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 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Gildas Bazin <gbazin@videolan.org>
   8  *          Christophe Massiot <massiot@via.ecp.fr>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #include <vlc/vlc.h>
  29 #include <vlc_vout.h>
  30 #include <vlc_codec.h>
  31
  32 #include <mpeg2dec/mpeg2.h>
  33
  34 #include <vlc_vout_synchro.h>
  35
  36 /* Aspect ratio (ISO/IEC 13818-2 section 6.3.3, table 6-3) */
  37 #define AR_SQUARE_PICTURE       1                           /* square pixels */
  38 #define AR_4_3_PICTURE          2                        /* 4:3 picture (TV) */
  39 #define AR_16_9_PICTURE         3              /* 16:9 picture (wide screen) */
  40 #define AR_221_1_PICTURE        4                  /* 2.21:1 picture (movie) */
  41
  42 /*****************************************************************************
  43  * decoder_sys_t : libmpeg2 decoder descriptor
  44  *****************************************************************************/
  45 struct decoder_sys_t
  46 {
  47     /*
  48      * libmpeg2 properties
  49      */
  50     mpeg2dec_t          *p_mpeg2dec;
  51     const mpeg2_info_t  *p_info;
  52     vlc_bool_t          b_skip;
  53
  54     /*
  55      * Input properties
  56      */
  57     mtime_t          i_previous_pts;
  58     mtime_t          i_current_pts;
  59     mtime_t          i_previous_dts;
  60     mtime_t          i_current_dts;
  61     int              i_current_rate;
  62     picture_t *      p_picture_to_destroy;
  63     vlc_bool_t       b_garbage_pic;
  64     vlc_bool_t       b_after_sequence_header; /* is it the next frame after
  65                                                * the sequence header ?    */
  66     vlc_bool_t       b_slice_i;             /* intra-slice refresh stream */
  67     vlc_bool_t       b_second_field;
  68
  69     vlc_bool_t       b_preroll;
  70
  71     /*
  72      * Output properties
  73      */
  74     vout_synchro_t *p_synchro;
  75     int            i_aspect;
  76     int            i_sar_num;
  77     int            i_sar_den;
  78     mtime_t        i_last_frame_pts;
  79
  80 };
  81
  82 /*****************************************************************************
  83  * Local prototypes
  84  *****************************************************************************/
  85 static int  OpenDecoder( vlc_object_t * );
  86 static void CloseDecoder( vlc_object_t * );
  87
  88 static picture_t *DecodeBlock( decoder_t *, block_t ** );
  89
  90 static picture_t *GetNewPicture( decoder_t *, uint8_t ** );
  91 static void GetAR( decoder_t *p_dec );
  92
  93 /*****************************************************************************
  94  * Module descriptor
  95  *****************************************************************************/
  96 vlc_module_begin();
  97     set_description( _("MPEG I/II video decoder (using libmpeg2)") );
  98     set_capability( "decoder", 150 );
  99     set_category( CAT_INPUT );
 100     set_subcategory( SUBCAT_INPUT_VCODEC );
 101     set_callbacks( OpenDecoder, CloseDecoder );
 102     add_shortcut( "libmpeg2" );
 103 vlc_module_end();
 104
 105 /*****************************************************************************
 106  * OpenDecoder: probe the decoder and return score
 107  *****************************************************************************/
 108 static int OpenDecoder( vlc_object_t *p_this )
 109 {
 110     decoder_t *p_dec = (decoder_t*)p_this;
 111     decoder_sys_t *p_sys;
 112     uint32_t i_accel = 0;
 113
 114     if( p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','v') &&
 115         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','1') &&
 116         /* Pinnacle hardware-mpeg1 */
 117         p_dec->fmt_in.i_codec != VLC_FOURCC('P','I','M','1') &&
 118         /* ATI Video */
 119         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','2','v') &&
 120         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','2') &&
 121         p_dec->fmt_in.i_codec != VLC_FOURCC('h','d','v','2') )
 122     {
 123         return VLC_EGENERIC;
 124     }
 125
 126     /* Allocate the memory needed to store the decoder's structure */
 127     if( ( p_dec->p_sys = p_sys =
 128           (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
 129     {
 130         msg_Err( p_dec, "out of memory" );
 131         return VLC_EGENERIC;
 132     }
 133
 134     /* Initialize the thread properties */
 135     memset( p_sys, 0, sizeof(decoder_sys_t) );
 136     p_sys->p_mpeg2dec = NULL;
 137     p_sys->p_synchro  = NULL;
 138     p_sys->p_info     = NULL;
 139     p_sys->i_current_pts  = 0;
 140     p_sys->i_previous_pts = 0;
 141     p_sys->i_current_dts  = 0;
 142     p_sys->i_previous_dts = 0;
 143     p_sys->p_picture_to_destroy = NULL;
 144     p_sys->b_garbage_pic = 0;
 145     p_sys->b_slice_i  = 0;
 146     p_sys->b_second_field = 0;
 147     p_sys->b_skip     = 0;
 148     p_sys->b_preroll = VLC_FALSE;
 149
 150 #if defined( __i386__ ) || defined( __x86_64__ )
 151     if( vlc_CPU() & CPU_CAPABILITY_MMX )
 152     {
 153         i_accel |= MPEG2_ACCEL_X86_MMX;
 154     }
 155
 156     if( vlc_CPU() & CPU_CAPABILITY_3DNOW )
 157     {
 158         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 159     }
 160
 161     if( vlc_CPU() & CPU_CAPABILITY_MMXEXT )
 162     {
 163         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 164     }
 165
 166 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 167     if( vlc_CPU() & CPU_CAPABILITY_ALTIVEC )
 168     {
 169         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 170     }
 171
 172 #else
 173     /* If we do not know this CPU, trust libmpeg2's feature detection */
 174     i_accel = MPEG2_ACCEL_DETECT;
 175
 176 #endif
 177
 178     /* Set CPU acceleration features */
 179     mpeg2_accel( i_accel );
 180
 181     /* Initialize decoder */
 182     p_sys->p_mpeg2dec = mpeg2_init();
 183     if( p_sys->p_mpeg2dec == NULL)
 184     {
 185         msg_Err( p_dec, "mpeg2_init() failed" );
 186         free( p_sys );
 187         return VLC_EGENERIC;
 188     }
 189
 190     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 191
 192     p_dec->pf_decode_video = DecodeBlock;
 193
 194     return VLC_SUCCESS;
 195 }
 196
 197 /*****************************************************************************
 198  * RunDecoder: the libmpeg2 decoder
 199  *****************************************************************************/
 200 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 201 {
 202     decoder_sys_t   *p_sys = p_dec->p_sys;
 203     mpeg2_state_t   state;
 204     picture_t       *p_pic;
 205
 206     block_t *p_block;
 207
 208     if( !pp_block || !*pp_block ) return NULL;
 209
 210     p_block = *pp_block;
 211
 212     while( 1 )
 213     {
 214         state = mpeg2_parse( p_sys->p_mpeg2dec );
 215
 216         switch( state )
 217         {
 218         case STATE_BUFFER:
 219             if( !p_block->i_buffer )
 220             {
 221                 block_Release( p_block );
 222                 return NULL;
 223             }
 224
 225             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 226                                       | BLOCK_FLAG_CORRUPTED)) &&
 227                 p_sys->p_synchro &&
 228                 p_sys->p_info->sequence &&
 229                 p_sys->p_info->sequence->width != (unsigned)-1 )
 230             {
 231                 vout_SynchroReset( p_sys->p_synchro );
 232                 if( p_sys->p_info->current_fbuf != NULL
 233                     && p_sys->p_info->current_fbuf->id != NULL )
 234                 {
 235                     p_sys->b_garbage_pic = 1;
 236                     p_pic = p_sys->p_info->current_fbuf->id;
 237                 }
 238                 else
 239                 {
 240                     uint8_t *buf[3];
 241                     buf[0] = buf[1] = buf[2] = NULL;
 242                     if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 243                         break;
 244                     mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 245                     mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 246                 }
 247                 p_sys->p_picture_to_destroy = p_pic;
 248
 249                 if ( p_sys->b_slice_i )
 250                 {
 251                     vout_SynchroNewPicture( p_sys->p_synchro,
 252                         I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
 253                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 254                     vout_SynchroDecode( p_sys->p_synchro );
 255                     vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 256                 }
 257             }
 258
 259             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 260             {
 261                 p_sys->b_preroll = VLC_TRUE;
 262             }
 263             else if( p_sys->b_preroll )
 264             {
 265                 p_sys->b_preroll = VLC_FALSE;
 266                 /* Reset synchro */
 267                 vout_SynchroReset( p_sys->p_synchro );
 268             }
 269
 270 #ifdef PIC_FLAG_PTS
 271             if( p_block->i_pts )
 272             {
 273                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 274
 275 #else /* New interface */
 276             if( p_block->i_pts || p_block->i_dts )
 277             {
 278                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 279                                    (uint32_t)p_block->i_pts,
 280                                    (uint32_t)p_block->i_dts );
 281 #endif
 282                 p_sys->i_previous_pts = p_sys->i_current_pts;
 283                 p_sys->i_current_pts = p_block->i_pts;
 284                 p_sys->i_previous_dts = p_sys->i_current_dts;
 285                 p_sys->i_current_dts = p_block->i_dts;
 286             }
 287
 288             p_sys->i_current_rate = p_block->i_rate;
 289
 290             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 291                           p_block->p_buffer + p_block->i_buffer );
 292
 293             p_block->i_buffer = 0;
 294             break;
 295
 296 #ifdef STATE_SEQUENCE_MODIFIED
 297 /* FIXME - the above ifdef is always FALSE, even with libmpeg2-0.5.0
 298  * Need to improve the implementation to avoid invalid/unref pictures */
 299
 300         case STATE_SEQUENCE_MODIFIED:
 301             GetAR( p_dec );
 302             break;
 303 #endif
 304
 305         case STATE_SEQUENCE:
 306         {
 307             /* Initialize video output */
 308             uint8_t *buf[3];
 309             buf[0] = buf[1] = buf[2] = NULL;
 310
 311             GetAR( p_dec );
 312
 313             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 314
 315             /* Set the first 2 reference frames */
 316             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 317
 318             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 319             {
 320                 block_Release( p_block );
 321                 return NULL;
 322             }
 323
 324             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 325         mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 326
 327             /* This picture will never go through display_picture. */
 328             p_pic->date = 0;
 329
 330             /* For some reason, libmpeg2 will put this pic twice in
 331              * discard_picture. This can be considered a bug in libmpeg2. */
 332             p_dec->pf_picture_link( p_dec, p_pic );
 333
 334             if( p_sys->p_synchro )
 335             {
 336                 vout_SynchroRelease( p_sys->p_synchro );
 337             }
 338             p_sys->p_synchro = vout_SynchroInit( p_dec,
 339                 (uint32_t)((uint64_t)1001000000 * 27 /
 340                 p_sys->p_info->sequence->frame_period) );
 341             p_sys->b_after_sequence_header = 1;
 342         }
 343         break;
 344
 345         case STATE_PICTURE_2ND:
 346             p_sys->b_second_field = 1;
 347             break;
 348
 349         case STATE_PICTURE:
 350         {
 351             uint8_t *buf[3];
 352             mtime_t i_pts, i_dts;
 353             buf[0] = buf[1] = buf[2] = NULL;
 354
 355             if ( p_sys->b_after_sequence_header &&
 356                  ((p_sys->p_info->current_picture->flags &
 357                        PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
 358             {
 359                 /* Intra-slice refresh. Simulate a blank I picture. */
 360                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 361                 vout_SynchroNewPicture( p_sys->p_synchro,
 362                     I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
 363                     p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 364                 vout_SynchroDecode( p_sys->p_synchro );
 365                 vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 366                 p_sys->b_slice_i = 1;
 367             }
 368             p_sys->b_after_sequence_header = 0;
 369
 370 #ifdef PIC_FLAG_PTS
 371             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
 372                 ( ( p_sys->p_info->current_picture->pts ==
 373                     (uint32_t)p_sys->i_current_pts ) ?
 374                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 375             i_dts = 0;
 376
 377             /* Hack to handle demuxers which only have DTS timestamps */
 378             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 379             {
 380                 if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 381                     (p_sys->p_info->current_picture->flags &
 382                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 383                 {
 384                     i_pts = p_block->i_dts;
 385                 }
 386             }
 387             p_block->i_pts = p_block->i_dts = 0;
 388             /* End hack */
 389
 390 #else /* New interface */
 391
 392             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 393                 ( ( p_sys->p_info->current_picture->tag ==
 394                     (uint32_t)p_sys->i_current_pts ) ?
 395                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 396             i_dts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 397                 ( ( p_sys->p_info->current_picture->tag2 ==
 398                     (uint32_t)p_sys->i_current_dts ) ?
 399                   p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 400 #endif
 401
 402             /* If nb_fields == 1, it is a field picture, and it will be
 403              * followed by another field picture for which we won't call
 404              * vout_SynchroNewPicture() because this would have other
 405              * problems, so we take it into account here.
 406              * This kind of sucks, but I didn't think better. --Meuuh
 407              */
 408             vout_SynchroNewPicture( p_sys->p_synchro,
 409                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 410                 p_sys->p_info->current_picture->nb_fields == 1 ? 2 :
 411                 p_sys->p_info->current_picture->nb_fields, i_pts, i_dts,
 412                 p_sys->i_current_rate,
 413                 p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 414
 415             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 416                 !(p_sys->b_slice_i
 417                    && ((p_sys->p_info->current_picture->flags
 418                          & PIC_MASK_CODING_TYPE) == P_CODING_TYPE))
 419                    && !vout_SynchroChoose( p_sys->p_synchro,
 420                               p_sys->p_info->current_picture->flags
 421                                 & PIC_MASK_CODING_TYPE,
 422                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 423                               p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 424             {
 425                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 426                 p_sys->b_skip = 1;
 427                 vout_SynchroTrash( p_sys->p_synchro );
 428                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 429             }
 430             else
 431             {
 432                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 433                 p_sys->b_skip = 0;
 434                 vout_SynchroDecode( p_sys->p_synchro );
 435
 436                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 437                 {
 438                     block_Release( p_block );
 439                     return NULL;
 440                 }
 441
 442                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 443         mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 444             }
 445         }
 446         break;
 447
 448         case STATE_END:
 449         case STATE_SLICE:
 450             p_pic = NULL;
 451             if( p_sys->p_info->display_fbuf
 452                 && p_sys->p_info->display_fbuf->id )
 453             {
 454                 p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;
 455
 456                 vout_SynchroEnd( p_sys->p_synchro,
 457                             p_sys->p_info->display_picture->flags
 458                              & PIC_MASK_CODING_TYPE,
 459                             p_sys->b_garbage_pic );
 460                 p_sys->b_garbage_pic = 0;
 461
 462                 if ( p_sys->p_picture_to_destroy != p_pic )
 463                 {
 464                     p_pic->date = vout_SynchroDate( p_sys->p_synchro );
 465                 }
 466                 else
 467                 {
 468                     p_sys->p_picture_to_destroy = NULL;
 469                     p_pic->date = 0;
 470                 }
 471             }
 472
 473             if( p_sys->p_info->discard_fbuf &&
 474                 p_sys->p_info->discard_fbuf->id )
 475             {
 476                 p_dec->pf_picture_unlink( p_dec,
 477                                           p_sys->p_info->discard_fbuf->id );
 478             }
 479
 480             /* For still frames */
 481             if( state == STATE_END && p_pic ) p_pic->b_force = VLC_TRUE;
 482
 483             if( p_pic )
 484             {
 485                 /* Avoid frames with identical timestamps.
 486                  * Especially needed for still frames in DVD menus. */
 487                 if( p_sys->i_last_frame_pts == p_pic->date ) p_pic->date++;
 488                 p_sys->i_last_frame_pts = p_pic->date;
 489
 490                 return p_pic;
 491             }
 492
 493             break;
 494
 495         case STATE_INVALID:
 496         {
 497             uint8_t *buf[3];
 498             buf[0] = buf[1] = buf[2] = NULL;
 499
 500             msg_Warn( p_dec, "invalid picture encountered" );
 501             if ( ( p_sys->p_info->current_picture == NULL ) ||
 502                ( ( p_sys->p_info->current_picture->flags &
 503                    PIC_MASK_CODING_TYPE) != B_CODING_TYPE ) )
 504             {
 505                 if( p_sys->p_synchro ) vout_SynchroReset( p_sys->p_synchro );
 506             }
 507             mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 508             p_sys->b_skip = 1;
 509
 510             if( p_sys->p_info->current_fbuf &&
 511                 p_sys->p_info->current_fbuf->id )
 512             {
 513                 p_sys->b_garbage_pic = 1;
 514                 p_pic = p_sys->p_info->current_fbuf->id;
 515             }
 516             else if( !p_sys->p_info->sequence )
 517             {
 518                 break;
 519             }
 520             else
 521             {
 522                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 523                     break;
 524                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 525         mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 526             }
 527             p_sys->p_picture_to_destroy = p_pic;
 528
 529             memset( p_pic->p[0].p_pixels, 0,
 530                     p_sys->p_info->sequence->width
 531                      * p_sys->p_info->sequence->height );
 532             memset( p_pic->p[1].p_pixels, 0x80,
 533                     p_sys->p_info->sequence->width
 534                      * p_sys->p_info->sequence->height / 4 );
 535             memset( p_pic->p[2].p_pixels, 0x80,
 536                     p_sys->p_info->sequence->width
 537                      * p_sys->p_info->sequence->height / 4 );
 538
 539             if( p_sys->b_slice_i )
 540             {
 541                 vout_SynchroNewPicture( p_sys->p_synchro,
 542                         I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
 543                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 544                 vout_SynchroDecode( p_sys->p_synchro );
 545                 vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 546             }
 547             break;
 548         }
 549
 550         default:
 551             break;
 552         }
 553     }
 554
 555     /* Never reached */
 556     return NULL;
 557 }
 558
 559 /*****************************************************************************
 560  * CloseDecoder: libmpeg2 decoder destruction
 561  *****************************************************************************/
 562 static void CloseDecoder( vlc_object_t *p_this )
 563 {
 564     decoder_t *p_dec = (decoder_t *)p_this;
 565     decoder_sys_t *p_sys = p_dec->p_sys;
 566
 567     if( p_sys->p_synchro ) vout_SynchroRelease( p_sys->p_synchro );
 568
 569     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 570
 571     free( p_sys );
 572 }
 573
 574 /*****************************************************************************
 575  * GetNewPicture: Get a new picture from the vout and set the buf struct
 576  *****************************************************************************/
 577 static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
 578 {
 579     decoder_sys_t *p_sys = p_dec->p_sys;
 580     picture_t *p_pic;
 581
 582     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 583     p_dec->fmt_out.video.i_visible_width =
 584         p_sys->p_info->sequence->picture_width;
 585     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 586     p_dec->fmt_out.video.i_visible_height =
 587         p_sys->p_info->sequence->picture_height;
 588     p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;
 589     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 590     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 591
 592     if( p_sys->p_info->sequence->frame_period > 0 )
 593     {
 594         p_dec->fmt_out.video.i_frame_rate =
 595             (uint32_t)( (uint64_t)1001000000 * 27 /
 596                         p_sys->p_info->sequence->frame_period );
 597         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 598     }
 599
 600     p_dec->fmt_out.i_codec =
 601         ( p_sys->p_info->sequence->chroma_height <
 602           p_sys->p_info->sequence->height ) ?
 603         VLC_FOURCC('I','4','2','0') : VLC_FOURCC('I','4','2','2');
 604
 605     /* Get a new picture */
 606     p_pic = p_dec->pf_vout_buffer_new( p_dec );
 607
 608     if( p_pic == NULL ) return NULL;
 609
 610     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 611         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 612     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 613         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 614     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 615         p_sys->p_info->current_picture->nb_fields : 2;
 616
 617     p_dec->pf_picture_link( p_dec, p_pic );
 618
 619     pp_buf[0] = p_pic->p[0].p_pixels;
 620     pp_buf[1] = p_pic->p[1].p_pixels;
 621     pp_buf[2] = p_pic->p[2].p_pixels;
 622
 623     return p_pic;
 624 }
 625
 626 /*****************************************************************************
 627  * GetAR: Get aspect ratio
 628  *****************************************************************************/
 629 static void GetAR( decoder_t *p_dec )
 630 {
 631     decoder_sys_t *p_sys = p_dec->p_sys;
 632
 633     /* Check whether the input gave a particular aspect ratio */
 634     if( p_dec->fmt_in.video.i_aspect )
 635     {
 636         p_sys->i_aspect = p_dec->fmt_in.video.i_aspect;
 637         if( p_sys->i_aspect <= AR_221_1_PICTURE )
 638         switch( p_sys->i_aspect )
 639         {
 640         case AR_4_3_PICTURE:
 641             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 642             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 643             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 644             break;
 645         case AR_16_9_PICTURE:
 646             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 16 / 9;
 647             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 16;
 648             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 9;
 649             break;
 650         case AR_221_1_PICTURE:
 651             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 221 / 100;
 652             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 221;
 653             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 100;
 654             break;
 655         case AR_SQUARE_PICTURE:
 656             p_sys->i_aspect = VOUT_ASPECT_FACTOR *
 657                            p_sys->p_info->sequence->picture_width /
 658                            p_sys->p_info->sequence->picture_height;
 659             p_sys->i_sar_num = p_sys->i_sar_den = 1;
 660             break;
 661         }
 662     }
 663     else
 664     {
 665         /* Use the value provided in the MPEG sequence header */
 666         if( p_sys->p_info->sequence->pixel_height > 0 )
 667         {
 668             p_sys->i_aspect =
 669                 ((uint64_t)p_sys->p_info->sequence->picture_width) *
 670                 p_sys->p_info->sequence->pixel_width *
 671                 VOUT_ASPECT_FACTOR /
 672                 p_sys->p_info->sequence->picture_height /
 673                 p_sys->p_info->sequence->pixel_height;
 674             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 675             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 676         }
 677         else
 678         {
 679             /* Invalid aspect, assume 4:3.
 680              * This shouldn't happen and if it does it is a bug
 681              * in libmpeg2 (likely triggered by an invalid stream) */
 682             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 683             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 684             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 685         }
 686     }
 687
 688     msg_Dbg( p_dec, "%dx%d (display %d,%d), aspect %d, sar %i:%i, %u.%03u fps",
 689              p_sys->p_info->sequence->picture_width,
 690              p_sys->p_info->sequence->picture_height,
 691              p_sys->p_info->sequence->display_width,
 692              p_sys->p_info->sequence->display_height,
 693              p_sys->i_aspect, p_sys->i_sar_num, p_sys->i_sar_den,
 694              (uint32_t)((uint64_t)1001000000 * 27 /
 695                  p_sys->p_info->sequence->frame_period / 1001),
 696              (uint32_t)((uint64_t)1001000000 * 27 /
 697                  p_sys->p_info->sequence->frame_period % 1001) );
 698 }