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 #include <assert.h>
  32
  33 #include <vlc_common.h>
  34 #include <vlc_plugin.h>
  35 #include <vlc_codec.h>
  36 #include <vlc_block_helper.h>
  37 #include <vlc_cpu.h>
  38 #include "../codec/cc.h"
  39
  40 #include <mpeg2.h>
  41
  42 #include <vlc_codec_synchro.h>
  43
  44 /*****************************************************************************
  45  * decoder_sys_t : libmpeg2 decoder descriptor
  46  *****************************************************************************/
  47 #define DPB_COUNT (3+1)
  48 typedef struct
  49 {
  50     picture_t *p_picture;
  51     bool      b_linked;
  52     bool      b_displayed;
  53 } picture_dpb_t;
  54
  55 struct decoder_sys_t
  56 {
  57     /*
  58      * libmpeg2 properties
  59      */
  60     mpeg2dec_t          *p_mpeg2dec;
  61     const mpeg2_info_t  *p_info;
  62     bool                b_skip;
  63
  64     /*
  65      * Input properties
  66      */
  67     mtime_t          i_previous_pts;
  68     mtime_t          i_current_pts;
  69     mtime_t          i_previous_dts;
  70     mtime_t          i_current_dts;
  71     bool             b_garbage_pic;
  72     bool             b_after_sequence_header; /* is it the next frame after
  73                                                * the sequence header ?    */
  74     bool             b_slice_i;             /* intra-slice refresh stream */
  75     bool             b_second_field;
  76
  77     bool             b_preroll;
  78
  79     /* */
  80     picture_dpb_t        p_dpb[DPB_COUNT];
  81
  82     /*
  83      * Output properties
  84      */
  85     decoder_synchro_t *p_synchro;
  86     int             i_sar_num;
  87     int             i_sar_den;
  88     mtime_t         i_last_frame_pts;
  89
  90     /* Closed captioning support */
  91     uint32_t        i_cc_flags;
  92     mtime_t         i_cc_pts;
  93     mtime_t         i_cc_dts;
  94     cc_data_t       cc;
  95     uint8_t        *p_gop_user_data;
  96     uint32_t        i_gop_user_data;
  97 };
  98
  99 /*****************************************************************************
 100  * Local prototypes
 101  *****************************************************************************/
 102 static int  OpenDecoder( vlc_object_t * );
 103 static void CloseDecoder( vlc_object_t * );
 104
 105 static picture_t *DecodeBlock( decoder_t *, block_t ** );
 106 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 107 static block_t   *GetCc( decoder_t *p_dec, bool pb_present[4] );
 108 #endif
 109
 110 static picture_t *GetNewPicture( decoder_t * );
 111 static void PutPicture( decoder_t *, picture_t * );
 112
 113 static void GetAR( decoder_t *p_dec );
 114
 115 static void Reset( decoder_t *p_dec );
 116
 117 /* */
 118 static void DpbInit( decoder_t * );
 119 static void DpbClean( decoder_t * );
 120 static picture_t *DpbNewPicture( decoder_t * );
 121 static void DpbUnlinkPicture( decoder_t *, picture_t * );
 122 static int DpbDisplayPicture( decoder_t *, picture_t * );
 123
 124 /*****************************************************************************
 125  * Module descriptor
 126  *****************************************************************************/
 127 vlc_module_begin ()
 128     set_description( N_("MPEG I/II video decoder (using libmpeg2)") )
 129     set_capability( "decoder", 150 )
 130     set_category( CAT_INPUT )
 131     set_subcategory( SUBCAT_INPUT_VCODEC )
 132     set_callbacks( OpenDecoder, CloseDecoder )
 133     add_shortcut( "libmpeg2" )
 134 vlc_module_end ()
 135
 136 /*****************************************************************************
 137  * OpenDecoder: probe the decoder and return score
 138  *****************************************************************************/
 139 static int OpenDecoder( vlc_object_t *p_this )
 140 {
 141     decoder_t *p_dec = (decoder_t*)p_this;
 142     decoder_sys_t *p_sys;
 143     uint32_t i_accel = 0;
 144
 145     if( p_dec->fmt_in.i_codec != VLC_CODEC_MPGV )
 146         return VLC_EGENERIC;
 147
 148     /* Select onl recognized original format (standard mpeg video) */
 149     switch( p_dec->fmt_in.i_original_fourcc )
 150     {
 151     case VLC_FOURCC('m','p','g','1'):
 152     case VLC_FOURCC('m','p','g','2'):
 153     case VLC_FOURCC('m','p','g','v'):
 154     case VLC_FOURCC('P','I','M','1'):
 155     case VLC_FOURCC('h','d','v','2'):
 156         break;
 157     default:
 158         if( p_dec->fmt_in.i_original_fourcc )
 159             return VLC_EGENERIC;
 160         break;
 161     }
 162
 163     /* Allocate the memory needed to store the decoder's structure */
 164     if( ( p_dec->p_sys = p_sys = calloc( 1, sizeof(*p_sys)) ) == NULL )
 165         return VLC_ENOMEM;
 166
 167     /* Initialize the thread properties */
 168     p_sys->p_mpeg2dec = NULL;
 169     p_sys->p_synchro  = NULL;
 170     p_sys->p_info     = NULL;
 171     p_sys->i_current_pts  = 0;
 172     p_sys->i_previous_pts = 0;
 173     p_sys->i_current_dts  = 0;
 174     p_sys->i_previous_dts = 0;
 175     p_sys->i_sar_num = 0;
 176     p_sys->i_sar_den = 0;
 177     p_sys->b_garbage_pic = false;
 178     p_sys->b_slice_i  = false;
 179     p_sys->b_second_field = false;
 180     p_sys->b_skip     = false;
 181     p_sys->b_preroll = false;
 182     DpbInit( p_dec );
 183
 184     p_sys->i_cc_pts = 0;
 185     p_sys->i_cc_dts = 0;
 186     p_sys->i_cc_flags = 0;
 187 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 188     p_dec->pf_get_cc = GetCc;
 189     cc_Init( &p_sys->cc );
 190 #endif
 191     p_sys->p_gop_user_data = NULL;
 192     p_sys->i_gop_user_data = 0;
 193
 194 #if defined( __i386__ ) || defined( __x86_64__ )
 195     if( vlc_CPU() & CPU_CAPABILITY_MMX )
 196     {
 197         i_accel |= MPEG2_ACCEL_X86_MMX;
 198     }
 199
 200     if( vlc_CPU() & CPU_CAPABILITY_3DNOW )
 201     {
 202         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 203     }
 204
 205     if( vlc_CPU() & CPU_CAPABILITY_MMXEXT )
 206     {
 207         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 208     }
 209
 210 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 211     if( vlc_CPU() & CPU_CAPABILITY_ALTIVEC )
 212     {
 213         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 214     }
 215
 216 #elif defined(__arm__)
 217     i_accel |= MPEG2_ACCEL_ARM;
 218
 219 # ifdef MPEG2_ACCEL_ARM_NEON
 220     if( vlc_CPU() & CPU_CAPABILITY_NEON )
 221         i_accel |= MPEG2_ACCEL_ARM_NEON;
 222 # endif
 223
 224 #else
 225     /* If we do not know this CPU, trust libmpeg2's feature detection */
 226     i_accel = MPEG2_ACCEL_DETECT;
 227
 228 #endif
 229
 230     /* Set CPU acceleration features */
 231     mpeg2_accel( i_accel );
 232
 233     /* Initialize decoder */
 234     p_sys->p_mpeg2dec = mpeg2_init();
 235     if( p_sys->p_mpeg2dec == NULL)
 236     {
 237         msg_Err( p_dec, "mpeg2_init() failed" );
 238         free( p_sys );
 239         return VLC_EGENERIC;
 240     }
 241
 242     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 243
 244     p_dec->pf_decode_video = DecodeBlock;
 245     p_dec->fmt_out.i_cat = VIDEO_ES;
 246     p_dec->fmt_out.i_codec = 0;
 247
 248     return VLC_SUCCESS;
 249 }
 250
 251 /*****************************************************************************
 252  * RunDecoder: the libmpeg2 decoder
 253  *****************************************************************************/
 254 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 255 {
 256     decoder_sys_t   *p_sys = p_dec->p_sys;
 257     mpeg2_state_t   state;
 258     picture_t       *p_pic;
 259
 260     block_t *p_block;
 261
 262     if( !pp_block || !*pp_block )
 263         return NULL;
 264
 265     p_block = *pp_block;
 266     if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY | BLOCK_FLAG_CORRUPTED) )
 267         Reset( p_dec );
 268
 269     while( 1 )
 270     {
 271         state = mpeg2_parse( p_sys->p_mpeg2dec );
 272
 273         switch( state )
 274         {
 275         case STATE_SEQUENCE:
 276         {
 277             /* */
 278             DpbClean( p_dec );
 279
 280             /* */
 281             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 282
 283             /* Set the first 2 reference frames */
 284             p_sys->i_sar_num = 0;
 285             p_sys->i_sar_den = 0;
 286             GetAR( p_dec );
 287             for( int i = 0; i < 2; i++ )
 288             {
 289                 picture_t *p_picture = DpbNewPicture( p_dec );
 290                 if( !p_picture )
 291                 {
 292                     Reset( p_dec );
 293                     block_Release( p_block );
 294                     return NULL;
 295                 }
 296                 PutPicture( p_dec, p_picture );
 297             }
 298
 299             if( p_sys->p_synchro )
 300                 decoder_SynchroRelease( p_sys->p_synchro );
 301
 302             if( p_sys->p_info->sequence->frame_period <= 0 )
 303                 p_sys->p_synchro = NULL;
 304             else
 305                 p_sys->p_synchro =
 306                 decoder_SynchroInit( p_dec, (uint32_t)(UINT64_C(1001000000) *
 307                                 27 / p_sys->p_info->sequence->frame_period) );
 308             p_sys->b_after_sequence_header = true;
 309             break;
 310         }
 311
 312         case STATE_GOP:
 313             /* There can be userdata in a GOP. It needs to be remembered for the next picture. */
 314             if( p_sys->p_info->user_data_len > 2 )
 315             {
 316                 free( p_sys->p_gop_user_data );
 317                 p_sys->p_gop_user_data = calloc( p_sys->p_info->user_data_len, sizeof(uint8_t) );
 318                 if( p_sys->p_gop_user_data )
 319                 {
 320                     p_sys->i_gop_user_data = p_sys->p_info->user_data_len;
 321                     memcpy( p_sys->p_gop_user_data, p_sys->p_info->user_data, p_sys->p_info->user_data_len );
 322                 }
 323             }
 324             break;
 325
 326         case STATE_PICTURE:
 327         {
 328             const mpeg2_info_t *p_info = p_sys->p_info;
 329             const mpeg2_picture_t *p_current = p_info->current_picture;
 330
 331             mtime_t i_pts, i_dts;
 332
 333             if( p_sys->b_after_sequence_header &&
 334                 (p_current->flags &
 335                     PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 336             {
 337                 /* Intra-slice refresh. Simulate a blank I picture. */
 338                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 339                 decoder_SynchroNewPicture( p_sys->p_synchro,
 340                                            I_CODING_TYPE, 2, 0, 0,
 341                                            p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 342                 decoder_SynchroDecode( p_sys->p_synchro );
 343                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 344                 p_sys->b_slice_i = true;
 345             }
 346             p_sys->b_after_sequence_header = false;
 347
 348 #ifdef PIC_FLAG_PTS
 349             i_pts = p_current->flags & PIC_FLAG_PTS ?
 350                 ( ( p_current->pts ==
 351                     (uint32_t)p_sys->i_current_pts ) ?
 352                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 353             i_dts = 0;
 354
 355             /* Hack to handle demuxers which only have DTS timestamps */
 356             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 357             {
 358                 if( p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 359                     (p_current->flags &
 360                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 361                 {
 362                     i_pts = p_block->i_dts;
 363                 }
 364             }
 365             p_block->i_pts = p_block->i_dts = 0;
 366             /* End hack */
 367
 368 #else /* New interface */
 369
 370             i_pts = p_current->flags & PIC_FLAG_TAGS ?
 371                 ( ( p_current->tag == (uint32_t)p_sys->i_current_pts ) ?
 372                             p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 373             i_dts = p_current->flags & PIC_FLAG_TAGS ?
 374                 ( ( p_current->tag2 == (uint32_t)p_sys->i_current_dts ) ?
 375                             p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 376 #endif
 377
 378             /* If nb_fields == 1, it is a field picture, and it will be
 379              * followed by another field picture for which we won't call
 380              * decoder_SynchroNewPicture() because this would have other
 381              * problems, so we take it into account here.
 382              * This kind of sucks, but I didn't think better. --Meuuh
 383              */
 384             decoder_SynchroNewPicture( p_sys->p_synchro,
 385                                        p_current->flags & PIC_MASK_CODING_TYPE,
 386                                        p_current->nb_fields == 1 ? 2 :
 387                                        p_current->nb_fields, i_pts, i_dts,
 388                                        p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 389
 390
 391             bool b_skip = false;
 392             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 393                 !(p_sys->b_slice_i
 394                    && ((p_current->flags
 395                          & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P))
 396                    && !decoder_SynchroChoose( p_sys->p_synchro,
 397                               p_current->flags
 398                                 & PIC_MASK_CODING_TYPE,
 399                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 400                               p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 401             {
 402                 b_skip = true;
 403             }
 404
 405             p_pic = NULL;
 406             if( !b_skip )
 407             {
 408                 p_pic = DpbNewPicture( p_dec );
 409                 if( !p_pic )
 410                 {
 411                     Reset( p_dec );
 412
 413                     p_pic = DpbNewPicture( p_dec );
 414                     if( !p_pic )
 415                     {
 416                         mpeg2_reset( p_sys->p_mpeg2dec, 1 );
 417                         block_Release( p_block );
 418                         return NULL;
 419                     }
 420                 }
 421             }
 422
 423             if( b_skip || !p_pic )
 424             {
 425                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 426                 p_sys->b_skip = true;
 427                 decoder_SynchroTrash( p_sys->p_synchro );
 428
 429                 PutPicture( p_dec, NULL );
 430
 431                 if( !b_skip )
 432                 {
 433                     block_Release( p_block );
 434                     return NULL;
 435                 }
 436             }
 437             else
 438             {
 439                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 440                 p_sys->b_skip = false;
 441                 decoder_SynchroDecode( p_sys->p_synchro );
 442
 443                 PutPicture( p_dec, p_pic );
 444             }
 445             if( p_info->user_data_len > 2 || p_sys->i_gop_user_data > 2 )
 446             {
 447                 p_sys->i_cc_pts = i_pts;
 448                 p_sys->i_cc_dts = i_dts;
 449                 if( (p_current->flags
 450                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 451                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
 452                 else if( (p_current->flags
 453                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 454                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
 455                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
 456
 457                 if( p_sys->i_gop_user_data > 2 )
 458                 {
 459                     /* We now have picture info for any cached user_data out of the gop */
 460                     cc_Extract( &p_sys->cc, &p_sys->p_gop_user_data[0], p_sys->i_gop_user_data );
 461                     p_sys->i_gop_user_data = 0;
 462                 }
 463
 464                 /* Extract the CC from the user_data of the picture */
 465                 if( p_info->user_data_len > 2 )
 466                     cc_Extract( &p_sys->cc, &p_info->user_data[0], p_info->user_data_len );
 467             }
 468         }
 469         break;
 470
 471
 472         case STATE_BUFFER:
 473             if( !p_block->i_buffer )
 474             {
 475                 block_Release( p_block );
 476                 return NULL;
 477             }
 478
 479             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 480                                       | BLOCK_FLAG_CORRUPTED)) &&
 481                 p_sys->p_synchro &&
 482                 p_sys->p_info->sequence &&
 483                 p_sys->p_info->sequence->width != (unsigned)-1 )
 484             {
 485                 decoder_SynchroReset( p_sys->p_synchro );
 486                 if( p_sys->p_info->current_fbuf != NULL &&
 487                     p_sys->p_info->current_fbuf->id != NULL )
 488                 {
 489                     p_sys->b_garbage_pic = true;
 490                 }
 491                 if( p_sys->b_slice_i )
 492                 {
 493                     decoder_SynchroNewPicture( p_sys->p_synchro,
 494                                                I_CODING_TYPE, 2, 0, 0,
 495                                                p_sys->p_info->sequence->flags &
 496                                                             SEQ_FLAG_LOW_DELAY );
 497                     decoder_SynchroDecode( p_sys->p_synchro );
 498                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 499                 }
 500             }
 501
 502             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 503             {
 504                 p_sys->b_preroll = true;
 505             }
 506             else if( p_sys->b_preroll )
 507             {
 508                 p_sys->b_preroll = false;
 509                 if( p_sys->p_synchro )
 510                     decoder_SynchroReset( p_sys->p_synchro );
 511             }
 512
 513 #ifdef PIC_FLAG_PTS
 514             if( p_block->i_pts )
 515             {
 516                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 517
 518 #else /* New interface */
 519             if( p_block->i_pts || p_block->i_dts )
 520             {
 521                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 522                                    (uint32_t)p_block->i_pts,
 523                                    (uint32_t)p_block->i_dts );
 524 #endif
 525                 p_sys->i_previous_pts = p_sys->i_current_pts;
 526                 p_sys->i_current_pts = p_block->i_pts;
 527                 p_sys->i_previous_dts = p_sys->i_current_dts;
 528                 p_sys->i_current_dts = p_block->i_dts;
 529             }
 530
 531             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 532                           p_block->p_buffer + p_block->i_buffer );
 533
 534             p_block->i_buffer = 0;
 535             break;
 536
 537 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 538
 539         case STATE_SEQUENCE_MODIFIED:
 540             GetAR( p_dec );
 541             break;
 542 #endif
 543         case STATE_PICTURE_2ND:
 544             p_sys->b_second_field = true;
 545             break;
 546
 547
 548         case STATE_INVALID_END:
 549         case STATE_END:
 550         case STATE_SLICE:
 551             p_pic = NULL;
 552             if( p_sys->p_info->display_fbuf &&
 553                 p_sys->p_info->display_fbuf->id )
 554             {
 555                 p_pic = p_sys->p_info->display_fbuf->id;
 556                 if( DpbDisplayPicture( p_dec, p_pic ) )
 557                     p_pic = NULL;
 558
 559                 decoder_SynchroEnd( p_sys->p_synchro,
 560                                     p_sys->p_info->display_picture->flags & PIC_MASK_CODING_TYPE,
 561                                     p_sys->b_garbage_pic );
 562
 563                 if( p_pic )
 564                 {
 565                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
 566                     if( p_sys->b_garbage_pic )
 567                         p_pic->date = 0; /* ??? */
 568                     p_sys->b_garbage_pic = false;
 569                 }
 570             }
 571
 572             if( p_sys->p_info->discard_fbuf &&
 573                 p_sys->p_info->discard_fbuf->id )
 574             {
 575                 DpbUnlinkPicture( p_dec, p_sys->p_info->discard_fbuf->id );
 576             }
 577
 578             /* For still frames */
 579             if( state == STATE_END && p_pic )
 580                 p_pic->b_force = true;
 581
 582             if( p_pic )
 583             {
 584                 /* Avoid frames with identical timestamps.
 585                  * Especially needed for still frames in DVD menus. */
 586                 if( p_sys->i_last_frame_pts == p_pic->date )
 587                     p_pic->date++;
 588                 p_sys->i_last_frame_pts = p_pic->date;
 589                 return p_pic;
 590             }
 591             break;
 592
 593         case STATE_INVALID:
 594         {
 595             msg_Err( p_dec, "invalid picture encountered" );
 596             /* I don't think we have anything to do, but well without
 597              * docs ... */
 598             break;
 599         }
 600
 601         default:
 602             break;
 603         }
 604     }
 605
 606     /* Never reached */
 607     return NULL;
 608 }
 609
 610 /*****************************************************************************
 611  * CloseDecoder: libmpeg2 decoder destruction
 612  *****************************************************************************/
 613 static void CloseDecoder( vlc_object_t *p_this )
 614 {
 615     decoder_t *p_dec = (decoder_t *)p_this;
 616     decoder_sys_t *p_sys = p_dec->p_sys;
 617
 618     DpbClean( p_dec );
 619
 620     free( p_sys->p_gop_user_data );
 621
 622     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
 623
 624     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 625
 626     free( p_sys );
 627 }
 628
 629 /*****************************************************************************
 630  * Reset: reset the decoder state
 631  *****************************************************************************/
 632 static void Reset( decoder_t *p_dec )
 633 {
 634     decoder_sys_t *p_sys = p_dec->p_sys;
 635
 636     cc_Flush( &p_sys->cc );
 637     mpeg2_reset( p_sys->p_mpeg2dec, 0 );
 638     DpbClean( p_dec );
 639 }
 640
 641 /*****************************************************************************
 642  * GetNewPicture: Get a new picture from the vout and set the buf struct
 643  *****************************************************************************/
 644 static picture_t *GetNewPicture( decoder_t *p_dec )
 645 {
 646     decoder_sys_t *p_sys = p_dec->p_sys;
 647     picture_t *p_pic;
 648
 649     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 650     p_dec->fmt_out.video.i_visible_width =
 651         p_sys->p_info->sequence->picture_width;
 652     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 653     p_dec->fmt_out.video.i_visible_height =
 654         p_sys->p_info->sequence->picture_height;
 655     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 656     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 657
 658     if( p_sys->p_info->sequence->frame_period > 0 )
 659     {
 660         p_dec->fmt_out.video.i_frame_rate =
 661             (uint32_t)( (uint64_t)1001000000 * 27 /
 662                         p_sys->p_info->sequence->frame_period );
 663         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 664     }
 665
 666     p_dec->fmt_out.i_codec =
 667         ( p_sys->p_info->sequence->chroma_height <
 668           p_sys->p_info->sequence->height ) ?
 669         VLC_CODEC_I420 : VLC_CODEC_I422;
 670
 671     /* Get a new picture */
 672     p_pic = decoder_NewPicture( p_dec );
 673
 674     if( p_pic == NULL )
 675         return NULL;
 676
 677     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 678         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 679     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 680         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 681     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 682         p_sys->p_info->current_picture->nb_fields : 2;
 683
 684     return p_pic;
 685 }
 686
 687 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 688 /*****************************************************************************
 689  * GetCc: Retrieves the Closed Captions for the CC decoder.
 690  *****************************************************************************/
 691 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
 692 {
 693     decoder_sys_t   *p_sys = p_dec->p_sys;
 694     block_t         *p_cc = NULL;
 695     int i;
 696
 697     for( i = 0; i < 4; i++ )
 698         pb_present[i] = p_sys->cc.pb_present[i];
 699
 700     if( p_sys->cc.i_data <= 0 )
 701         return NULL;
 702
 703     p_cc = block_New( p_dec, p_sys->cc.i_data);
 704     if( p_cc )
 705     {
 706         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
 707         p_cc->i_dts =
 708         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
 709         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);
 710     }
 711     cc_Flush( &p_sys->cc );
 712     return p_cc;
 713 }
 714 #endif
 715
 716 /*****************************************************************************
 717  * GetAR: Get aspect ratio
 718  *****************************************************************************/
 719 static void GetAR( decoder_t *p_dec )
 720 {
 721     decoder_sys_t *p_sys = p_dec->p_sys;
 722     int i_old_sar_num = p_sys->i_sar_num;
 723     int i_old_sar_den = p_sys->i_sar_den;
 724
 725     /* Check whether the input gave a particular aspect ratio */
 726     if( p_dec->fmt_in.video.i_sar_num > 0 &&
 727         p_dec->fmt_in.video.i_sar_den > 0 )
 728     {
 729         p_sys->i_sar_num = p_dec->fmt_in.video.i_sar_num;
 730         p_sys->i_sar_den = p_dec->fmt_in.video.i_sar_den;
 731     }
 732     else
 733     {
 734         /* Use the value provided in the MPEG sequence header */
 735         if( p_sys->p_info->sequence->pixel_height > 0 )
 736         {
 737             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 738             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 739         }
 740         else
 741         {
 742             /* Invalid aspect, assume 4:3.
 743              * This shouldn't happen and if it does it is a bug
 744              * in libmpeg2 (likely triggered by an invalid stream) */
 745             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 746             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 747         }
 748     }
 749
 750     if( p_sys->i_sar_num == i_old_sar_num &&
 751         p_sys->i_sar_den == i_old_sar_den )
 752         return;
 753
 754     if( p_sys->p_info->sequence->frame_period > 0 )
 755         msg_Dbg( p_dec,
 756                  "%dx%d (display %d,%d), sar %i:%i, %u.%03u fps",
 757                  p_sys->p_info->sequence->picture_width,
 758                  p_sys->p_info->sequence->picture_height,
 759                  p_sys->p_info->sequence->display_width,
 760                  p_sys->p_info->sequence->display_height,
 761                  p_sys->i_sar_num, p_sys->i_sar_den,
 762                  (uint32_t)((uint64_t)1001000000 * 27 /
 763                      p_sys->p_info->sequence->frame_period / 1001),
 764                  (uint32_t)((uint64_t)1001000000 * 27 /
 765                      p_sys->p_info->sequence->frame_period % 1001) );
 766     else
 767         msg_Dbg( p_dec, "bad frame period" );
 768 }
 769
 770 /*****************************************************************************
 771  * PutPicture: Put a picture_t in mpeg2 context
 772  *****************************************************************************/
 773 static void PutPicture( decoder_t *p_dec, picture_t *p_picture )
 774 {
 775     decoder_sys_t *p_sys = p_dec->p_sys;
 776
 777     /* */
 778     uint8_t *pp_buf[3];
 779     for( int j = 0; j < 3; j++ )
 780         pp_buf[j] = p_picture ? p_picture->p[j].p_pixels : NULL;
 781     mpeg2_set_buf( p_sys->p_mpeg2dec, pp_buf, p_picture );
 782
 783     /* Completly broken API, why the hell does it suppose
 784      * the stride of the chroma planes ! */
 785     if( p_picture )
 786         mpeg2_stride( p_sys->p_mpeg2dec, p_picture->p[Y_PLANE].i_pitch );
 787 }
 788
 789
 790 /**
 791  * Initialize a virtual Decoded Picture Buffer to workaround
 792  * libmpeg2 deficient API
 793  */
 794 static void DpbInit( decoder_t *p_dec )
 795 {
 796     decoder_sys_t *p_sys = p_dec->p_sys;
 797
 798     for( int i = 0; i < DPB_COUNT; i++ )
 799         p_sys->p_dpb[i].p_picture = NULL;
 800 }
 801 /**
 802  * Empty and reset the current DPB
 803  */
 804 static void DpbClean( decoder_t *p_dec )
 805 {
 806     decoder_sys_t *p_sys = p_dec->p_sys;
 807
 808     for( int i = 0; i < DPB_COUNT; i++ )
 809     {
 810         picture_dpb_t *p = &p_sys->p_dpb[i];
 811         if( !p->p_picture )
 812             continue;
 813         if( p->b_linked )
 814             decoder_UnlinkPicture( p_dec, p->p_picture );
 815         if( !p->b_displayed )
 816             decoder_DeletePicture( p_dec, p->p_picture );
 817
 818         p->p_picture = NULL;
 819     }
 820 }
 821 /**
 822  * Retreive a picture and reserve a place in the DPB
 823  */
 824 static picture_t *DpbNewPicture( decoder_t *p_dec )
 825 {
 826     decoder_sys_t *p_sys = p_dec->p_sys;
 827
 828     picture_dpb_t *p;
 829     int i;
 830
 831     for( i = 0; i < DPB_COUNT; i++ )
 832     {
 833         p = &p_sys->p_dpb[i];
 834         if( !p->p_picture )
 835             break;
 836     }
 837     if( i >= DPB_COUNT )
 838     {
 839         msg_Err( p_dec, "Leaking picture" );
 840         return NULL;
 841     }
 842
 843     p->p_picture = GetNewPicture( p_dec );
 844     if( p->p_picture )
 845     {
 846         decoder_LinkPicture( p_dec, p->p_picture );
 847         p->b_linked = true;
 848         p->b_displayed = false;
 849
 850         p->p_picture->date = 0;
 851     }
 852     return p->p_picture;
 853 }
 854 static picture_dpb_t *DpbFindPicture( decoder_t *p_dec, picture_t *p_picture )
 855 {
 856     decoder_sys_t *p_sys = p_dec->p_sys;
 857
 858     for( int i = 0; i < DPB_COUNT; i++ )
 859     {
 860         picture_dpb_t *p = &p_sys->p_dpb[i];
 861         if( p->p_picture == p_picture )
 862             return p;
 863     }
 864     return NULL;
 865 }
 866 /**
 867  * Unlink the provided picture and ensure that the decoder
 868  * does not own it anymore.
 869  */
 870 static void DpbUnlinkPicture( decoder_t *p_dec, picture_t *p_picture )
 871 {
 872     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 873
 874     /* XXX it is needed to workaround libmpeg2 bugs */
 875     if( !p || !p->b_linked )
 876     {
 877         msg_Err( p_dec, "DpbUnlinkPicture called on an invalid picture" );
 878         return;
 879     }
 880
 881     assert( p && p->b_linked );
 882
 883     decoder_UnlinkPicture( p_dec, p->p_picture );
 884     p->b_linked = false;
 885
 886     if( !p->b_displayed )
 887         decoder_DeletePicture( p_dec, p->p_picture );
 888     p->p_picture = NULL;
 889 }
 890 /**
 891  * Mark the provided picture as displayed.
 892  */
 893 static int DpbDisplayPicture( decoder_t *p_dec, picture_t *p_picture )
 894 {
 895     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 896
 897     /* XXX it is needed to workaround libmpeg2 bugs */
 898     if( !p || p->b_displayed || !p->b_linked )
 899     {
 900         msg_Err( p_dec, "DpbDisplayPicture called on an invalid picture" );
 901         return VLC_EGENERIC;
 902     }
 903
 904     assert( p && !p->b_displayed && p->b_linked );
 905
 906     p->b_displayed = true;
 907     return VLC_SUCCESS;
 908 }
 909
 910