    p_dec->p_info->sequence->height;
 271                     break;
 272                 }
 273             }
 274             else
 275             {
 276                 /* Use the value provided in the MPEG sequence header */
 277                 i_aspect = ((uint64_t)p_dec->p_info->sequence->display_width) *
 278                     p_dec->p_info->sequence->pixel_width * VOUT_ASPECT_FACTOR /
 279                     p_dec->p_info->sequence->display_height /
 280                     p_dec->p_info->sequence->pixel_height;
 281             }
 282
 283             if ( p_dec->p_vout != NULL )
 284             {
 285                 /* Temporary hack to free the pictures in use by libmpeg2 */
 286                 for ( i_pic = 0; i_pic < p_dec->p_vout->render.i_pictures; i_pic++ )
 287                 {
 288                     if( p_dec->p_vout->render.pp_picture[i_pic]->i_status ==
 289                           RESERVED_PICTURE )
 290                         vout_DestroyPicture( p_dec->p_vout,
 291                                          p_dec->p_vout->render.pp_picture[i_pic] );
 292                     if( p_dec->p_vout->render.pp_picture[i_pic]->i_refcount > 0 )
 293                         vout_UnlinkPicture( p_dec->p_vout,
 294                                          p_dec->p_vout->render.pp_picture[i_pic] );
 295                 }
 296             }
 297
 298             p_dec->p_vout = vout_Request( p_dec->p_fifo, p_dec->p_vout,
 299                                           p_dec->p_info->sequence->width,
 300                                           p_dec->p_info->sequence->height,
 301                                           VLC_FOURCC('Y','V','1','2'), i_aspect );
 302
 303             msg_Dbg( p_dec->p_fifo, "%dx%d, aspect %d, %u.%03u fps",
 304                      p_dec->p_info->sequence->width,
 305                      p_dec->p_info->sequence->height, i_aspect,
 306                      (u32)((u64)1001000000 * 27 / p_dec->p_info->sequence->frame_period / 1001),
 307                      (u32)((u64)1001000000 * 27 / p_dec->p_info->sequence->frame_period % 1001) );
 308
 309             mpeg2_custom_fbuf( p_dec->p_mpeg2dec, 1 );
 310
 311             /* Set the first 2 reference frames */
 312             mpeg2_set_buf( p_dec->p_mpeg2dec, buf, NULL );
 313
 314             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL ) break;
 315             memset( p_pic->p[0].p_pixels, 0,
 316                     p_dec->p_info->sequence->width
 317                      * p_dec->p_info->sequence->height );
 318             memset( p_pic->p[1].p_pixels, 0x80,
 319                     p_dec->p_info->sequence->width
 320                      * p_dec->p_info->sequence->height / 4 );
 321             memset( p_pic->p[2].p_pixels, 0x80,
 322                     p_dec->p_info->sequence->width
 323                      * p_dec->p_info->sequence->height / 4 );
 324             mpeg2_set_buf( p_dec->p_mpeg2dec, buf, p_pic );
 325             /* This picture will never go through display_picture. */
 326             vout_DatePicture( p_dec->p_vout, p_pic, 0 );
 327             vout_DisplayPicture( p_dec->p_vout, p_pic );
 328             /* For some reason, libmpeg2 will put this pic twice in
 329              * discard_picture. This can be considered a bug in libmpeg2. */
 330             vout_LinkPicture( p_dec->p_vout, p_pic );
 331
 332             if ( p_dec->p_synchro )
 333             {
 334                 vout_SynchroRelease( p_dec->p_synchro );
 335             }
 336             p_dec->p_synchro = vout_SynchroInit( p_dec->p_fifo, p_dec->p_vout,
 337                 (u32)((u64)1001000000 * 27 / p_dec->p_info->sequence->frame_period) );
 338             p_dec->b_after_sequence_header = 1;
 339         }
 340         break;
 341
 342         case STATE_PICTURE_2ND:
 343             vout_SynchroNewPicture( p_dec->p_synchro,
 344                 p_dec->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 345                 p_dec->p_info->current_picture->nb_fields,
 346                 0, 0,
 347                 p_dec->i_current_rate );
 348
 349             if ( p_dec->b_skip )
 350             {
 351                 vout_SynchroTrash( p_dec->p_synchro );
 352             }
 353             else
 354             {
 355                 vout_SynchroDecode( p_dec->p_synchro );
 356             }
 357             break;
 358
 359         case STATE_PICTURE:
 360         {
 361             uint8_t *buf[3];
 362             buf[0] = buf[1] = buf[2] = NULL;
 363
 364             if ( p_dec->b_after_sequence_header
 365                   && ((p_dec->p_info->current_picture->flags
 366                         & PIC_MASK_CODING_TYPE)
 367                        == PIC_FLAG_CODING_TYPE_P) )
 368             {
 369                 /* Intra-slice refresh. Simulate a blank I picture. */
 370                 msg_Dbg( p_dec->p_fifo, "intra-slice refresh stream" );
 371                 vout_SynchroNewPicture( p_dec->p_synchro,
 372                     I_CODING_TYPE, 2, 0, 0, p_dec->i_current_rate );
 373                 vout_SynchroDecode( p_dec->p_synchro );
 374                 vout_SynchroEnd( p_dec->p_synchro, I_CODING_TYPE, 0 );
 375                 p_dec->b_slice_i = 1;
 376             }
 377             p_dec->b_after_sequence_header = 0;
 378
 379             vout_SynchroNewPicture( p_dec->p_synchro,
 380                 p_dec->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 381                 p_dec->p_info->current_picture->nb_fields,
 382                 (p_dec->p_info->current_picture->flags & PIC_FLAG_PTS) ?
 383                     ( (p_dec->p_info->current_picture->pts ==
 384                                 (uint32_t)p_dec->i_current_pts) ?
 385                               p_dec->i_current_pts : p_dec->i_previous_pts ) : 0,
 386                 0,
 387                 p_dec->i_current_rate );
 388
 389             if ( !(p_dec->b_slice_i
 390                    && ((p_dec->p_info->current_picture->flags
 391                          & PIC_MASK_CODING_TYPE) == P_CODING_TYPE))
 392                    && !vout_SynchroChoose( p_dec->p_synchro,
 393                               p_dec->p_info->current_picture->flags
 394                                 & PIC_MASK_CODING_TYPE ) )
 395             {
 396                 mpeg2_skip( p_dec->p_mpeg2dec, 1 );
 397                 p_dec->b_skip = 1;
 398                 vout_SynchroTrash( p_dec->p_synchro );
 399                 mpeg2_set_buf( p_dec->p_mpeg2dec, buf, NULL );
 400             }
 401             else
 402             {
 403                 mpeg2_skip( p_dec->p_mpeg2dec, 0 );
 404                 p_dec->b_skip = 0;
 405                 vout_SynchroDecode( p_dec->p_synchro );
 406                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL ) break;
 407                 mpeg2_set_buf( p_dec->p_mpeg2dec, buf, p_pic );
 408             }
 409         }
 410         break;
 411
 412         case STATE_END:
 413         case STATE_SLICE:
 414             if( p_dec->p_info->display_fbuf
 415                 && p_dec->p_info->display_fbuf->id )
 416             {
 417                 p_pic = (picture_t *)p_dec->p_info->display_fbuf->id;
 418
 419                 vout_SynchroEnd( p_dec->p_synchro,
 420                             p_dec->p_info->display_picture->flags
 421                              & PIC_MASK_CODING_TYPE,
 422                             p_dec->b_garbage_pic );
 423                 p_dec->b_garbage_pic = 0;
 424                 vout_DisplayPicture( p_dec->p_vout, p_pic );
 425
 426                 if ( p_dec->p_picture_to_destroy != p_pic )
 427                 {
 428                     vout_DatePicture( p_dec->p_vout, p_pic,
 429                         vout_SynchroDate( p_dec->p_synchro ) );
 430                 }
 431                 else
 432                 {
 433                     p_dec->p_picture_to_destroy = NULL;
 434                     vout_DatePicture( p_dec->p_vout, p_pic, 0 );
 435                 }
 436             }
 437
 438             if( p_dec->p_info->discard_fbuf &&
 439                 p_dec->p_info->discard_fbuf->id )
 440             {
 441                 p_pic = (picture_t *)p_dec->p_info->discard_fbuf->id;
 442                 vout_UnlinkPicture( p_dec->p_vout, p_pic );
 443             }
 444             break;
 445
 446         case STATE_INVALID:
 447         {
 448             uint8_t *buf[3];
 449             buf[0] = buf[1] = buf[2] = NULL;
 450
 451             msg_Warn( p_dec->p_fifo, "invalid picture encountered" );
 452             if ( ( p_dec->p_info->current_picture == NULL ) ||
 453                ( ( p_dec->p_info->current_picture->flags & PIC_MASK_CODING_TYPE)
 454                   != B_CODING_TYPE ) )
 455             {
 456                 vout_SynchroReset( p_dec->p_synchro );
 457             }
 458             mpeg2_skip( p_dec->p_mpeg2dec, 1 );
 459             p_dec->b_skip = 1;
 460
 461             if( p_dec->p_info->current_fbuf &&
 462                 p_dec->p_info->current_fbuf->id )
 463             {
 464                 p_dec->b_garbage_pic = 1;
 465                 p_pic = p_dec->p_info->current_fbuf->id;
 466             }
 467             else
 468             {
 469                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 470                     break;
 471                 mpeg2_set_buf( p_dec->p_mpeg2dec, buf, p_pic );
 472             }
 473             p_dec->p_picture_to_destroy = p_pic;
 474
 475             memset( p_pic->p[0].p_pixels, 0,
 476                     p_dec->p_info->sequence->width
 477                      * p_dec->p_info->sequence->height );
 478             memset( p_pic->p[1].p_pixels, 0x80,
 479                     p_dec->p_info->sequence->width
 480                      * p_dec->p_info->sequence->height / 4 );
 481             memset( p_pic->p[2].p_pixels, 0x80,
 482                     p_dec->p_info->sequence->width
 483                      * p_dec->p_info->sequence->height / 4 );
 484
 485             if ( p_dec->b_slice_i )
 486             {
 487                 vout_SynchroNewPicture( p_dec->p_synchro,
 488                             I_CODING_TYPE, 2, 0, 0, p_dec->i_current_rate );
 489                 vout_SynchroDecode( p_dec->p_synchro );
 490                 vout_SynchroEnd( p_dec->p_synchro, I_CODING_TYPE, 0 );
 491             }
 492             break;
 493         }
 494
 495         default:
 496             break;
 497         }
 498     }
 499
 500     /* If b_error is set, the libmpeg2 decoder thread enters the error loop */
 501     if( p_dec->p_fifo->b_error )
 502     {
 503         DecoderError( p_dec->p_fifo );
 504     }
 505
 506     /* End of the libmpeg2 decoder thread */
 507     CloseDecoder( p_dec );
 508
 509     return 0;
 510
 511  error:
 512     DecoderError( p_fifo );
 513     if( p_dec )
 514     {
 515         if( p_dec->p_fifo )
 516             p_dec->p_fifo->b_error = 1;
 517
 518         /* End of the libmpeg2 decoder thread */
 519         CloseDecoder( p_dec );
 520     }
 521
 522     return -1;
 523 }
 524
 525 /*****************************************************************************
 526  * CloseDecoder: libmpeg2 decoder destruction
 527  *****************************************************************************/
 528 static void CloseDecoder( dec_thread_t * p_dec )
 529 {
 530     if( p_dec )
 531     {
 532         int i_pic;
 533
 534         if( p_dec->p_pes )
 535             input_DeletePES( p_dec->p_fifo->p_packets_mgt, p_dec->p_pes );
 536
 537         if( p_dec->p_synchro )
 538             vout_SynchroRelease( p_dec->p_synchro );
 539
 540         if( p_dec->p_vout )
 541         {
 542             /* Temporary hack to free the pictures in use by libmpeg2 */
 543             for( i_pic = 0; i_pic < p_dec->p_vout->render.i_pictures; i_pic++ )
 544             {
 545                 if( p_dec->p_vout->render.pp_picture[i_pic]->i_status ==
 546                       RESERVED_PICTURE )
 547                     vout_DestroyPicture( p_dec->p_vout,
 548                                      p_dec->p_vout->render.pp_picture[i_pic] );
 549                 if( p_dec->p_vout->render.pp_picture[i_pic]->i_refcount > 0 )
 550                     vout_UnlinkPicture( p_dec->p_vout,
 551                                      p_dec->p_vout->render.pp_picture[i_pic] );
 552             }
 553
 554             vout_Request( p_dec->p_fifo, p_dec->p_vout, 0, 0, 0, 0 );
 555         }
 556
 557         if( p_dec->p_mpeg2dec ) mpeg2_close( p_dec->p_mpeg2dec );
 558
 559         free( p_dec );
 560     }
 561 }
 562
 563 /*****************************************************************************
 564  * GetNewPicture: Get a new picture from the vout and set the buf struct
 565  *****************************************************************************/
 566 static picture_t *GetNewPicture( dec_thread_t *p_dec, uint8_t **pp_buf )
 567 {
 568     picture_t *p_pic;
 569     vlc_bool_t b_progressive = p_dec->p_info->current_picture != NULL ?
 570         p_dec->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME :
 571         1;
 572     vlc_bool_t b_top_field_first = p_dec->p_info->current_picture != NULL ?
 573         p_dec->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST :
 574         1;
 575     unsigned int i_nb_fields = p_dec->p_info->current_picture != NULL ?
 576         p_dec->p_info->current_picture->nb_fields : 2;
 577
 578     /* Get a new picture */
 579     while( !(p_pic = vout_CreatePicture( p_dec->p_vout,
 580         b_progressive, b_top_field_first, i_nb_fields )) )
 581     {
 582         if( p_dec->p_fifo->b_die || p_dec->p_fifo->b_error )
 583             break;
 584
 585         msleep( VOUT_OUTMEM_SLEEP );
 586     }
 587     if( p_pic == NULL )
 588         return NULL;
 589     vout_LinkPicture( p_dec->p_vout, p_pic );
 590
 591     pp_buf[0] = p_pic->p[0].p_pixels;
 592     pp_buf[1] = p_pic->p[1].p_pixels;
 593     pp_buf[2] = p_pic->p[2].p_pixels;
 594
 595     return p_pic;
 596 }