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/decoder.h>
  31
  32 #include <mpeg2dec/mpeg2.h>
  33
  34 #include "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('V','C','R','2') &&
 120         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','2','v') &&
 121         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','2') &&
 122         p_dec->fmt_in.i_codec != VLC_FOURCC('h','d','v','2') )
 123     {
 124         return VLC_EGENERIC;
 125     }
 126
 127     /* Allocate the memory needed to store the decoder's structure */
 128     if( ( p_dec->p_sys = p_sys =
 129           (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
 130     {
 131         msg_Err( p_dec, "out of memory" );
 132         return VLC_EGENERIC;
 133     }
 134
 135     /* Initialize the thread properties */
 136     memset( p_sys, 0, sizeof(decoder_sys_t) );
 137     p_sys->p_mpeg2dec = NULL;
 138     p_sys->p_synchro  = NULL;
 139     p_sys->p_info     = NULL;
 140     p_sys->i_current_pts  = 0;
 141     p_sys->i_previous_pts = 0;
 142     p_sys->i_current_dts  = 0;
 143     p_sys->i_previous_dts = 0;
 144     p_sys->p_picture_to_destroy = NULL;
 145     p_sys->b_garbage_pic = 0;
 146     p_sys->b_slice_i  = 0;
 147     p_sys->b_second_field = 0;
 148     p_sys->b_skip     = 0;
 149     p_sys->b_preroll = VLC_FALSE;
 150
 151 #if defined( __i386__ ) || defined( __x86_64__ )
 152     if( p_dec->p_libvlc_global->i_cpu & CPU_CAPABILITY_MMX )
 153     {
 154         i_accel |= MPEG2_ACCEL_X86_MMX;
 155     }
 156
 157     if( p_dec->p_libvlc_global->i_cpu & CPU_CAPABILITY_3DNOW )
 158     {
 159         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 160     }
 161
 162     if( p_dec->p_libvlc_global->i_cpu & CPU_CAPABILITY_MMXEXT )
 163     {
 164         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 165     }
 166
 167 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 168     if( p_dec->p_libvlc_global->i_cpu & CPU_CAPABILITY_ALTIVEC )
 169     {
 170         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 171     }
 172
 173 #else
 174     /* If we do not know this CPU, trust libmpeg2's feature detection */
 175     i_accel = MPEG2_ACCEL_DETECT;
 176
 177 #endif
 178
 179     /* Set CPU acceleration features */
 180     mpeg2_accel( i_accel );
 181
 182     /* Initialize decoder */
 183     p_sys->p_mpeg2dec = mpeg2_init();
 184     if( p_sys->p_mpeg2dec == NULL)
 185     {
 186         msg_Err( p_dec, "mpeg2_init() failed" );
 187         free( p_sys );
 188         return VLC_EGENERIC;
 189     }
 190
 191     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 192
 193     p_dec->pf_decode_video = DecodeBlock;
 194
 195     return VLC_SUCCESS;
 196 }
 197
 198 /*****************************************************************************
 199  * RunDecoder: the libmpeg2 decoder
 200  *****************************************************************************/
 201 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 202 {
 203     decoder_sys_t   *p_sys = p_dec->p_sys;
 204     mpeg2_state_t   state;
 205     picture_t       *p_pic;
 206
 207     block_t *p_block;
 208
 209     if( !pp_block || !*pp_block ) return NULL;
 210
 211     p_block = *pp_block;
 212
 213     while( 1 )
 214     {
 215         state = mpeg2_parse( p_sys->p_mpeg2dec );
 216
 217         switch( state )
 218         {
 219         case STATE_BUFFER:
 220             if( !p_block->i_buffer )
 221             {
 222                 block_Release( p_block );
 223                 return NULL;
 224             }
 225
 226             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 227                                       | BLOCK_FLAG_CORRUPTED)) &&
 228                 p_sys->p_synchro &&
 229                 p_sys->p_info->sequence &&
 230                 p_sys->p_info->sequence->width != (unsigned)-1 )
 231             {
 232                 vout_SynchroReset( p_sys->p_synchro );
 233                 if( p_sys->p_info->current_fbuf != NULL
 234                     && p_sys->p_info->current_fbuf->id != NULL )
 235                 {
 236                     p_sys->b_garbage_pic = 1;
 237                     p_pic = p_sys->p_info->current_fbuf->id;
 238                 }
 239                 else
 240                 {
 241                     uint8_t *buf[3];
 242                     buf[0] = buf[1] = buf[2] = NULL;
 243                     if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 244                         break;
 245                     mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 246                     mpeg2_stride( p_sys->p_mpeg2dec, p_pic->format.i_width );
 247                 }
 248                 p_sys->p_picture_to_destroy = p_pic;
 249
 250                 if ( p_sys->b_slice_i )
 251                 {
 252                     vout_SynchroNewPicture( p_sys->p_synchro,
 253                         I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
 254                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 255                     vout_SynchroDecode( p_sys->p_synchro );
 256                     vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 257                 }
 258             }
 259
 260             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 261             {
 262                 p_sys->b_preroll = VLC_TRUE;
 263             }
 264             else if( p_sys->b_preroll )
 265             {
 266                 p_sys->b_preroll = VLC_FALSE;
 267                 /* Reset synchro */
 268                 vout_SynchroReset( p_sys->p_synchro );
 269             }
 270
 271 #ifdef PIC_FLAG_PTS
 272             if( p_block->i_pts )
 273             {
 274                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 275
 276 #else /* New interface */
 277             if( p_block->i_pts || p_block->i_dts )
 278             {
 279                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 280                                    (uint32_t)p_block->i_pts,
 281                                    (uint32_t)p_block->i_dts );
 282 #endif
 283                 p_sys->i_previous_pts = p_sys->i_current_pts;
 284                 p_sys->i_current_pts = p_block->i_pts;
 285                 p_sys->i_previous_dts = p_sys->i_current_dts;
 286                 p_sys->i_current_dts = p_block->i_dts;
 287             }
 288
 289             p_sys->i_current_rate = p_block->i_rate;
 290
 291             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 292                           p_block->p_buffer + p_block->i_buffer );
 293
 294             p_block->i_buffer = 0;
 295             break;
 296
 297 #ifdef STATE_SEQUENCE_MODIFIED
 298         case STATE_SEQUENCE_MODIFIED:
 299             GetAR( p_dec );
 300             break;
 301 #endif
 302
 303         case STATE_SEQUENCE:
 304         {
 305             /* Initialize video output */
 306             uint8_t *buf[3];
 307             buf[0] = buf[1] = buf[2] = NULL;
 308
 309             GetAR( p_dec );
 310
 311             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 312
 313             /* Set the first 2 reference frames */
 314             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 315
 316             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 317             {
 318                 block_Release( p_block );
 319                 return NULL;
 320             }
 321
 322             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 323             mpeg2_stride( p_sys->p_mpeg2dec, p_pic->format.i_width );
 324
 325             /* This picture will never go through display_picture. */
 326             p_pic->date = 0;
 327
 328             /* For some reason, libmpeg2 will put this pic twice in
 329              * discard_picture. This can be considered a bug in libmpeg2. */
 330             p_dec->pf_picture_link( p_dec, p_pic );
 331
 332             if( p_sys->p_synchro )
 333             {
 334                 vout_SynchroRelease( p_sys->p_synchro );
 335             }
 336             p_sys->p_synchro = vout_SynchroInit( p_dec,
 337                 (uint32_t)((uint64_t)1001000000 * 27 /
 338                 p_sys->p_info->sequence->frame_period) );
 339             p_sys->b_after_sequence_header = 1;
 340         }
 341         break;
 342
 343         case STATE_PICTURE_2ND:
 344             p_sys->b_second_field = 1;
 345             break;
 346
 347         case STATE_PICTURE:
 348         {
 349             uint8_t *buf[3];
 350             mtime_t i_pts, i_dts;
 351             buf[0] = buf[1] = buf[2] = NULL;
 352
 353             if ( p_sys->b_after_sequence_header &&
 354                  ((p_sys->p_info->current_picture->flags &
 355                        PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
 356             {
 357                 /* Intra-slice refresh. Simulate a blank I picture. */
 358                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 359                 vout_SynchroNewPicture( p_sys->p_synchro,
 360                     I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
 361                     p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 362                 vout_SynchroDecode( p_sys->p_synchro );
 363                 vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 364                 p_sys->b_slice_i = 1;
 365             }
 366             p_sys->b_after_sequence_header = 0;
 367
 368 #ifdef PIC_FLAG_PTS
 369             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
 370                 ( ( p_sys->p_info->current_picture->pts ==
 371                     (uint32_t)p_sys->i_current_pts ) ?
 372                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 373             i_dts = 0;
 374
 375             /* Hack to handle demuxers which only have DTS timestamps */
 376             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 377             {
 378                 if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 379                     (p_sys->p_info->current_picture->flags &
 380                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 381                 {
 382                     i_pts = p_block->i_dts;
 383                 }
 384             }
 385             p_block->i_pts = p_block->i_dts = 0;
 386             /* End hack */
 387
 388 #else /* New interface */
 389
 390             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 391                 ( ( p_sys->p_info->current_picture->tag ==
 392                     (uint32_t)p_sys->i_current_pts ) ?
 393                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 394             i_dts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 395                 ( ( p_sys->p_info->current_picture->tag2 ==
 396                     (uint32_t)p_sys->i_current_dts ) ?
 397                   p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 398 #endif
 399
 400             /* If nb_fields == 1, it is a field picture, and it will be
 401              * followed by another field picture for which we won't call
 402              * vout_SynchroNewPicture() because this would have other
 403              * problems, so we take it into account here.
 404              * This kind of sucks, but I didn't think better. --Meuuh
 405              */
 406             vout_SynchroNewPicture( p_sys->p_synchro,
 407                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 408                 p_sys->p_info->current_picture->nb_fields == 1 ? 2 :
 409                 p_sys->p_info->current_picture->nb_fields, i_pts, i_dts,
 410                 p_sys->i_current_rate,
 411                 p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 412
 413             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 414                 !(p_sys->b_slice_i
 415                    && ((p_sys->p_info->current_picture->flags
 416                          & PIC_MASK_CODING_TYPE) == P_CODING_TYPE))
 417                    && !vout_SynchroChoose( p_sys->p_synchro,
 418                               p_sys->p_info->current_picture->flags
 419                                 & PIC_MASK_CODING_TYPE,
 420                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 421                               p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 422             {
 423                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 424                 p_sys->b_skip = 1;
 425                 vout_SynchroTrash( p_sys->p_synchro );
 426                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 427             }
 428             else
 429             {
 430                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 431                 p_sys->b_skip = 0;
 432                 vout_SynchroDecode( p_sys->p_synchro );
 433
 434                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 435                 {
 436                     block_Release( p_block );
 437                     return NULL;
 438                 }
 439
 440                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 441                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->format.i_width );
 442             }
 443         }
 444         break;
 445
 446         case STATE_END:
 447         case STATE_SLICE:
 448             p_pic = NULL;
 449             if( p_sys->p_info->display_fbuf
 450                 && p_sys->p_info->display_fbuf->id )
 451             {
 452                 p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;
 453
 454                 vout_SynchroEnd( p_sys->p_synchro,
 455                             p_sys->p_info->display_picture->flags
 456                              & PIC_MASK_CODING_TYPE,
 457                             p_sys->b_garbage_pic );
 458                 p_sys->b_garbage_pic = 0;
 459
 460                 if ( p_sys->p_picture_to_destroy != p_pic )
 461                 {
 462                     p_pic->date = vout_SynchroDate( p_sys->p_synchro );
 463                 }
 464                 else
 465                 {
 466                     p_sys->p_picture_to_destroy = NULL;
 467                     p_pic->date = 0;
 468                 }
 469             }
 470
 471             if( p_sys->p_info->discard_fbuf &&
 472                 p_sys->p_info->discard_fbuf->id )
 473             {
 474                 p_dec->pf_picture_unlink( p_dec,
 475                                           p_sys->p_info->discard_fbuf->id );
 476             }
 477
 478             /* For still frames */
 479             if( state == STATE_END && p_pic ) p_pic->b_force = VLC_TRUE;
 480
 481             if( p_pic )
 482             {
 483                 /* Avoid frames with identical timestamps.
 484                  * Especially needed for still frames in DVD menus. */
 485                 if( p_sys->i_last_frame_pts == p_pic->date ) p_pic->date++;
 486                 p_sys->i_last_frame_pts = p_pic->date;
 487
 488                 return p_pic;
 489             }
 490
 491             break;
 492
 493         case STATE_INVALID:
 494         {
 495             uint8_t *buf[3];
 496             buf[0] = buf[1] = buf[2] = NULL;
 497
 498             msg_Warn( p_dec, "invalid picture encountered" );
 499             if ( ( p_sys->p_info->current_picture == NULL ) ||
 500                ( ( p_sys->p_info->current_picture->flags &
 501                    PIC_MASK_CODING_TYPE) != B_CODING_TYPE ) )
 502             {
 503                 if( p_sys->p_synchro ) vout_SynchroReset( p_sys->p_synchro );
 504             }
 505             mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 506             p_sys->b_skip = 1;
 507
 508             if( p_sys->p_info->current_fbuf &&
 509                 p_sys->p_info->current_fbuf->id )
 510             {
 511                 p_sys->b_garbage_pic = 1;
 512                 p_pic = p_sys->p_info->current_fbuf->id;
 513             }
 514             else if( !p_sys->p_info->sequence )
 515             {
 516                 break;
 517             }
 518             else
 519             {
 520                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 521                     break;
 522                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 523                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->format.i_width );
 524             }
 525             p_sys->p_picture_to_destroy = p_pic;
 526
 527             memset( p_pic->p[0].p_pixels, 0,
 528                     p_sys->p_info->sequence->width
 529                      * p_sys->p_info->sequence->height );
 530             memset( p_pic->p[1].p_pixels, 0x80,
 531                     p_sys->p_info->sequence->width
 532                      * p_sys->p_info->sequence->height / 4 );
 533             memset( p_pic->p[2].p_pixels, 0x80,
 534                     p_sys->p_info->sequence->width
 535                      * p_sys->p_info->sequence->height / 4 );
 536
 537             if( p_sys->b_slice_i )
 538             {
 539                 vout_SynchroNewPicture( p_sys->p_synchro,
 540                         I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
 541                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 542                 vout_SynchroDecode( p_sys->p_synchro );
 543                 vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 544             }
 545             break;
 546         }
 547
 548         default:
 549             break;
 550         }
 551     }
 552
 553     /* Never reached */
 554     return NULL;
 555 }
 556
 557 /*****************************************************************************
 558  * CloseDecoder: libmpeg2 decoder destruction
 559  *****************************************************************************/
 560 static void CloseDecoder( vlc_object_t *p_this )
 561 {
 562     decoder_t *p_dec = (decoder_t *)p_this;
 563     decoder_sys_t *p_sys = p_dec->p_sys;
 564
 565     if( p_sys->p_synchro ) vout_SynchroRelease( p_sys->p_synchro );
 566
 567     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 568
 569     free( p_sys );
 570 }
 571
 572 /*****************************************************************************
 573  * GetNewPicture: Get a new picture from the vout and set the buf struct
 574  *****************************************************************************/
 575 static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
 576 {
 577     decoder_sys_t *p_sys = p_dec->p_sys;
 578     picture_t *p_pic;
 579
 580     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 581     p_dec->fmt_out.video.i_visible_width =
 582         p_sys->p_info->sequence->picture_width;
 583     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 584     p_dec->fmt_out.video.i_visible_height =
 585         p_sys->p_info->sequence->picture_height;
 586     p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;
 587     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 588     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 589
 590     if( p_sys->p_info->sequence->frame_period > 0 )
 591     {
 592         p_dec->fmt_out.video.i_frame_rate =
 593             (uint32_t)( (uint64_t)1001000000 * 27 /
 594                         p_sys->p_info->sequence->frame_period );
 595         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 596     }
 597
 598     p_dec->fmt_out.i_codec =
 599         ( p_sys->p_info->sequence->chroma_height <
 600           p_sys->p_info->sequence->height ) ?
 601         VLC_FOURCC('I','4','2','0') : VLC_FOURCC('I','4','2','2');
 602
 603     /* Get a new picture */
 604     p_pic = p_dec->pf_vout_buffer_new( p_dec );
 605
 606     if( p_pic == NULL ) return NULL;
 607
 608     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 609         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 610     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 611         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 612     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 613         p_sys->p_info->current_picture->nb_fields : 2;
 614
 615     p_dec->pf_picture_link( p_dec, p_pic );
 616
 617     pp_buf[0] = p_pic->p[0].p_pixels;
 618     pp_buf[1] = p_pic->p[1].p_pixels;
 619     pp_buf[2] = p_pic->p[2].p_pixels;
 620
 621     return p_pic;
 622 }
 623
 624 /*****************************************************************************
 625  * GetAR: Get aspect ratio
 626  *****************************************************************************/
 627 static void GetAR( decoder_t *p_dec )
 628 {
 629     decoder_sys_t *p_sys = p_dec->p_sys;
 630
 631     /* Check whether the input gave a particular aspect ratio */
 632     if( p_dec->fmt_in.video.i_aspect )
 633     {
 634         p_sys->i_aspect = p_dec->fmt_in.video.i_aspect;
 635         if( p_sys->i_aspect <= AR_221_1_PICTURE )
 636         switch( p_sys->i_aspect )
 637         {
 638         case AR_4_3_PICTURE:
 639             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 640             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 641             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 642             break;
 643         case AR_16_9_PICTURE:
 644             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 16 / 9;
 645             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 16;
 646             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 9;
 647             break;
 648         case AR_221_1_PICTURE:
 649             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 221 / 100;
 650             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 221;
 651             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 100;
 652             break;
 653         case AR_SQUARE_PICTURE:
 654             p_sys->i_aspect = VOUT_ASPECT_FACTOR *
 655                            p_sys->p_info->sequence->picture_width /
 656                            p_sys->p_info->sequence->picture_height;
 657             p_sys->i_sar_num = p_sys->i_sar_den = 1;
 658             break;
 659         }
 660     }
 661     else
 662     {
 663         /* Use the value provided in the MPEG sequence header */
 664         if( p_sys->p_info->sequence->pixel_height > 0 )
 665         {
 666             p_sys->i_aspect =
 667                 ((uint64_t)p_sys->p_info->sequence->picture_width) *
 668                 p_sys->p_info->sequence->pixel_width *
 669                 VOUT_ASPECT_FACTOR /
 670                 p_sys->p_info->sequence->picture_height /
 671                 p_sys->p_info->sequence->pixel_height;
 672             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 673             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 674         }
 675         else
 676         {
 677             /* Invalid aspect, assume 4:3.
 678              * This shouldn't happen and if it does it is a bug
 679              * in libmpeg2 (likely triggered by an invalid stream) */
 680             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 681             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 682             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 683         }
 684     }
 685
 686     msg_Dbg( p_dec, "%dx%d (display %d,%d), aspect %d, sar %i:%i, %u.%03u fps",
 687              p_sys->p_info->sequence->picture_width,
 688              p_sys->p_info->sequence->picture_height,
 689              p_sys->p_info->sequence->display_width,
 690              p_sys->p_info->sequence->display_height,
 691              p_sys->i_aspect, p_sys->i_sar_num, p_sys->i_sar_den,
 692              (uint32_t)((uint64_t)1001000000 * 27 /
 693                  p_sys->p_info->sequence->frame_period / 1001),
 694              (uint32_t)((uint64_t)1001000000 * 27 /
 695                  p_sys->p_info->sequence->frame_period % 1001) );
 696 }