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 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_vout.h>
  35 #include <vlc_codec.h>
  36 #include <vlc_block_helper.h>
  37 #include "../codec/cc.h"
  38
  39 #include <mpeg2.h>
  40
  41 #include <vlc_codec_synchro.h>
  42
  43 /*****************************************************************************
  44  * decoder_sys_t : libmpeg2 decoder descriptor
  45  *****************************************************************************/
  46 struct decoder_sys_t
  47 {
  48     /*
  49      * libmpeg2 properties
  50      */
  51     mpeg2dec_t          *p_mpeg2dec;
  52     const mpeg2_info_t  *p_info;
  53     bool                b_skip;
  54
  55     /*
  56      * Input properties
  57      */
  58     mtime_t          i_previous_pts;
  59     mtime_t          i_current_pts;
  60     mtime_t          i_previous_dts;
  61     mtime_t          i_current_dts;
  62     picture_t *      p_picture_to_destroy;
  63     bool             b_garbage_pic;
  64     bool             b_after_sequence_header; /* is it the next frame after
  65                                                * the sequence header ?    */
  66     bool             b_slice_i;             /* intra-slice refresh stream */
  67     bool             b_second_field;
  68
  69     bool             b_preroll;
  70
  71     /*
  72      * Output properties
  73      */
  74     decoder_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     /* Closed captioning support */
  81     uint32_t        i_cc_flags;
  82     mtime_t         i_cc_pts;
  83     mtime_t         i_cc_dts;
  84     cc_data_t       cc;
  85     uint8_t        *p_gop_user_data;
  86     uint32_t        i_gop_user_data;
  87 };
  88
  89 /*****************************************************************************
  90  * Local prototypes
  91  *****************************************************************************/
  92 static int  OpenDecoder( vlc_object_t * );
  93 static void CloseDecoder( vlc_object_t * );
  94
  95 static picture_t *DecodeBlock( decoder_t *, block_t ** );
  96 static block_t   *GetCc( decoder_t *p_dec, bool pb_present[4] );
  97
  98 static picture_t *GetNewPicture( decoder_t *, uint8_t ** );
  99 static void GetAR( decoder_t *p_dec );
 100
 101 /*****************************************************************************
 102  * Module descriptor
 103  *****************************************************************************/
 104 vlc_module_begin ()
 105     set_description( N_("MPEG I/II video decoder (using libmpeg2)") )
 106     set_capability( "decoder", 150 )
 107     set_category( CAT_INPUT )
 108     set_subcategory( SUBCAT_INPUT_VCODEC )
 109     set_callbacks( OpenDecoder, CloseDecoder )
 110     add_shortcut( "libmpeg2" )
 111 vlc_module_end ()
 112
 113 /*****************************************************************************
 114  * OpenDecoder: probe the decoder and return score
 115  *****************************************************************************/
 116 static int OpenDecoder( vlc_object_t *p_this )
 117 {
 118     decoder_t *p_dec = (decoder_t*)p_this;
 119     decoder_sys_t *p_sys;
 120     uint32_t i_accel = 0;
 121
 122     if( p_dec->fmt_in.i_codec != VLC_CODEC_MPGV )
 123         return VLC_EGENERIC;
 124
 125     /* Select onl recognized original format (standard mpeg video) */
 126     switch( p_dec->fmt_in.i_original_fourcc )
 127     {
 128     case VLC_FOURCC('m','p','g','1'):
 129     case VLC_FOURCC('m','p','g','2'):
 130     case VLC_FOURCC('m','p','g','v'):
 131     case VLC_FOURCC('P','I','M','1'):
 132     case VLC_FOURCC('h','d','v','2'):
 133         break;
 134     default:
 135         if( p_dec->fmt_in.i_original_fourcc )
 136             return VLC_EGENERIC;
 137         break;
 138     }
 139
 140     /* Allocate the memory needed to store the decoder's structure */
 141     if( ( p_dec->p_sys = p_sys = calloc( 1, sizeof(*p_sys)) ) == NULL )
 142         return VLC_ENOMEM;
 143
 144     /* Initialize the thread properties */
 145     p_sys->p_mpeg2dec = NULL;
 146     p_sys->p_synchro  = NULL;
 147     p_sys->p_info     = NULL;
 148     p_sys->i_current_pts  = 0;
 149     p_sys->i_previous_pts = 0;
 150     p_sys->i_current_dts  = 0;
 151     p_sys->i_previous_dts = 0;
 152     p_sys->p_picture_to_destroy = NULL;
 153     p_sys->b_garbage_pic = 0;
 154     p_sys->b_slice_i  = 0;
 155     p_sys->b_second_field = 0;
 156     p_sys->b_skip     = 0;
 157     p_sys->b_preroll = false;
 158
 159     p_sys->i_cc_pts = 0;
 160     p_sys->i_cc_dts = 0;
 161     p_sys->i_cc_flags = 0;
 162 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 163     p_dec->pf_get_cc = GetCc;
 164     cc_Init( &p_sys->cc );
 165 #endif
 166     p_sys->p_gop_user_data = NULL;
 167     p_sys->i_gop_user_data = 0;
 168
 169 #if defined( __i386__ ) || defined( __x86_64__ )
 170     if( vlc_CPU() & CPU_CAPABILITY_MMX )
 171     {
 172         i_accel |= MPEG2_ACCEL_X86_MMX;
 173     }
 174
 175     if( vlc_CPU() & CPU_CAPABILITY_3DNOW )
 176     {
 177         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 178     }
 179
 180     if( vlc_CPU() & CPU_CAPABILITY_MMXEXT )
 181     {
 182         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 183     }
 184
 185 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 186     if( vlc_CPU() & CPU_CAPABILITY_ALTIVEC )
 187     {
 188         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 189     }
 190
 191 #else
 192     /* If we do not know this CPU, trust libmpeg2's feature detection */
 193     i_accel = MPEG2_ACCEL_DETECT;
 194
 195 #endif
 196
 197     /* Set CPU acceleration features */
 198     mpeg2_accel( i_accel );
 199
 200     /* Initialize decoder */
 201     p_sys->p_mpeg2dec = mpeg2_init();
 202     if( p_sys->p_mpeg2dec == NULL)
 203     {
 204         msg_Err( p_dec, "mpeg2_init() failed" );
 205         free( p_sys );
 206         return VLC_EGENERIC;
 207     }
 208
 209     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 210
 211     p_dec->pf_decode_video = DecodeBlock;
 212     p_dec->fmt_out.i_cat = VIDEO_ES;
 213     p_dec->fmt_out.i_codec = 0;
 214
 215     return VLC_SUCCESS;
 216 }
 217
 218 /*****************************************************************************
 219  * RunDecoder: the libmpeg2 decoder
 220  *****************************************************************************/
 221 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 222 {
 223     decoder_sys_t   *p_sys = p_dec->p_sys;
 224     mpeg2_state_t   state;
 225     picture_t       *p_pic;
 226
 227     block_t *p_block;
 228
 229     if( !pp_block || !*pp_block ) return NULL;
 230
 231     p_block = *pp_block;
 232
 233     while( 1 )
 234     {
 235         state = mpeg2_parse( p_sys->p_mpeg2dec );
 236
 237         switch( state )
 238         {
 239         case STATE_BUFFER:
 240             if( !p_block->i_buffer )
 241             {
 242                 block_Release( p_block );
 243                 return NULL;
 244             }
 245             if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 246                                       | BLOCK_FLAG_CORRUPTED))
 247                 cc_Flush( &p_sys->cc );
 248
 249             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 250                                       | BLOCK_FLAG_CORRUPTED)) &&
 251                 p_sys->p_synchro &&
 252                 p_sys->p_info->sequence &&
 253                 p_sys->p_info->sequence->width != (unsigned)-1 )
 254             {
 255                 decoder_SynchroReset( p_sys->p_synchro );
 256                 if( p_sys->p_info->current_fbuf != NULL
 257                     && p_sys->p_info->current_fbuf->id != NULL )
 258                 {
 259                     p_sys->b_garbage_pic = 1;
 260                     p_pic = p_sys->p_info->current_fbuf->id;
 261                 }
 262                 else
 263                 {
 264                     uint8_t *buf[3];
 265                     buf[0] = buf[1] = buf[2] = NULL;
 266                     if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 267                     {
 268                         p_block->i_buffer = 0;
 269                         break;
 270                     }
 271                     mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 272                     mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 273                 }
 274                 p_sys->p_picture_to_destroy = p_pic;
 275
 276                 if ( p_sys->b_slice_i )
 277                 {
 278                     decoder_SynchroNewPicture( p_sys->p_synchro,
 279                         I_CODING_TYPE, 2, 0, 0,
 280                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 281                     decoder_SynchroDecode( p_sys->p_synchro );
 282                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 283                 }
 284             }
 285
 286             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 287             {
 288                 p_sys->b_preroll = true;
 289             }
 290             else if( p_sys->b_preroll )
 291             {
 292                 p_sys->b_preroll = false;
 293                 /* Reset synchro */
 294                 decoder_SynchroReset( p_sys->p_synchro );
 295             }
 296
 297 #ifdef PIC_FLAG_PTS
 298             if( p_block->i_pts )
 299             {
 300                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 301
 302 #else /* New interface */
 303             if( p_block->i_pts || p_block->i_dts )
 304             {
 305                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 306                                    (uint32_t)p_block->i_pts,
 307                                    (uint32_t)p_block->i_dts );
 308 #endif
 309                 p_sys->i_previous_pts = p_sys->i_current_pts;
 310                 p_sys->i_current_pts = p_block->i_pts;
 311                 p_sys->i_previous_dts = p_sys->i_current_dts;
 312                 p_sys->i_current_dts = p_block->i_dts;
 313             }
 314
 315             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 316                           p_block->p_buffer + p_block->i_buffer );
 317
 318             p_block->i_buffer = 0;
 319             break;
 320
 321 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 322
 323         case STATE_SEQUENCE_MODIFIED:
 324             GetAR( p_dec );
 325             break;
 326 #endif
 327
 328         case STATE_SEQUENCE:
 329         {
 330             /* Initialize video output */
 331             uint8_t *buf[3];
 332             buf[0] = buf[1] = buf[2] = NULL;
 333
 334             GetAR( p_dec );
 335
 336             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 337
 338             /* Set the first 2 reference frames */
 339             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 340
 341             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 342             {
 343                 block_Release( p_block );
 344                 return NULL;
 345             }
 346
 347             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 348             mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 349
 350             /* This picture will never go through display_picture. */
 351             p_pic->date = 0;
 352
 353             /* For some reason, libmpeg2 will put this pic twice in
 354              * discard_picture. This can be considered a bug in libmpeg2. */
 355             decoder_LinkPicture( p_dec, p_pic );
 356
 357             if( p_sys->p_synchro )
 358             {
 359                 decoder_SynchroRelease( p_sys->p_synchro );
 360             }
 361             p_sys->p_synchro = decoder_SynchroInit( p_dec,
 362                 (uint32_t)((uint64_t)1001000000 * 27 /
 363                 p_sys->p_info->sequence->frame_period) );
 364             p_sys->b_after_sequence_header = 1;
 365         }
 366         break;
 367
 368         case STATE_PICTURE_2ND:
 369             p_sys->b_second_field = 1;
 370             break;
 371
 372         case STATE_PICTURE:
 373         {
 374             uint8_t *buf[3];
 375             mtime_t i_pts, i_dts;
 376             buf[0] = buf[1] = buf[2] = NULL;
 377
 378             if ( p_sys->b_after_sequence_header &&
 379                  ((p_sys->p_info->current_picture->flags &
 380                        PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
 381             {
 382                 /* Intra-slice refresh. Simulate a blank I picture. */
 383                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 384                 decoder_SynchroNewPicture( p_sys->p_synchro,
 385                     I_CODING_TYPE, 2, 0, 0,
 386                     p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 387                 decoder_SynchroDecode( p_sys->p_synchro );
 388                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 389                 p_sys->b_slice_i = 1;
 390             }
 391             p_sys->b_after_sequence_header = 0;
 392
 393 #ifdef PIC_FLAG_PTS
 394             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
 395                 ( ( p_sys->p_info->current_picture->pts ==
 396                     (uint32_t)p_sys->i_current_pts ) ?
 397                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 398             i_dts = 0;
 399
 400             /* Hack to handle demuxers which only have DTS timestamps */
 401             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 402             {
 403                 if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 404                     (p_sys->p_info->current_picture->flags &
 405                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 406                 {
 407                     i_pts = p_block->i_dts;
 408                 }
 409             }
 410             p_block->i_pts = p_block->i_dts = 0;
 411             /* End hack */
 412
 413 #else /* New interface */
 414
 415             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 416                 ( ( p_sys->p_info->current_picture->tag ==
 417                     (uint32_t)p_sys->i_current_pts ) ?
 418                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 419             i_dts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 420                 ( ( p_sys->p_info->current_picture->tag2 ==
 421                     (uint32_t)p_sys->i_current_dts ) ?
 422                   p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 423 #endif
 424
 425             /* If nb_fields == 1, it is a field picture, and it will be
 426              * followed by another field picture for which we won't call
 427              * decoder_SynchroNewPicture() because this would have other
 428              * problems, so we take it into account here.
 429              * This kind of sucks, but I didn't think better. --Meuuh
 430              */
 431             decoder_SynchroNewPicture( p_sys->p_synchro,
 432                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 433                 p_sys->p_info->current_picture->nb_fields == 1 ? 2 :
 434                 p_sys->p_info->current_picture->nb_fields, i_pts, i_dts,
 435                 p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 436
 437
 438             bool b_skip = false;
 439             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 440                 !(p_sys->b_slice_i
 441                    && ((p_sys->p_info->current_picture->flags
 442                          & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P))
 443                    && !decoder_SynchroChoose( p_sys->p_synchro,
 444                               p_sys->p_info->current_picture->flags
 445                                 & PIC_MASK_CODING_TYPE,
 446                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 447                               p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 448             {
 449                 b_skip = true;
 450             }
 451
 452             p_pic = NULL;
 453             if( !b_skip )
 454                 p_pic = GetNewPicture( p_dec, buf );
 455
 456             if( b_skip || !p_pic )
 457             {
 458                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 459                 p_sys->b_skip = 1;
 460                 decoder_SynchroTrash( p_sys->p_synchro );
 461                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 462
 463                 if( !b_skip )
 464                 {
 465                     block_Release( p_block );
 466                     return NULL;
 467                 }
 468             }
 469             else
 470             {
 471                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 472                 p_sys->b_skip = 0;
 473                 decoder_SynchroDecode( p_sys->p_synchro );
 474
 475                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 476                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 477             }
 478             if( p_sys->p_info->user_data_len > 2 || p_sys->i_gop_user_data > 2 )
 479             {
 480                 p_sys->i_cc_pts = i_pts;
 481                 p_sys->i_cc_dts = i_dts;
 482                 if( (p_sys->p_info->current_picture->flags
 483                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 484                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
 485                 else if( (p_sys->p_info->current_picture->flags
 486                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 487                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
 488                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
 489
 490                 if( p_sys->i_gop_user_data > 2 )
 491                 {
 492                     /* We now have picture info for any cached user_data out of the gop */
 493                     cc_Extract( &p_sys->cc, &p_sys->p_gop_user_data[0], p_sys->i_gop_user_data );
 494                     p_sys->i_gop_user_data = 0;
 495                 }
 496
 497                 /* Extract the CC from the user_data of the picture */
 498                 if( p_sys->p_info->user_data_len > 2 )
 499                     cc_Extract( &p_sys->cc, &p_sys->p_info->user_data[0], p_sys->p_info->user_data_len );
 500             }
 501         }
 502         break;
 503
 504         case STATE_GOP:
 505             /* There can be userdata in a GOP. It needs to be remembered for the next picture. */
 506             if( p_sys->p_info->user_data_len > 2 )
 507             {
 508                 free( p_sys->p_gop_user_data );
 509                 p_sys->p_gop_user_data = calloc( p_sys->p_info->user_data_len, sizeof(uint8_t) );
 510                 if( p_sys->p_gop_user_data )
 511                 {
 512                     p_sys->i_gop_user_data = p_sys->p_info->user_data_len;
 513                     memcpy( p_sys->p_gop_user_data, p_sys->p_info->user_data, p_sys->p_info->user_data_len );
 514                 }
 515             }
 516             break;
 517
 518         case STATE_END:
 519         case STATE_SLICE:
 520             p_pic = NULL;
 521             if( p_sys->p_info->display_fbuf
 522                 && p_sys->p_info->display_fbuf->id )
 523             {
 524                 p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;
 525
 526                 decoder_SynchroEnd( p_sys->p_synchro,
 527                             p_sys->p_info->display_picture->flags
 528                              & PIC_MASK_CODING_TYPE,
 529                             p_sys->b_garbage_pic );
 530                 p_sys->b_garbage_pic = 0;
 531
 532                 if( p_sys->p_picture_to_destroy != p_pic )
 533                 {
 534                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
 535                 }
 536                 else
 537                 {
 538                     p_sys->p_picture_to_destroy = NULL;
 539                     p_pic->date = 0;
 540                 }
 541             }
 542
 543             if( p_sys->p_info->discard_fbuf &&
 544                 p_sys->p_info->discard_fbuf->id )
 545             {
 546                 decoder_UnlinkPicture( p_dec,
 547                                        p_sys->p_info->discard_fbuf->id );
 548             }
 549
 550             /* For still frames */
 551             if( state == STATE_END && p_pic ) p_pic->b_force = true;
 552
 553             if( p_pic )
 554             {
 555                 /* Avoid frames with identical timestamps.
 556                  * Especially needed for still frames in DVD menus. */
 557                 if( p_sys->i_last_frame_pts == p_pic->date ) p_pic->date++;
 558                 p_sys->i_last_frame_pts = p_pic->date;
 559
 560                 return p_pic;
 561             }
 562             break;
 563
 564         case STATE_INVALID:
 565         {
 566             uint8_t *buf[3];
 567             buf[0] = buf[1] = buf[2] = NULL;
 568
 569             msg_Warn( p_dec, "invalid picture encountered" );
 570             if ( ( p_sys->p_info->current_picture == NULL ) ||
 571                ( ( p_sys->p_info->current_picture->flags &
 572                    PIC_MASK_CODING_TYPE) != PIC_FLAG_CODING_TYPE_B ) )
 573             {
 574                 if( p_sys->p_synchro ) decoder_SynchroReset( p_sys->p_synchro );
 575             }
 576             mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 577             p_sys->b_skip = 1;
 578             cc_Flush( &p_sys->cc );
 579
 580             if( p_sys->p_info->current_fbuf &&
 581                 p_sys->p_info->current_fbuf->id )
 582             {
 583                 p_sys->b_garbage_pic = 1;
 584                 p_pic = p_sys->p_info->current_fbuf->id;
 585             }
 586             else if( !p_sys->p_info->sequence )
 587             {
 588                 break;
 589             }
 590             else
 591             {
 592                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 593                     break;
 594                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 595                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 596             }
 597             p_sys->p_picture_to_destroy = p_pic;
 598
 599             memset( p_pic->p[0].p_pixels, 0,
 600                     p_sys->p_info->sequence->width
 601                      * p_sys->p_info->sequence->height );
 602             memset( p_pic->p[1].p_pixels, 0x80,
 603                     p_sys->p_info->sequence->width
 604                      * p_sys->p_info->sequence->height / 4 );
 605             memset( p_pic->p[2].p_pixels, 0x80,
 606                     p_sys->p_info->sequence->width
 607                      * p_sys->p_info->sequence->height / 4 );
 608
 609             if( p_sys->b_slice_i )
 610             {
 611                 decoder_SynchroNewPicture( p_sys->p_synchro,
 612                         I_CODING_TYPE, 2, 0, 0,
 613                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 614                 decoder_SynchroDecode( p_sys->p_synchro );
 615                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 616             }
 617             break;
 618         }
 619
 620         default:
 621             break;
 622         }
 623     }
 624
 625     /* Never reached */
 626     return NULL;
 627 }
 628
 629 /*****************************************************************************
 630  * CloseDecoder: libmpeg2 decoder destruction
 631  *****************************************************************************/
 632 static void CloseDecoder( vlc_object_t *p_this )
 633 {
 634     decoder_t *p_dec = (decoder_t *)p_this;
 635     decoder_sys_t *p_sys = p_dec->p_sys;
 636
 637     free( p_sys->p_gop_user_data );
 638
 639     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
 640
 641     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 642
 643     free( p_sys );
 644 }
 645
 646 /*****************************************************************************
 647  * GetNewPicture: Get a new picture from the vout and set the buf struct
 648  *****************************************************************************/
 649 static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
 650 {
 651     decoder_sys_t *p_sys = p_dec->p_sys;
 652     picture_t *p_pic;
 653
 654     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 655     p_dec->fmt_out.video.i_visible_width =
 656         p_sys->p_info->sequence->picture_width;
 657     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 658     p_dec->fmt_out.video.i_visible_height =
 659         p_sys->p_info->sequence->picture_height;
 660     p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;
 661     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 662     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 663
 664     if( p_sys->p_info->sequence->frame_period > 0 )
 665     {
 666         p_dec->fmt_out.video.i_frame_rate =
 667             (uint32_t)( (uint64_t)1001000000 * 27 /
 668                         p_sys->p_info->sequence->frame_period );
 669         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 670     }
 671
 672     p_dec->fmt_out.i_codec =
 673         ( p_sys->p_info->sequence->chroma_height <
 674           p_sys->p_info->sequence->height ) ?
 675         VLC_CODEC_I420 : VLC_CODEC_I422;
 676
 677     /* Get a new picture */
 678     p_pic = decoder_NewPicture( p_dec );
 679
 680     if( p_pic == NULL ) return NULL;
 681
 682     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 683         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 684     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 685         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 686     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 687         p_sys->p_info->current_picture->nb_fields : 2;
 688
 689     decoder_LinkPicture( p_dec, p_pic );
 690
 691     pp_buf[0] = p_pic->p[0].p_pixels;
 692     pp_buf[1] = p_pic->p[1].p_pixels;
 693     pp_buf[2] = p_pic->p[2].p_pixels;
 694
 695     return p_pic;
 696 }
 697
 698 /*****************************************************************************
 699  * GetCc: Retrieves the Closed Captions for the CC decoder.
 700  *****************************************************************************/
 701 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
 702 {
 703     decoder_sys_t   *p_sys = p_dec->p_sys;
 704     block_t         *p_cc = NULL;
 705     int i;
 706
 707     for( i = 0; i < 4; i++ )
 708         pb_present[i] = p_sys->cc.pb_present[i];
 709
 710     if( p_sys->cc.i_data <= 0 )
 711         return NULL;
 712
 713     p_cc = block_New( p_dec, p_sys->cc.i_data);
 714     if( p_cc )
 715     {
 716         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
 717         p_cc->i_dts =
 718         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
 719         p_cc->i_flags = ( p_sys->cc.b_reorder  ? p_sys->i_cc_flags : BLOCK_FLAG_TYPE_P ) & ( BLOCK_FLAG_TYPE_I|BLOCK_FLAG_TYPE_P|BLOCK_FLAG_TYPE_B);
 720     }
 721     cc_Flush( &p_sys->cc );
 722     return p_cc;
 723 }
 724
 725 /*****************************************************************************
 726  * GetAR: Get aspect ratio
 727  *****************************************************************************/
 728 static void GetAR( decoder_t *p_dec )
 729 {
 730     decoder_sys_t *p_sys = p_dec->p_sys;
 731
 732     /* Check whether the input gave a particular aspect ratio */
 733     if( p_dec->fmt_in.video.i_aspect )
 734     {
 735         p_sys->i_aspect = p_dec->fmt_in.video.i_aspect;
 736     }
 737     else
 738     {
 739         /* Use the value provided in the MPEG sequence header */
 740         if( p_sys->p_info->sequence->pixel_height > 0 )
 741         {
 742             p_sys->i_aspect =
 743                 ((uint64_t)p_sys->p_info->sequence->picture_width) *
 744                 p_sys->p_info->sequence->pixel_width *
 745                 VOUT_ASPECT_FACTOR /
 746                 p_sys->p_info->sequence->picture_height /
 747                 p_sys->p_info->sequence->pixel_height;
 748             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 749             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 750         }
 751         else
 752         {
 753             /* Invalid aspect, assume 4:3.
 754              * This shouldn't happen and if it does it is a bug
 755              * in libmpeg2 (likely triggered by an invalid stream) */
 756             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 757             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 758             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 759         }
 760     }
 761
 762     msg_Dbg( p_dec, "%dx%d (display %d,%d), aspect %d, sar %i:%i, %u.%03u fps",
 763              p_sys->p_info->sequence->picture_width,
 764              p_sys->p_info->sequence->picture_height,
 765              p_sys->p_info->sequence->display_width,
 766              p_sys->p_info->sequence->display_height,
 767              p_sys->i_aspect, p_sys->i_sar_num, p_sys->i_sar_den,
 768              (uint32_t)((uint64_t)1001000000 * 27 /
 769                  p_sys->p_info->sequence->frame_period / 1001),
 770              (uint32_t)((uint64_t)1001000000 * 27 /
 771                  p_sys->p_info->sequence->frame_period % 1001) );
 772 }