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_codec.h>
  35 #include <vlc_block_helper.h>
  36 #include "../codec/cc.h"
  37
  38 #include <mpeg2.h>
  39
  40 #include <vlc_codec_synchro.h>
  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     bool                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     picture_t *      p_picture_to_destroy;
  62     bool             b_garbage_pic;
  63     bool             b_after_sequence_header; /* is it the next frame after
  64                                                * the sequence header ?    */
  65     bool             b_slice_i;             /* intra-slice refresh stream */
  66     bool             b_second_field;
  67
  68     bool             b_preroll;
  69
  70     /*
  71      * Output properties
  72      */
  73     decoder_synchro_t *p_synchro;
  74     int             i_aspect;
  75     int             i_sar_num;
  76     int             i_sar_den;
  77     mtime_t         i_last_frame_pts;
  78
  79     /* Closed captioning support */
  80     uint32_t        i_cc_flags;
  81     mtime_t         i_cc_pts;
  82     mtime_t         i_cc_dts;
  83     cc_data_t       cc;
  84     uint8_t        *p_gop_user_data;
  85     uint32_t        i_gop_user_data;
  86 };
  87
  88 /*****************************************************************************
  89  * Local prototypes
  90  *****************************************************************************/
  91 static int  OpenDecoder( vlc_object_t * );
  92 static void CloseDecoder( vlc_object_t * );
  93
  94 static picture_t *DecodeBlock( decoder_t *, block_t ** );
  95 static block_t   *GetCc( decoder_t *p_dec, bool pb_present[4] );
  96
  97 static picture_t *GetNewPicture( decoder_t *, uint8_t ** );
  98 static void GetAR( decoder_t *p_dec );
  99
 100 /*****************************************************************************
 101  * Module descriptor
 102  *****************************************************************************/
 103 vlc_module_begin ()
 104     set_description( N_("MPEG I/II video decoder (using libmpeg2)") )
 105     set_capability( "decoder", 150 )
 106     set_category( CAT_INPUT )
 107     set_subcategory( SUBCAT_INPUT_VCODEC )
 108     set_callbacks( OpenDecoder, CloseDecoder )
 109     add_shortcut( "libmpeg2" )
 110 vlc_module_end ()
 111
 112 /*****************************************************************************
 113  * OpenDecoder: probe the decoder and return score
 114  *****************************************************************************/
 115 static int OpenDecoder( vlc_object_t *p_this )
 116 {
 117     decoder_t *p_dec = (decoder_t*)p_this;
 118     decoder_sys_t *p_sys;
 119     uint32_t i_accel = 0;
 120
 121     if( p_dec->fmt_in.i_codec != VLC_CODEC_MPGV )
 122         return VLC_EGENERIC;
 123
 124     /* Select onl recognized original format (standard mpeg video) */
 125     switch( p_dec->fmt_in.i_original_fourcc )
 126     {
 127     case VLC_FOURCC('m','p','g','1'):
 128     case VLC_FOURCC('m','p','g','2'):
 129     case VLC_FOURCC('m','p','g','v'):
 130     case VLC_FOURCC('P','I','M','1'):
 131     case VLC_FOURCC('h','d','v','2'):
 132         break;
 133     default:
 134         if( p_dec->fmt_in.i_original_fourcc )
 135             return VLC_EGENERIC;
 136         break;
 137     }
 138
 139     /* Allocate the memory needed to store the decoder's structure */
 140     if( ( p_dec->p_sys = p_sys = calloc( 1, sizeof(*p_sys)) ) == NULL )
 141         return VLC_ENOMEM;
 142
 143     /* Initialize the thread properties */
 144     p_sys->p_mpeg2dec = NULL;
 145     p_sys->p_synchro  = NULL;
 146     p_sys->p_info     = NULL;
 147     p_sys->i_current_pts  = 0;
 148     p_sys->i_previous_pts = 0;
 149     p_sys->i_current_dts  = 0;
 150     p_sys->i_previous_dts = 0;
 151     p_sys->p_picture_to_destroy = NULL;
 152     p_sys->b_garbage_pic = 0;
 153     p_sys->b_slice_i  = 0;
 154     p_sys->b_second_field = 0;
 155     p_sys->b_skip     = 0;
 156     p_sys->b_preroll = false;
 157
 158     p_sys->i_cc_pts = 0;
 159     p_sys->i_cc_dts = 0;
 160     p_sys->i_cc_flags = 0;
 161 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 162     p_dec->pf_get_cc = GetCc;
 163     cc_Init( &p_sys->cc );
 164 #endif
 165     p_sys->p_gop_user_data = NULL;
 166     p_sys->i_gop_user_data = 0;
 167
 168 #if defined( __i386__ ) || defined( __x86_64__ )
 169     if( vlc_CPU() & CPU_CAPABILITY_MMX )
 170     {
 171         i_accel |= MPEG2_ACCEL_X86_MMX;
 172     }
 173
 174     if( vlc_CPU() & CPU_CAPABILITY_3DNOW )
 175     {
 176         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 177     }
 178
 179     if( vlc_CPU() & CPU_CAPABILITY_MMXEXT )
 180     {
 181         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 182     }
 183
 184 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 185     if( vlc_CPU() & CPU_CAPABILITY_ALTIVEC )
 186     {
 187         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 188     }
 189
 190 #else
 191     /* If we do not know this CPU, trust libmpeg2's feature detection */
 192     i_accel = MPEG2_ACCEL_DETECT;
 193
 194 #endif
 195
 196     /* Set CPU acceleration features */
 197     mpeg2_accel( i_accel );
 198
 199     /* Initialize decoder */
 200     p_sys->p_mpeg2dec = mpeg2_init();
 201     if( p_sys->p_mpeg2dec == NULL)
 202     {
 203         msg_Err( p_dec, "mpeg2_init() failed" );
 204         free( p_sys );
 205         return VLC_EGENERIC;
 206     }
 207
 208     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 209
 210     p_dec->pf_decode_video = DecodeBlock;
 211     p_dec->fmt_out.i_cat = VIDEO_ES;
 212     p_dec->fmt_out.i_codec = 0;
 213
 214     return VLC_SUCCESS;
 215 }
 216
 217 /*****************************************************************************
 218  * RunDecoder: the libmpeg2 decoder
 219  *****************************************************************************/
 220 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 221 {
 222     decoder_sys_t   *p_sys = p_dec->p_sys;
 223     mpeg2_state_t   state;
 224     picture_t       *p_pic;
 225
 226     block_t *p_block;
 227
 228     if( !pp_block || !*pp_block ) return NULL;
 229
 230     p_block = *pp_block;
 231
 232     while( 1 )
 233     {
 234         state = mpeg2_parse( p_sys->p_mpeg2dec );
 235
 236         switch( state )
 237         {
 238         case STATE_BUFFER:
 239             if( !p_block->i_buffer )
 240             {
 241                 block_Release( p_block );
 242                 return NULL;
 243             }
 244             if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 245                                       | BLOCK_FLAG_CORRUPTED))
 246                 cc_Flush( &p_sys->cc );
 247
 248             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 249                                       | BLOCK_FLAG_CORRUPTED)) &&
 250                 p_sys->p_synchro &&
 251                 p_sys->p_info->sequence &&
 252                 p_sys->p_info->sequence->width != (unsigned)-1 )
 253             {
 254                 decoder_SynchroReset( p_sys->p_synchro );
 255                 if( p_sys->p_info->current_fbuf != NULL
 256                     && p_sys->p_info->current_fbuf->id != NULL )
 257                 {
 258                     p_sys->b_garbage_pic = 1;
 259                     p_pic = p_sys->p_info->current_fbuf->id;
 260                 }
 261                 else
 262                 {
 263                     uint8_t *buf[3];
 264                     buf[0] = buf[1] = buf[2] = NULL;
 265                     if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 266                     {
 267                         p_block->i_buffer = 0;
 268                         break;
 269                     }
 270                     mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 271                     mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 272                 }
 273                 p_sys->p_picture_to_destroy = p_pic;
 274
 275                 if ( p_sys->b_slice_i )
 276                 {
 277                     decoder_SynchroNewPicture( p_sys->p_synchro,
 278                         I_CODING_TYPE, 2, 0, 0,
 279                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 280                     decoder_SynchroDecode( p_sys->p_synchro );
 281                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 282                 }
 283             }
 284
 285             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 286             {
 287                 p_sys->b_preroll = true;
 288             }
 289             else if( p_sys->b_preroll )
 290             {
 291                 p_sys->b_preroll = false;
 292                 /* Reset synchro */
 293                 decoder_SynchroReset( p_sys->p_synchro );
 294             }
 295
 296 #ifdef PIC_FLAG_PTS
 297             if( p_block->i_pts )
 298             {
 299                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 300
 301 #else /* New interface */
 302             if( p_block->i_pts || p_block->i_dts )
 303             {
 304                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 305                                    (uint32_t)p_block->i_pts,
 306                                    (uint32_t)p_block->i_dts );
 307 #endif
 308                 p_sys->i_previous_pts = p_sys->i_current_pts;
 309                 p_sys->i_current_pts = p_block->i_pts;
 310                 p_sys->i_previous_dts = p_sys->i_current_dts;
 311                 p_sys->i_current_dts = p_block->i_dts;
 312             }
 313
 314             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 315                           p_block->p_buffer + p_block->i_buffer );
 316
 317             p_block->i_buffer = 0;
 318             break;
 319
 320 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 321
 322         case STATE_SEQUENCE_MODIFIED:
 323             GetAR( p_dec );
 324             break;
 325 #endif
 326
 327         case STATE_SEQUENCE:
 328         {
 329             /* Initialize video output */
 330             uint8_t *buf[3];
 331             buf[0] = buf[1] = buf[2] = NULL;
 332
 333             GetAR( p_dec );
 334
 335             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 336
 337             /* Set the first 2 reference frames */
 338             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 339
 340             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 341             {
 342                 block_Release( p_block );
 343                 return NULL;
 344             }
 345
 346             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 347             mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 348
 349             /* This picture will never go through display_picture. */
 350             p_pic->date = 0;
 351
 352             /* For some reason, libmpeg2 will put this pic twice in
 353              * discard_picture. This can be considered a bug in libmpeg2. */
 354             decoder_LinkPicture( p_dec, p_pic );
 355
 356             if( p_sys->p_synchro )
 357             {
 358                 decoder_SynchroRelease( p_sys->p_synchro );
 359             }
 360             p_sys->p_synchro = decoder_SynchroInit( p_dec,
 361                 (uint32_t)((uint64_t)1001000000 * 27 /
 362                 p_sys->p_info->sequence->frame_period) );
 363             p_sys->b_after_sequence_header = 1;
 364         }
 365         break;
 366
 367         case STATE_PICTURE_2ND:
 368             p_sys->b_second_field = 1;
 369             break;
 370
 371         case STATE_PICTURE:
 372         {
 373             uint8_t *buf[3];
 374             mtime_t i_pts, i_dts;
 375             buf[0] = buf[1] = buf[2] = NULL;
 376
 377             if ( p_sys->b_after_sequence_header &&
 378                  ((p_sys->p_info->current_picture->flags &
 379                        PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
 380             {
 381                 /* Intra-slice refresh. Simulate a blank I picture. */
 382                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 383                 decoder_SynchroNewPicture( p_sys->p_synchro,
 384                     I_CODING_TYPE, 2, 0, 0,
 385                     p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 386                 decoder_SynchroDecode( p_sys->p_synchro );
 387                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 388                 p_sys->b_slice_i = 1;
 389             }
 390             p_sys->b_after_sequence_header = 0;
 391
 392 #ifdef PIC_FLAG_PTS
 393             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
 394                 ( ( p_sys->p_info->current_picture->pts ==
 395                     (uint32_t)p_sys->i_current_pts ) ?
 396                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 397             i_dts = 0;
 398
 399             /* Hack to handle demuxers which only have DTS timestamps */
 400             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 401             {
 402                 if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 403                     (p_sys->p_info->current_picture->flags &
 404                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 405                 {
 406                     i_pts = p_block->i_dts;
 407                 }
 408             }
 409             p_block->i_pts = p_block->i_dts = 0;
 410             /* End hack */
 411
 412 #else /* New interface */
 413
 414             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 415                 ( ( p_sys->p_info->current_picture->tag ==
 416                     (uint32_t)p_sys->i_current_pts ) ?
 417                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 418             i_dts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 419                 ( ( p_sys->p_info->current_picture->tag2 ==
 420                     (uint32_t)p_sys->i_current_dts ) ?
 421                   p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 422 #endif
 423
 424             /* If nb_fields == 1, it is a field picture, and it will be
 425              * followed by another field picture for which we won't call
 426              * decoder_SynchroNewPicture() because this would have other
 427              * problems, so we take it into account here.
 428              * This kind of sucks, but I didn't think better. --Meuuh
 429              */
 430             decoder_SynchroNewPicture( p_sys->p_synchro,
 431                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 432                 p_sys->p_info->current_picture->nb_fields == 1 ? 2 :
 433                 p_sys->p_info->current_picture->nb_fields, i_pts, i_dts,
 434                 p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 435
 436
 437             bool b_skip = false;
 438             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 439                 !(p_sys->b_slice_i
 440                    && ((p_sys->p_info->current_picture->flags
 441                          & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P))
 442                    && !decoder_SynchroChoose( p_sys->p_synchro,
 443                               p_sys->p_info->current_picture->flags
 444                                 & PIC_MASK_CODING_TYPE,
 445                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 446                               p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 447             {
 448                 b_skip = true;
 449             }
 450
 451             p_pic = NULL;
 452             if( !b_skip )
 453                 p_pic = GetNewPicture( p_dec, buf );
 454
 455             if( b_skip || !p_pic )
 456             {
 457                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 458                 p_sys->b_skip = 1;
 459                 decoder_SynchroTrash( p_sys->p_synchro );
 460                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 461
 462                 if( !b_skip )
 463                 {
 464                     block_Release( p_block );
 465                     return NULL;
 466                 }
 467             }
 468             else
 469             {
 470                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 471                 p_sys->b_skip = 0;
 472                 decoder_SynchroDecode( p_sys->p_synchro );
 473
 474                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 475                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 476             }
 477             if( p_sys->p_info->user_data_len > 2 || p_sys->i_gop_user_data > 2 )
 478             {
 479                 p_sys->i_cc_pts = i_pts;
 480                 p_sys->i_cc_dts = i_dts;
 481                 if( (p_sys->p_info->current_picture->flags
 482                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 483                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
 484                 else if( (p_sys->p_info->current_picture->flags
 485                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 486                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
 487                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
 488
 489                 if( p_sys->i_gop_user_data > 2 )
 490                 {
 491                     /* We now have picture info for any cached user_data out of the gop */
 492                     cc_Extract( &p_sys->cc, &p_sys->p_gop_user_data[0], p_sys->i_gop_user_data );
 493                     p_sys->i_gop_user_data = 0;
 494                 }
 495
 496                 /* Extract the CC from the user_data of the picture */
 497                 if( p_sys->p_info->user_data_len > 2 )
 498                     cc_Extract( &p_sys->cc, &p_sys->p_info->user_data[0], p_sys->p_info->user_data_len );
 499             }
 500         }
 501         break;
 502
 503         case STATE_GOP:
 504             /* There can be userdata in a GOP. It needs to be remembered for the next picture. */
 505             if( p_sys->p_info->user_data_len > 2 )
 506             {
 507                 free( p_sys->p_gop_user_data );
 508                 p_sys->p_gop_user_data = calloc( p_sys->p_info->user_data_len, sizeof(uint8_t) );
 509                 if( p_sys->p_gop_user_data )
 510                 {
 511                     p_sys->i_gop_user_data = p_sys->p_info->user_data_len;
 512                     memcpy( p_sys->p_gop_user_data, p_sys->p_info->user_data, p_sys->p_info->user_data_len );
 513                 }
 514             }
 515             break;
 516
 517         case STATE_END:
 518         case STATE_SLICE:
 519             p_pic = NULL;
 520             if( p_sys->p_info->display_fbuf
 521                 && p_sys->p_info->display_fbuf->id )
 522             {
 523                 p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;
 524
 525                 decoder_SynchroEnd( p_sys->p_synchro,
 526                             p_sys->p_info->display_picture->flags
 527                              & PIC_MASK_CODING_TYPE,
 528                             p_sys->b_garbage_pic );
 529                 p_sys->b_garbage_pic = 0;
 530
 531                 if( p_sys->p_picture_to_destroy != p_pic )
 532                 {
 533                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
 534                 }
 535                 else
 536                 {
 537                     p_sys->p_picture_to_destroy = NULL;
 538                     p_pic->date = 0;
 539                 }
 540             }
 541
 542             if( p_sys->p_info->discard_fbuf &&
 543                 p_sys->p_info->discard_fbuf->id )
 544             {
 545                 decoder_UnlinkPicture( p_dec,
 546                                        p_sys->p_info->discard_fbuf->id );
 547             }
 548
 549             /* For still frames */
 550             if( state == STATE_END && p_pic ) p_pic->b_force = true;
 551
 552             if( p_pic )
 553             {
 554                 /* Avoid frames with identical timestamps.
 555                  * Especially needed for still frames in DVD menus. */
 556                 if( p_sys->i_last_frame_pts == p_pic->date ) p_pic->date++;
 557                 p_sys->i_last_frame_pts = p_pic->date;
 558
 559                 return p_pic;
 560             }
 561             break;
 562
 563         case STATE_INVALID:
 564         {
 565             uint8_t *buf[3];
 566             buf[0] = buf[1] = buf[2] = NULL;
 567
 568             msg_Warn( p_dec, "invalid picture encountered" );
 569             if ( ( p_sys->p_info->current_picture == NULL ) ||
 570                ( ( p_sys->p_info->current_picture->flags &
 571                    PIC_MASK_CODING_TYPE) != PIC_FLAG_CODING_TYPE_B ) )
 572             {
 573                 if( p_sys->p_synchro ) decoder_SynchroReset( p_sys->p_synchro );
 574             }
 575             mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 576             p_sys->b_skip = 1;
 577             cc_Flush( &p_sys->cc );
 578
 579             if( p_sys->p_info->current_fbuf &&
 580                 p_sys->p_info->current_fbuf->id )
 581             {
 582                 p_sys->b_garbage_pic = 1;
 583                 p_pic = p_sys->p_info->current_fbuf->id;
 584             }
 585             else if( !p_sys->p_info->sequence )
 586             {
 587                 break;
 588             }
 589             else
 590             {
 591                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 592                     break;
 593                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 594                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 595             }
 596             p_sys->p_picture_to_destroy = p_pic;
 597
 598             memset( p_pic->p[0].p_pixels, 0,
 599                     p_sys->p_info->sequence->width
 600                      * p_sys->p_info->sequence->height );
 601             memset( p_pic->p[1].p_pixels, 0x80,
 602                     p_sys->p_info->sequence->width
 603                      * p_sys->p_info->sequence->height / 4 );
 604             memset( p_pic->p[2].p_pixels, 0x80,
 605                     p_sys->p_info->sequence->width
 606                      * p_sys->p_info->sequence->height / 4 );
 607
 608             if( p_sys->b_slice_i )
 609             {
 610                 decoder_SynchroNewPicture( p_sys->p_synchro,
 611                         I_CODING_TYPE, 2, 0, 0,
 612                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 613                 decoder_SynchroDecode( p_sys->p_synchro );
 614                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 615             }
 616             break;
 617         }
 618
 619         default:
 620             break;
 621         }
 622     }
 623
 624     /* Never reached */
 625     return NULL;
 626 }
 627
 628 /*****************************************************************************
 629  * CloseDecoder: libmpeg2 decoder destruction
 630  *****************************************************************************/
 631 static void CloseDecoder( vlc_object_t *p_this )
 632 {
 633     decoder_t *p_dec = (decoder_t *)p_this;
 634     decoder_sys_t *p_sys = p_dec->p_sys;
 635
 636     free( p_sys->p_gop_user_data );
 637
 638     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
 639
 640     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 641
 642     free( p_sys );
 643 }
 644
 645 /*****************************************************************************
 646  * GetNewPicture: Get a new picture from the vout and set the buf struct
 647  *****************************************************************************/
 648 static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
 649 {
 650     decoder_sys_t *p_sys = p_dec->p_sys;
 651     picture_t *p_pic;
 652
 653     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 654     p_dec->fmt_out.video.i_visible_width =
 655         p_sys->p_info->sequence->picture_width;
 656     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 657     p_dec->fmt_out.video.i_visible_height =
 658         p_sys->p_info->sequence->picture_height;
 659     p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;
 660     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 661     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 662
 663     if( p_sys->p_info->sequence->frame_period > 0 )
 664     {
 665         p_dec->fmt_out.video.i_frame_rate =
 666             (uint32_t)( (uint64_t)1001000000 * 27 /
 667                         p_sys->p_info->sequence->frame_period );
 668         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 669     }
 670
 671     p_dec->fmt_out.i_codec =
 672         ( p_sys->p_info->sequence->chroma_height <
 673           p_sys->p_info->sequence->height ) ?
 674         VLC_CODEC_I420 : VLC_CODEC_I422;
 675
 676     /* Get a new picture */
 677     p_pic = decoder_NewPicture( p_dec );
 678
 679     if( p_pic == NULL ) return NULL;
 680
 681     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 682         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 683     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 684         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 685     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 686         p_sys->p_info->current_picture->nb_fields : 2;
 687
 688     decoder_LinkPicture( p_dec, p_pic );
 689
 690     pp_buf[0] = p_pic->p[0].p_pixels;
 691     pp_buf[1] = p_pic->p[1].p_pixels;
 692     pp_buf[2] = p_pic->p[2].p_pixels;
 693
 694     return p_pic;
 695 }
 696
 697 /*****************************************************************************
 698  * GetCc: Retrieves the Closed Captions for the CC decoder.
 699  *****************************************************************************/
 700 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
 701 {
 702     decoder_sys_t   *p_sys = p_dec->p_sys;
 703     block_t         *p_cc = NULL;
 704     int i;
 705
 706     for( i = 0; i < 4; i++ )
 707         pb_present[i] = p_sys->cc.pb_present[i];
 708
 709     if( p_sys->cc.i_data <= 0 )
 710         return NULL;
 711
 712     p_cc = block_New( p_dec, p_sys->cc.i_data);
 713     if( p_cc )
 714     {
 715         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
 716         p_cc->i_dts =
 717         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
 718         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);
 719     }
 720     cc_Flush( &p_sys->cc );
 721     return p_cc;
 722 }
 723
 724 /*****************************************************************************
 725  * GetAR: Get aspect ratio
 726  *****************************************************************************/
 727 static void GetAR( decoder_t *p_dec )
 728 {
 729     decoder_sys_t *p_sys = p_dec->p_sys;
 730
 731     /* Check whether the input gave a particular aspect ratio */
 732     if( p_dec->fmt_in.video.i_aspect )
 733     {
 734         p_sys->i_aspect = p_dec->fmt_in.video.i_aspect;
 735     }
 736     else
 737     {
 738         /* Use the value provided in the MPEG sequence header */
 739         if( p_sys->p_info->sequence->pixel_height > 0 )
 740         {
 741             p_sys->i_aspect =
 742                 ((uint64_t)p_sys->p_info->sequence->picture_width) *
 743                 p_sys->p_info->sequence->pixel_width *
 744                 VOUT_ASPECT_FACTOR /
 745                 p_sys->p_info->sequence->picture_height /
 746                 p_sys->p_info->sequence->pixel_height;
 747             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 748             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 749         }
 750         else
 751         {
 752             /* Invalid aspect, assume 4:3.
 753              * This shouldn't happen and if it does it is a bug
 754              * in libmpeg2 (likely triggered by an invalid stream) */
 755             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 756             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 757             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 758         }
 759     }
 760
 761     msg_Dbg( p_dec, "%dx%d (display %d,%d), aspect %d, sar %i:%i, %u.%03u fps",
 762              p_sys->p_info->sequence->picture_width,
 763              p_sys->p_info->sequence->picture_height,
 764              p_sys->p_info->sequence->display_width,
 765              p_sys->p_info->sequence->display_height,
 766              p_sys->i_aspect, p_sys->i_sar_num, p_sys->i_sar_den,
 767              (uint32_t)((uint64_t)1001000000 * 27 /
 768                  p_sys->p_info->sequence->frame_period / 1001),
 769              (uint32_t)((uint64_t)1001000000 * 27 /
 770                  p_sys->p_info->sequence->frame_period % 1001) );
 771 }