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 VLC authors and VideoLAN
   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 it
  11  * under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * NOTA BENE: this module requires the linking against a library which is
  27  * known to require licensing under the GNU General Public License version 2
  28  * (or later). Therefore, the result of compiling this module will normally
  29  * be subject to the terms of that later license.
  30  *****************************************************************************/
  31
  32
  33 /*****************************************************************************
  34  * Preamble
  35  *****************************************************************************/
  36 #ifdef HAVE_CONFIG_H
  37 # include "config.h"
  38 #endif
  39 #include <assert.h>
  40
  41 #include <vlc_common.h>
  42 #include <vlc_plugin.h>
  43 #include <vlc_codec.h>
  44 #include <vlc_block_helper.h>
  45 #include <vlc_cpu.h>
  46 #include "../codec/cc.h"
  47
  48 #include <mpeg2.h>
  49
  50 #include <vlc_codec_synchro.h>
  51
  52 /*****************************************************************************
  53  * decoder_sys_t : libmpeg2 decoder descriptor
  54  *****************************************************************************/
  55 #define DPB_COUNT (3+1)
  56 typedef struct
  57 {
  58     picture_t *p_picture;
  59     bool      b_linked;
  60     bool      b_displayed;
  61 } picture_dpb_t;
  62
  63 struct decoder_sys_t
  64 {
  65     /*
  66      * libmpeg2 properties
  67      */
  68     mpeg2dec_t          *p_mpeg2dec;
  69     const mpeg2_info_t  *p_info;
  70     bool                b_skip;
  71
  72     /*
  73      * Input properties
  74      */
  75     mtime_t          i_previous_pts;
  76     mtime_t          i_current_pts;
  77     mtime_t          i_previous_dts;
  78     mtime_t          i_current_dts;
  79     bool             b_garbage_pic;
  80     bool             b_after_sequence_header; /* is it the next frame after
  81                                                * the sequence header ?    */
  82     bool             b_slice_i;             /* intra-slice refresh stream */
  83     bool             b_second_field;
  84
  85     bool             b_preroll;
  86
  87     /* */
  88     picture_dpb_t        p_dpb[DPB_COUNT];
  89
  90     /*
  91      * Output properties
  92      */
  93     decoder_synchro_t *p_synchro;
  94     int             i_sar_num;
  95     int             i_sar_den;
  96     mtime_t         i_last_frame_pts;
  97
  98     /* Closed captioning support */
  99     uint32_t        i_cc_flags;
 100     mtime_t         i_cc_pts;
 101     mtime_t         i_cc_dts;
 102     cc_data_t       cc;
 103     uint8_t        *p_gop_user_data;
 104     uint32_t        i_gop_user_data;
 105 };
 106
 107 /*****************************************************************************
 108  * Local prototypes
 109  *****************************************************************************/
 110 static int  OpenDecoder( vlc_object_t * );
 111 static void CloseDecoder( vlc_object_t * );
 112
 113 static picture_t *DecodeBlock( decoder_t *, block_t ** );
 114 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 115 static block_t   *GetCc( decoder_t *p_dec, bool pb_present[4] );
 116 #endif
 117
 118 static picture_t *GetNewPicture( decoder_t * );
 119 static void PutPicture( decoder_t *, picture_t * );
 120
 121 static void GetAR( decoder_t *p_dec );
 122
 123 static void Reset( decoder_t *p_dec );
 124
 125 /* */
 126 static void DpbInit( decoder_t * );
 127 static void DpbClean( decoder_t * );
 128 static picture_t *DpbNewPicture( decoder_t * );
 129 static void DpbUnlinkPicture( decoder_t *, picture_t * );
 130 static int DpbDisplayPicture( decoder_t *, picture_t * );
 131
 132 /*****************************************************************************
 133  * Module descriptor
 134  *****************************************************************************/
 135 vlc_module_begin ()
 136     set_description( N_("MPEG I/II video decoder (using libmpeg2)") )
 137     set_capability( "decoder", 50 )
 138     set_category( CAT_INPUT )
 139     set_subcategory( SUBCAT_INPUT_VCODEC )
 140     set_callbacks( OpenDecoder, CloseDecoder )
 141     add_shortcut( "libmpeg2" )
 142 vlc_module_end ()
 143
 144 /*****************************************************************************
 145  * OpenDecoder: probe the decoder and return score
 146  *****************************************************************************/
 147 static int OpenDecoder( vlc_object_t *p_this )
 148 {
 149     decoder_t *p_dec = (decoder_t*)p_this;
 150     decoder_sys_t *p_sys;
 151     uint32_t i_accel = 0;
 152
 153     if( p_dec->fmt_in.i_codec != VLC_CODEC_MPGV )
 154         return VLC_EGENERIC;
 155
 156     /* Select onl recognized original format (standard mpeg video) */
 157     switch( p_dec->fmt_in.i_original_fourcc )
 158     {
 159     case VLC_FOURCC('m','p','g','1'):
 160     case VLC_FOURCC('m','p','g','2'):
 161     case VLC_FOURCC('m','p','g','v'):
 162     case VLC_FOURCC('P','I','M','1'):
 163     case VLC_FOURCC('h','d','v','2'):
 164         break;
 165     default:
 166         if( p_dec->fmt_in.i_original_fourcc )
 167             return VLC_EGENERIC;
 168         break;
 169     }
 170
 171     /* Allocate the memory needed to store the decoder's structure */
 172     if( ( p_dec->p_sys = p_sys = calloc( 1, sizeof(*p_sys)) ) == NULL )
 173         return VLC_ENOMEM;
 174
 175     /* Initialize the thread properties */
 176     p_sys->p_mpeg2dec = NULL;
 177     p_sys->p_synchro  = NULL;
 178     p_sys->p_info     = NULL;
 179     p_sys->i_current_pts  = 0;
 180     p_sys->i_previous_pts = 0;
 181     p_sys->i_current_dts  = 0;
 182     p_sys->i_previous_dts = 0;
 183     p_sys->i_sar_num = 0;
 184     p_sys->i_sar_den = 0;
 185     p_sys->b_garbage_pic = false;
 186     p_sys->b_slice_i  = false;
 187     p_sys->b_second_field = false;
 188     p_sys->b_skip     = false;
 189     p_sys->b_preroll = false;
 190     DpbInit( p_dec );
 191
 192     p_sys->i_cc_pts = 0;
 193     p_sys->i_cc_dts = 0;
 194     p_sys->i_cc_flags = 0;
 195 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 196     p_dec->pf_get_cc = GetCc;
 197     cc_Init( &p_sys->cc );
 198 #endif
 199     p_sys->p_gop_user_data = NULL;
 200     p_sys->i_gop_user_data = 0;
 201
 202 #if defined( __i386__ ) || defined( __x86_64__ )
 203     if( vlc_CPU_MMX() )
 204         i_accel |= MPEG2_ACCEL_X86_MMX;
 205     if( vlc_CPU_3dNOW() )
 206         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 207     if( vlc_CPU_MMXEXT() )
 208         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 209 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 210     if( vlc_CPU_ALTIVEC() )
 211         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 212
 213 #elif defined(__arm__)
 214 # ifdef MPEG2_ACCEL_ARM
 215     i_accel |= MPEG2_ACCEL_ARM;
 216 # endif
 217 # ifdef MPEG2_ACCEL_ARM_NEON
 218     if( vlc_CPU_ARM_NEON() )
 219         i_accel |= MPEG2_ACCEL_ARM_NEON;
 220 # endif
 221
 222     /* TODO: sparc */
 223 #else
 224     /* If we do not know this CPU, trust libmpeg2's feature detection */
 225     i_accel = MPEG2_ACCEL_DETECT;
 226
 227 #endif
 228
 229     /* Set CPU acceleration features */
 230     mpeg2_accel( i_accel );
 231
 232     /* Initialize decoder */
 233     p_sys->p_mpeg2dec = mpeg2_init();
 234     if( p_sys->p_mpeg2dec == NULL)
 235     {
 236         msg_Err( p_dec, "mpeg2_init() failed" );
 237         free( p_sys );
 238         return VLC_EGENERIC;
 239     }
 240
 241     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 242
 243     p_dec->pf_decode_video = DecodeBlock;
 244     p_dec->fmt_out.i_cat = VIDEO_ES;
 245     p_dec->fmt_out.i_codec = 0;
 246
 247     return VLC_SUCCESS;
 248 }
 249
 250 /*****************************************************************************
 251  * RunDecoder: the libmpeg2 decoder
 252  *****************************************************************************/
 253 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 254 {
 255     decoder_sys_t   *p_sys = p_dec->p_sys;
 256     mpeg2_state_t   state;
 257     picture_t       *p_pic;
 258
 259     block_t *p_block;
 260
 261     if( !pp_block || !*pp_block )
 262         return NULL;
 263
 264     p_block = *pp_block;
 265     if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY | BLOCK_FLAG_CORRUPTED) )
 266         Reset( p_dec );
 267
 268     while( 1 )
 269     {
 270         state = mpeg2_parse( p_sys->p_mpeg2dec );
 271
 272         switch( state )
 273         {
 274         case STATE_SEQUENCE:
 275         {
 276             /* */
 277             DpbClean( p_dec );
 278
 279             /* */
 280             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 281
 282             /* Set the first 2 reference frames */
 283             p_sys->i_sar_num = 0;
 284             p_sys->i_sar_den = 0;
 285             GetAR( p_dec );
 286             for( int i = 0; i < 2; i++ )
 287             {
 288                 picture_t *p_picture = DpbNewPicture( p_dec );
 289                 if( !p_picture )
 290                 {
 291                     Reset( p_dec );
 292                     block_Release( p_block );
 293                     return NULL;
 294                 }
 295                 PutPicture( p_dec, p_picture );
 296             }
 297
 298             if( p_sys->p_synchro )
 299                 decoder_SynchroRelease( p_sys->p_synchro );
 300
 301             if( p_sys->p_info->sequence->frame_period <= 0 )
 302                 p_sys->p_synchro = NULL;
 303             else
 304                 p_sys->p_synchro =
 305                 decoder_SynchroInit( p_dec, (uint32_t)(UINT64_C(1001000000) *
 306                                 27 / p_sys->p_info->sequence->frame_period) );
 307             p_sys->b_after_sequence_header = true;
 308             break;
 309         }
 310
 311         case STATE_GOP:
 312             /* There can be userdata in a GOP. It needs to be remembered for the next picture. */
 313             if( p_sys->p_info->user_data_len > 2 )
 314             {
 315                 free( p_sys->p_gop_user_data );
 316                 p_sys->p_gop_user_data = calloc( p_sys->p_info->user_data_len, sizeof(uint8_t) );
 317                 if( p_sys->p_gop_user_data )
 318                 {
 319                     p_sys->i_gop_user_data = p_sys->p_info->user_data_len;
 320                     memcpy( p_sys->p_gop_user_data, p_sys->p_info->user_data, p_sys->p_info->user_data_len );
 321                 }
 322             }
 323             break;
 324
 325         case STATE_PICTURE:
 326         {
 327             const mpeg2_info_t *p_info = p_sys->p_info;
 328             const mpeg2_picture_t *p_current = p_info->current_picture;
 329
 330             mtime_t i_pts, i_dts;
 331
 332             if( p_sys->b_after_sequence_header &&
 333                 (p_current->flags &
 334                     PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 335             {
 336                 /* Intra-slice refresh. Simulate a blank I picture. */
 337                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 338                 decoder_SynchroNewPicture( p_sys->p_synchro,
 339                                            I_CODING_TYPE, 2, 0, 0,
 340                                            p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 341                 decoder_SynchroDecode( p_sys->p_synchro );
 342                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 343                 p_sys->b_slice_i = true;
 344             }
 345             p_sys->b_after_sequence_header = false;
 346
 347 #ifdef PIC_FLAG_PTS
 348             i_pts = p_current->flags & PIC_FLAG_PTS ?
 349                 ( ( p_current->pts ==
 350                     (uint32_t)p_sys->i_current_pts ) ?
 351                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 352             i_dts = 0;
 353
 354             /* Hack to handle demuxers which only have DTS timestamps */
 355             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 356             {
 357                 if( p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 358                     (p_current->flags &
 359                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 360                 {
 361                     i_pts = p_block->i_dts;
 362                 }
 363             }
 364             p_block->i_pts = p_block->i_dts = 0;
 365             /* End hack */
 366
 367 #else /* New interface */
 368
 369             i_pts = p_current->flags & PIC_FLAG_TAGS ?
 370                 ( ( p_current->tag == (uint32_t)p_sys->i_current_pts ) ?
 371                             p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 372             i_dts = p_current->flags & PIC_FLAG_TAGS ?
 373                 ( ( p_current->tag2 == (uint32_t)p_sys->i_current_dts ) ?
 374                             p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 375 #endif
 376
 377             /* If nb_fields == 1, it is a field picture, and it will be
 378              * followed by another field picture for which we won't call
 379              * decoder_SynchroNewPicture() because this would have other
 380              * problems, so we take it into account here.
 381              * This kind of sucks, but I didn't think better. --Meuuh
 382              */
 383             decoder_SynchroNewPicture( p_sys->p_synchro,
 384                                        p_current->flags & PIC_MASK_CODING_TYPE,
 385                                        p_current->nb_fields == 1 ? 2 :
 386                                        p_current->nb_fields, i_pts, i_dts,
 387                                        p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 388
 389
 390             bool b_skip = false;
 391             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 392                 !(p_sys->b_slice_i
 393                    && ((p_current->flags
 394                          & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P))
 395                    && !decoder_SynchroChoose( p_sys->p_synchro,
 396                               p_current->flags
 397                                 & PIC_MASK_CODING_TYPE,
 398                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 399                               p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 400             {
 401                 b_skip = true;
 402             }
 403
 404             p_pic = NULL;
 405             if( !b_skip )
 406             {
 407                 p_pic = DpbNewPicture( p_dec );
 408                 if( !p_pic )
 409                 {
 410                     Reset( p_dec );
 411
 412                     p_pic = DpbNewPicture( p_dec );
 413                     if( !p_pic )
 414                     {
 415                         mpeg2_reset( p_sys->p_mpeg2dec, 1 );
 416                         block_Release( p_block );
 417                         return NULL;
 418                     }
 419                 }
 420             }
 421
 422             if( b_skip || !p_pic )
 423             {
 424                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 425                 p_sys->b_skip = true;
 426                 decoder_SynchroTrash( p_sys->p_synchro );
 427
 428                 PutPicture( p_dec, NULL );
 429
 430                 if( !b_skip )
 431                 {
 432                     block_Release( p_block );
 433                     return NULL;
 434                 }
 435             }
 436             else
 437             {
 438                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 439                 p_sys->b_skip = false;
 440                 decoder_SynchroDecode( p_sys->p_synchro );
 441
 442                 PutPicture( p_dec, p_pic );
 443             }
 444             if( p_info->user_data_len > 2 || p_sys->i_gop_user_data > 2 )
 445             {
 446                 p_sys->i_cc_pts = i_pts;
 447                 p_sys->i_cc_dts = i_dts;
 448                 if( (p_current->flags
 449                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 450                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
 451                 else if( (p_current->flags
 452                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 453                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
 454                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
 455                 bool b_top_field_first = p_sys->p_info->current_picture->flags
 456                                            & PIC_FLAG_TOP_FIELD_FIRST;
 457
 458                 if( p_sys->i_gop_user_data > 2 )
 459                 {
 460                     /* We now have picture info for any cached user_data out of the gop */
 461                     cc_Extract( &p_sys->cc, b_top_field_first,
 462                                 &p_sys->p_gop_user_data[0], p_sys->i_gop_user_data );
 463                     p_sys->i_gop_user_data = 0;
 464                 }
 465
 466                 /* Extract the CC from the user_data of the picture */
 467                 if( p_info->user_data_len > 2 )
 468                     cc_Extract( &p_sys->cc, b_top_field_first,
 469                                 &p_info->user_data[0], p_info->user_data_len );
 470             }
 471         }
 472         break;
 473
 474
 475         case STATE_BUFFER:
 476             if( !p_block->i_buffer )
 477             {
 478                 block_Release( p_block );
 479                 return NULL;
 480             }
 481
 482             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 483                                       | BLOCK_FLAG_CORRUPTED)) &&
 484                 p_sys->p_synchro &&
 485                 p_sys->p_info->sequence &&
 486                 p_sys->p_info->sequence->width != (unsigned)-1 )
 487             {
 488                 decoder_SynchroReset( p_sys->p_synchro );
 489                 if( p_sys->p_info->current_fbuf != NULL &&
 490                     p_sys->p_info->current_fbuf->id != NULL )
 491                 {
 492                     p_sys->b_garbage_pic = true;
 493                 }
 494                 if( p_sys->b_slice_i )
 495                 {
 496                     decoder_SynchroNewPicture( p_sys->p_synchro,
 497                                                I_CODING_TYPE, 2, 0, 0,
 498                                                p_sys->p_info->sequence->flags &
 499                                                             SEQ_FLAG_LOW_DELAY );
 500                     decoder_SynchroDecode( p_sys->p_synchro );
 501                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 502                 }
 503             }
 504
 505             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 506             {
 507                 p_sys->b_preroll = true;
 508             }
 509             else if( p_sys->b_preroll )
 510             {
 511                 p_sys->b_preroll = false;
 512                 if( p_sys->p_synchro )
 513                     decoder_SynchroReset( p_sys->p_synchro );
 514             }
 515
 516 #ifdef PIC_FLAG_PTS
 517             if( p_block->i_pts )
 518             {
 519                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 520
 521 #else /* New interface */
 522             if( p_block->i_pts || p_block->i_dts )
 523             {
 524                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 525                                    (uint32_t)p_block->i_pts,
 526                                    (uint32_t)p_block->i_dts );
 527 #endif
 528                 p_sys->i_previous_pts = p_sys->i_current_pts;
 529                 p_sys->i_current_pts = p_block->i_pts;
 530                 p_sys->i_previous_dts = p_sys->i_current_dts;
 531                 p_sys->i_current_dts = p_block->i_dts;
 532             }
 533
 534             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 535                           p_block->p_buffer + p_block->i_buffer );
 536
 537             p_block->i_buffer = 0;
 538             break;
 539
 540 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 541
 542         case STATE_SEQUENCE_MODIFIED:
 543             GetAR( p_dec );
 544             break;
 545 #endif
 546         case STATE_PICTURE_2ND:
 547             p_sys->b_second_field = true;
 548             break;
 549
 550
 551         case STATE_INVALID_END:
 552         case STATE_END:
 553         case STATE_SLICE:
 554             p_pic = NULL;
 555             if( p_sys->p_info->display_fbuf &&
 556                 p_sys->p_info->display_fbuf->id )
 557             {
 558                 p_pic = p_sys->p_info->display_fbuf->id;
 559                 if( DpbDisplayPicture( p_dec, p_pic ) )
 560                     p_pic = NULL;
 561
 562                 decoder_SynchroEnd( p_sys->p_synchro,
 563                                     p_sys->p_info->display_picture->flags & PIC_MASK_CODING_TYPE,
 564                                     p_sys->b_garbage_pic );
 565
 566                 if( p_pic )
 567                 {
 568                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
 569                     if( p_sys->b_garbage_pic )
 570                         p_pic->date = 0; /* ??? */
 571                     p_sys->b_garbage_pic = false;
 572                 }
 573             }
 574
 575             if( p_sys->p_info->discard_fbuf &&
 576                 p_sys->p_info->discard_fbuf->id )
 577             {
 578                 DpbUnlinkPicture( p_dec, p_sys->p_info->discard_fbuf->id );
 579             }
 580
 581             /* For still frames */
 582             if( state == STATE_END && p_pic )
 583                 p_pic->b_force = true;
 584
 585             if( p_pic )
 586             {
 587                 /* Avoid frames with identical timestamps.
 588                  * Especially needed for still frames in DVD menus. */
 589                 if( p_sys->i_last_frame_pts == p_pic->date )
 590                     p_pic->date++;
 591                 p_sys->i_last_frame_pts = p_pic->date;
 592                 return p_pic;
 593             }
 594             break;
 595
 596         case STATE_INVALID:
 597         {
 598             msg_Err( p_dec, "invalid picture encountered" );
 599             /* I don't think we have anything to do, but well without
 600              * docs ... */
 601             break;
 602         }
 603
 604         default:
 605             break;
 606         }
 607     }
 608
 609     /* Never reached */
 610     return NULL;
 611 }
 612
 613 /*****************************************************************************
 614  * CloseDecoder: libmpeg2 decoder destruction
 615  *****************************************************************************/
 616 static void CloseDecoder( vlc_object_t *p_this )
 617 {
 618     decoder_t *p_dec = (decoder_t *)p_this;
 619     decoder_sys_t *p_sys = p_dec->p_sys;
 620
 621     DpbClean( p_dec );
 622
 623     free( p_sys->p_gop_user_data );
 624
 625     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
 626
 627     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 628
 629     free( p_sys );
 630 }
 631
 632 /*****************************************************************************
 633  * Reset: reset the decoder state
 634  *****************************************************************************/
 635 static void Reset( decoder_t *p_dec )
 636 {
 637     decoder_sys_t *p_sys = p_dec->p_sys;
 638
 639     cc_Flush( &p_sys->cc );
 640     mpeg2_reset( p_sys->p_mpeg2dec, 0 );
 641     DpbClean( p_dec );
 642 }
 643
 644 /*****************************************************************************
 645  * GetNewPicture: Get a new picture from the vout and set the buf struct
 646  *****************************************************************************/
 647 static picture_t *GetNewPicture( decoder_t *p_dec )
 648 {
 649     decoder_sys_t *p_sys = p_dec->p_sys;
 650     picture_t *p_pic;
 651
 652     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 653     p_dec->fmt_out.video.i_visible_width =
 654         p_sys->p_info->sequence->picture_width;
 655     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 656     p_dec->fmt_out.video.i_visible_height =
 657         p_sys->p_info->sequence->picture_height;
 658     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 659     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 660
 661     if( p_sys->p_info->sequence->frame_period > 0 )
 662     {
 663         p_dec->fmt_out.video.i_frame_rate =
 664             (uint32_t)( (uint64_t)1001000000 * 27 /
 665                         p_sys->p_info->sequence->frame_period );
 666         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 667     }
 668
 669     p_dec->fmt_out.i_codec =
 670         ( p_sys->p_info->sequence->chroma_height <
 671           p_sys->p_info->sequence->height ) ?
 672         VLC_CODEC_I420 : VLC_CODEC_I422;
 673
 674     /* Get a new picture */
 675     p_pic = decoder_NewPicture( p_dec );
 676
 677     if( p_pic == NULL )
 678         return NULL;
 679
 680     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 681         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 682     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 683         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 684     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 685         p_sys->p_info->current_picture->nb_fields : 2;
 686
 687     return p_pic;
 688 }
 689
 690 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 691 /*****************************************************************************
 692  * GetCc: Retrieves the Closed Captions for the CC decoder.
 693  *****************************************************************************/
 694 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
 695 {
 696     decoder_sys_t   *p_sys = p_dec->p_sys;
 697     block_t         *p_cc = NULL;
 698     int i;
 699
 700     for( i = 0; i < 4; i++ )
 701         pb_present[i] = p_sys->cc.pb_present[i];
 702
 703     if( p_sys->cc.i_data <= 0 )
 704         return NULL;
 705
 706     p_cc = block_Alloc( p_sys->cc.i_data);
 707     if( p_cc )
 708     {
 709         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
 710         p_cc->i_dts =
 711         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
 712         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);
 713     }
 714     cc_Flush( &p_sys->cc );
 715     return p_cc;
 716 }
 717 #endif
 718
 719 /*****************************************************************************
 720  * GetAR: Get aspect ratio
 721  *****************************************************************************/
 722 static void GetAR( decoder_t *p_dec )
 723 {
 724     decoder_sys_t *p_sys = p_dec->p_sys;
 725     int i_old_sar_num = p_sys->i_sar_num;
 726     int i_old_sar_den = p_sys->i_sar_den;
 727
 728     /* Check whether the input gave a particular aspect ratio */
 729     if( p_dec->fmt_in.video.i_sar_num > 0 &&
 730         p_dec->fmt_in.video.i_sar_den > 0 )
 731     {
 732         p_sys->i_sar_num = p_dec->fmt_in.video.i_sar_num;
 733         p_sys->i_sar_den = p_dec->fmt_in.video.i_sar_den;
 734     }
 735     else
 736     {
 737         /* Use the value provided in the MPEG sequence header */
 738         if( p_sys->p_info->sequence->pixel_height > 0 )
 739         {
 740             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 741             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 742         }
 743         else
 744         {
 745             /* Invalid aspect, assume 4:3.
 746              * This shouldn't happen and if it does it is a bug
 747              * in libmpeg2 (likely triggered by an invalid stream) */
 748             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 749             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 750         }
 751     }
 752
 753     if( p_sys->i_sar_num == i_old_sar_num &&
 754         p_sys->i_sar_den == i_old_sar_den )
 755         return;
 756
 757     if( p_sys->p_info->sequence->frame_period > 0 )
 758         msg_Dbg( p_dec,
 759                  "%dx%d (display %d,%d), sar %i:%i, %u.%03u fps",
 760                  p_sys->p_info->sequence->picture_width,
 761                  p_sys->p_info->sequence->picture_height,
 762                  p_sys->p_info->sequence->display_width,
 763                  p_sys->p_info->sequence->display_height,
 764                  p_sys->i_sar_num, p_sys->i_sar_den,
 765                  (uint32_t)((uint64_t)1001000000 * 27 /
 766                      p_sys->p_info->sequence->frame_period / 1001),
 767                  (uint32_t)((uint64_t)1001000000 * 27 /
 768                      p_sys->p_info->sequence->frame_period % 1001) );
 769     else
 770         msg_Dbg( p_dec, "bad frame period" );
 771 }
 772
 773 /*****************************************************************************
 774  * PutPicture: Put a picture_t in mpeg2 context
 775  *****************************************************************************/
 776 static void PutPicture( decoder_t *p_dec, picture_t *p_picture )
 777 {
 778     decoder_sys_t *p_sys = p_dec->p_sys;
 779
 780     /* */
 781     uint8_t *pp_buf[3];
 782     for( int j = 0; j < 3; j++ )
 783         pp_buf[j] = p_picture ? p_picture->p[j].p_pixels : NULL;
 784     mpeg2_set_buf( p_sys->p_mpeg2dec, pp_buf, p_picture );
 785
 786     /* Completly broken API, why the hell does it suppose
 787      * the stride of the chroma planes ! */
 788     if( p_picture )
 789         mpeg2_stride( p_sys->p_mpeg2dec, p_picture->p[Y_PLANE].i_pitch );
 790 }
 791
 792
 793 /**
 794  * Initialize a virtual Decoded Picture Buffer to workaround
 795  * libmpeg2 deficient API
 796  */
 797 static void DpbInit( decoder_t *p_dec )
 798 {
 799     decoder_sys_t *p_sys = p_dec->p_sys;
 800
 801     for( int i = 0; i < DPB_COUNT; i++ )
 802         p_sys->p_dpb[i].p_picture = NULL;
 803 }
 804 /**
 805  * Empty and reset the current DPB
 806  */
 807 static void DpbClean( decoder_t *p_dec )
 808 {
 809     decoder_sys_t *p_sys = p_dec->p_sys;
 810
 811     for( int i = 0; i < DPB_COUNT; i++ )
 812     {
 813         picture_dpb_t *p = &p_sys->p_dpb[i];
 814         if( !p->p_picture )
 815             continue;
 816         if( p->b_linked )
 817             decoder_UnlinkPicture( p_dec, p->p_picture );
 818         if( !p->b_displayed )
 819             decoder_DeletePicture( p_dec, p->p_picture );
 820
 821         p->p_picture = NULL;
 822     }
 823 }
 824 /**
 825  * Retreive a picture and reserve a place in the DPB
 826  */
 827 static picture_t *DpbNewPicture( decoder_t *p_dec )
 828 {
 829     decoder_sys_t *p_sys = p_dec->p_sys;
 830
 831     picture_dpb_t *p;
 832     int i;
 833
 834     for( i = 0; i < DPB_COUNT; i++ )
 835     {
 836         p = &p_sys->p_dpb[i];
 837         if( !p->p_picture )
 838             break;
 839     }
 840     if( i >= DPB_COUNT )
 841     {
 842         msg_Err( p_dec, "Leaking picture" );
 843         return NULL;
 844     }
 845
 846     p->p_picture = GetNewPicture( p_dec );
 847     if( p->p_picture )
 848     {
 849         decoder_LinkPicture( p_dec, p->p_picture );
 850         p->b_linked = true;
 851         p->b_displayed = false;
 852
 853         p->p_picture->date = 0;
 854     }
 855     return p->p_picture;
 856 }
 857 static picture_dpb_t *DpbFindPicture( decoder_t *p_dec, picture_t *p_picture )
 858 {
 859     decoder_sys_t *p_sys = p_dec->p_sys;
 860
 861     for( int i = 0; i < DPB_COUNT; i++ )
 862     {
 863         picture_dpb_t *p = &p_sys->p_dpb[i];
 864         if( p->p_picture == p_picture )
 865             return p;
 866     }
 867     return NULL;
 868 }
 869 /**
 870  * Unlink the provided picture and ensure that the decoder
 871  * does not own it anymore.
 872  */
 873 static void DpbUnlinkPicture( decoder_t *p_dec, picture_t *p_picture )
 874 {
 875     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 876
 877     /* XXX it is needed to workaround libmpeg2 bugs */
 878     if( !p || !p->b_linked )
 879     {
 880         msg_Err( p_dec, "DpbUnlinkPicture called on an invalid picture" );
 881         return;
 882     }
 883
 884     assert( p && p->b_linked );
 885
 886     decoder_UnlinkPicture( p_dec, p->p_picture );
 887     p->b_linked = false;
 888
 889     if( !p->b_displayed )
 890         decoder_DeletePicture( p_dec, p->p_picture );
 891     p->p_picture = NULL;
 892 }
 893 /**
 894  * Mark the provided picture as displayed.
 895  */
 896 static int DpbDisplayPicture( decoder_t *p_dec, picture_t *p_picture )
 897 {
 898     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 899
 900     /* XXX it is needed to workaround libmpeg2 bugs */
 901     if( !p || p->b_displayed || !p->b_linked )
 902     {
 903         msg_Err( p_dec, "DpbDisplayPicture called on an invalid picture" );
 904         return VLC_EGENERIC;
 905     }
 906
 907     assert( p && !p->b_displayed && p->b_linked );
 908
 909     p->b_displayed = true;
 910     return VLC_SUCCESS;
 911 }
 912
 913