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
 258     block_t *p_block;
 259
 260     if( !pp_block || !*pp_block )
 261         return NULL;
 262
 263     p_block = *pp_block;
 264     if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY | BLOCK_FLAG_CORRUPTED) )
 265         Reset( p_dec );
 266
 267     while( 1 )
 268     {
 269         state = mpeg2_parse( p_sys->p_mpeg2dec );
 270
 271         switch( state )
 272         {
 273         case STATE_SEQUENCE:
 274         {
 275             /* */
 276             DpbClean( p_dec );
 277
 278             /* */
 279             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 280
 281             /* Set the first 2 reference frames */
 282             p_sys->i_sar_num = 0;
 283             p_sys->i_sar_den = 0;
 284             GetAR( p_dec );
 285             for( int i = 0; i < 2; i++ )
 286             {
 287                 picture_t *p_picture = DpbNewPicture( p_dec );
 288                 if( !p_picture )
 289                 {
 290                     Reset( p_dec );
 291                     block_Release( p_block );
 292                     return NULL;
 293                 }
 294                 PutPicture( p_dec, p_picture );
 295             }
 296
 297             if( p_sys->p_synchro )
 298                 decoder_SynchroRelease( p_sys->p_synchro );
 299
 300             if( p_sys->p_info->sequence->frame_period <= 0 )
 301                 p_sys->p_synchro = NULL;
 302             else
 303                 p_sys->p_synchro =
 304                 decoder_SynchroInit( p_dec, (uint32_t)(UINT64_C(1001000000) *
 305                                 27 / p_sys->p_info->sequence->frame_period) );
 306             p_sys->b_after_sequence_header = true;
 307             break;
 308         }
 309
 310         case STATE_GOP:
 311             /* There can be userdata in a GOP. It needs to be remembered for the next picture. */
 312             if( p_sys->p_info->user_data_len > 2 )
 313             {
 314                 free( p_sys->p_gop_user_data );
 315                 p_sys->p_gop_user_data = calloc( p_sys->p_info->user_data_len, sizeof(uint8_t) );
 316                 if( p_sys->p_gop_user_data )
 317                 {
 318                     p_sys->i_gop_user_data = p_sys->p_info->user_data_len;
 319                     memcpy( p_sys->p_gop_user_data, p_sys->p_info->user_data, p_sys->p_info->user_data_len );
 320                 }
 321             }
 322             break;
 323
 324         case STATE_PICTURE:
 325         {
 326             const mpeg2_info_t *p_info = p_sys->p_info;
 327             const mpeg2_picture_t *p_current = p_info->current_picture;
 328
 329             mtime_t i_pts, i_dts;
 330
 331             if( p_sys->b_after_sequence_header &&
 332                 (p_current->flags &
 333                     PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 334             {
 335                 /* Intra-slice refresh. Simulate a blank I picture. */
 336                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 337                 decoder_SynchroNewPicture( p_sys->p_synchro,
 338                                            I_CODING_TYPE, 2, 0, 0,
 339                                            p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 340                 decoder_SynchroDecode( p_sys->p_synchro );
 341                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 342                 p_sys->b_slice_i = true;
 343             }
 344             p_sys->b_after_sequence_header = false;
 345
 346 #ifdef PIC_FLAG_PTS
 347             i_pts = p_current->flags & PIC_FLAG_PTS ?
 348                 ( ( p_current->pts ==
 349                     (uint32_t)p_sys->i_current_pts ) ?
 350                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 351             i_dts = 0;
 352
 353             /* Hack to handle demuxers which only have DTS timestamps */
 354             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 355             {
 356                 if( p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 357                     (p_current->flags &
 358                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 359                 {
 360                     i_pts = p_block->i_dts;
 361                 }
 362             }
 363             p_block->i_pts = p_block->i_dts = 0;
 364             /* End hack */
 365
 366 #else /* New interface */
 367
 368             i_pts = p_current->flags & PIC_FLAG_TAGS ?
 369                 ( ( p_current->tag == (uint32_t)p_sys->i_current_pts ) ?
 370                             p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 371             i_dts = p_current->flags & PIC_FLAG_TAGS ?
 372                 ( ( p_current->tag2 == (uint32_t)p_sys->i_current_dts ) ?
 373                             p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 374 #endif
 375
 376             /* If nb_fields == 1, it is a field picture, and it will be
 377              * followed by another field picture for which we won't call
 378              * decoder_SynchroNewPicture() because this would have other
 379              * problems, so we take it into account here.
 380              * This kind of sucks, but I didn't think better. --Meuuh
 381              */
 382             decoder_SynchroNewPicture( p_sys->p_synchro,
 383                                        p_current->flags & PIC_MASK_CODING_TYPE,
 384                                        p_current->nb_fields == 1 ? 2 :
 385                                        p_current->nb_fields, i_pts, i_dts,
 386                                        p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 387
 388
 389             picture_t *p_pic;
 390
 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                 p_pic = NULL;
 401             else
 402             {
 403                 p_pic = DpbNewPicture( p_dec );
 404                 if( !p_pic )
 405                 {
 406                     Reset( p_dec );
 407
 408                     p_pic = DpbNewPicture( p_dec );
 409                     if( !p_pic )
 410                     {
 411                         mpeg2_reset( p_sys->p_mpeg2dec, 1 );
 412                         block_Release( p_block );
 413                         return NULL;
 414                     }
 415                 }
 416             }
 417
 418             mpeg2_skip( p_sys->p_mpeg2dec, p_pic == NULL );
 419             p_sys->b_skip = p_pic == NULL;
 420             if( p_pic != NULL )
 421                 decoder_SynchroDecode( p_sys->p_synchro );
 422             else
 423                 decoder_SynchroTrash( p_sys->p_synchro );
 424
 425             PutPicture( p_dec, p_pic );
 426
 427             if( p_info->user_data_len > 2 || p_sys->i_gop_user_data > 2 )
 428             {
 429                 p_sys->i_cc_pts = i_pts;
 430                 p_sys->i_cc_dts = i_dts;
 431                 if( (p_current->flags
 432                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 433                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
 434                 else if( (p_current->flags
 435                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 436                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
 437                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
 438                 bool b_top_field_first = p_sys->p_info->current_picture->flags
 439                                            & PIC_FLAG_TOP_FIELD_FIRST;
 440
 441                 if( p_sys->i_gop_user_data > 2 )
 442                 {
 443                     /* We now have picture info for any cached user_data out of the gop */
 444                     cc_Extract( &p_sys->cc, b_top_field_first,
 445                                 &p_sys->p_gop_user_data[0], p_sys->i_gop_user_data );
 446                     p_sys->i_gop_user_data = 0;
 447                 }
 448
 449                 /* Extract the CC from the user_data of the picture */
 450                 if( p_info->user_data_len > 2 )
 451                     cc_Extract( &p_sys->cc, b_top_field_first,
 452                                 &p_info->user_data[0], p_info->user_data_len );
 453             }
 454         }
 455         break;
 456
 457
 458         case STATE_BUFFER:
 459             if( !p_block->i_buffer )
 460             {
 461                 block_Release( p_block );
 462                 return NULL;
 463             }
 464
 465             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 466                                       | BLOCK_FLAG_CORRUPTED)) &&
 467                 p_sys->p_synchro &&
 468                 p_sys->p_info->sequence &&
 469                 p_sys->p_info->sequence->width != (unsigned)-1 )
 470             {
 471                 decoder_SynchroReset( p_sys->p_synchro );
 472                 if( p_sys->p_info->current_fbuf != NULL &&
 473                     p_sys->p_info->current_fbuf->id != NULL )
 474                 {
 475                     p_sys->b_garbage_pic = true;
 476                 }
 477                 if( p_sys->b_slice_i )
 478                 {
 479                     decoder_SynchroNewPicture( p_sys->p_synchro,
 480                                                I_CODING_TYPE, 2, 0, 0,
 481                                                p_sys->p_info->sequence->flags &
 482                                                             SEQ_FLAG_LOW_DELAY );
 483                     decoder_SynchroDecode( p_sys->p_synchro );
 484                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 485                 }
 486             }
 487
 488             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 489             {
 490                 p_sys->b_preroll = true;
 491             }
 492             else if( p_sys->b_preroll )
 493             {
 494                 p_sys->b_preroll = false;
 495                 if( p_sys->p_synchro )
 496                     decoder_SynchroReset( p_sys->p_synchro );
 497             }
 498
 499 #ifdef PIC_FLAG_PTS
 500             if( p_block->i_pts )
 501             {
 502                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 503
 504 #else /* New interface */
 505             if( p_block->i_pts || p_block->i_dts )
 506             {
 507                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 508                                    (uint32_t)p_block->i_pts,
 509                                    (uint32_t)p_block->i_dts );
 510 #endif
 511                 p_sys->i_previous_pts = p_sys->i_current_pts;
 512                 p_sys->i_current_pts = p_block->i_pts;
 513                 p_sys->i_previous_dts = p_sys->i_current_dts;
 514                 p_sys->i_current_dts = p_block->i_dts;
 515             }
 516
 517             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 518                           p_block->p_buffer + p_block->i_buffer );
 519
 520             p_block->i_buffer = 0;
 521             break;
 522
 523 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 524
 525         case STATE_SEQUENCE_MODIFIED:
 526             GetAR( p_dec );
 527             break;
 528 #endif
 529         case STATE_PICTURE_2ND:
 530             p_sys->b_second_field = true;
 531             break;
 532
 533
 534         case STATE_INVALID_END:
 535         case STATE_END:
 536         case STATE_SLICE:
 537         {
 538             picture_t *p_pic = NULL;
 539
 540             if( p_sys->p_info->display_fbuf &&
 541                 p_sys->p_info->display_fbuf->id )
 542             {
 543                 p_pic = p_sys->p_info->display_fbuf->id;
 544                 if( DpbDisplayPicture( p_dec, p_pic ) )
 545                     p_pic = NULL;
 546
 547                 decoder_SynchroEnd( p_sys->p_synchro,
 548                                     p_sys->p_info->display_picture->flags & PIC_MASK_CODING_TYPE,
 549                                     p_sys->b_garbage_pic );
 550
 551                 if( p_pic )
 552                 {
 553                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
 554                     if( p_sys->b_garbage_pic )
 555                         p_pic->date = 0; /* ??? */
 556                     p_sys->b_garbage_pic = false;
 557                 }
 558             }
 559
 560             if( p_sys->p_info->discard_fbuf &&
 561                 p_sys->p_info->discard_fbuf->id )
 562             {
 563                 DpbUnlinkPicture( p_dec, p_sys->p_info->discard_fbuf->id );
 564             }
 565
 566             if( p_pic )
 567             {
 568                 if( state == STATE_END )
 569                     p_pic->b_force = true; /* For still frames */
 570
 571                 /* Avoid frames with identical timestamps.
 572                  * Especially needed for still frames in DVD menus. */
 573                 if( p_sys->i_last_frame_pts == p_pic->date )
 574                     p_pic->date++;
 575                 p_sys->i_last_frame_pts = p_pic->date;
 576                 return p_pic;
 577             }
 578             break;
 579         }
 580
 581         case STATE_INVALID:
 582         {
 583             msg_Err( p_dec, "invalid picture encountered" );
 584             /* I don't think we have anything to do, but well without
 585              * docs ... */
 586             break;
 587         }
 588
 589         default:
 590             break;
 591         }
 592     }
 593
 594     /* Never reached */
 595     return NULL;
 596 }
 597
 598 /*****************************************************************************
 599  * CloseDecoder: libmpeg2 decoder destruction
 600  *****************************************************************************/
 601 static void CloseDecoder( vlc_object_t *p_this )
 602 {
 603     decoder_t *p_dec = (decoder_t *)p_this;
 604     decoder_sys_t *p_sys = p_dec->p_sys;
 605
 606     DpbClean( p_dec );
 607
 608     free( p_sys->p_gop_user_data );
 609
 610     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
 611
 612     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 613
 614     free( p_sys );
 615 }
 616
 617 /*****************************************************************************
 618  * Reset: reset the decoder state
 619  *****************************************************************************/
 620 static void Reset( decoder_t *p_dec )
 621 {
 622     decoder_sys_t *p_sys = p_dec->p_sys;
 623
 624     cc_Flush( &p_sys->cc );
 625     mpeg2_reset( p_sys->p_mpeg2dec, 0 );
 626     DpbClean( p_dec );
 627 }
 628
 629 /*****************************************************************************
 630  * GetNewPicture: Get a new picture from the vout and set the buf struct
 631  *****************************************************************************/
 632 static picture_t *GetNewPicture( decoder_t *p_dec )
 633 {
 634     decoder_sys_t *p_sys = p_dec->p_sys;
 635     picture_t *p_pic;
 636
 637     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 638     p_dec->fmt_out.video.i_visible_width =
 639         p_sys->p_info->sequence->picture_width;
 640     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 641     p_dec->fmt_out.video.i_visible_height =
 642         p_sys->p_info->sequence->picture_height;
 643     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 644     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 645
 646     if( p_sys->p_info->sequence->frame_period > 0 )
 647     {
 648         p_dec->fmt_out.video.i_frame_rate =
 649             (uint32_t)( (uint64_t)1001000000 * 27 /
 650                         p_sys->p_info->sequence->frame_period );
 651         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 652     }
 653
 654     p_dec->fmt_out.i_codec =
 655         ( p_sys->p_info->sequence->chroma_height <
 656           p_sys->p_info->sequence->height ) ?
 657         VLC_CODEC_I420 : VLC_CODEC_I422;
 658
 659     /* Get a new picture */
 660     p_pic = decoder_NewPicture( p_dec );
 661
 662     if( p_pic == NULL )
 663         return NULL;
 664
 665     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 666         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 667     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 668         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 669     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 670         p_sys->p_info->current_picture->nb_fields : 2;
 671
 672     return p_pic;
 673 }
 674
 675 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 676 /*****************************************************************************
 677  * GetCc: Retrieves the Closed Captions for the CC decoder.
 678  *****************************************************************************/
 679 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
 680 {
 681     decoder_sys_t   *p_sys = p_dec->p_sys;
 682     block_t         *p_cc = NULL;
 683     int i;
 684
 685     for( i = 0; i < 4; i++ )
 686         pb_present[i] = p_sys->cc.pb_present[i];
 687
 688     if( p_sys->cc.i_data <= 0 )
 689         return NULL;
 690
 691     p_cc = block_Alloc( p_sys->cc.i_data);
 692     if( p_cc )
 693     {
 694         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
 695         p_cc->i_dts =
 696         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
 697         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);
 698     }
 699     cc_Flush( &p_sys->cc );
 700     return p_cc;
 701 }
 702 #endif
 703
 704 /*****************************************************************************
 705  * GetAR: Get aspect ratio
 706  *****************************************************************************/
 707 static void GetAR( decoder_t *p_dec )
 708 {
 709     decoder_sys_t *p_sys = p_dec->p_sys;
 710     int i_old_sar_num = p_sys->i_sar_num;
 711     int i_old_sar_den = p_sys->i_sar_den;
 712
 713     /* Check whether the input gave a particular aspect ratio */
 714     if( p_dec->fmt_in.video.i_sar_num > 0 &&
 715         p_dec->fmt_in.video.i_sar_den > 0 )
 716     {
 717         p_sys->i_sar_num = p_dec->fmt_in.video.i_sar_num;
 718         p_sys->i_sar_den = p_dec->fmt_in.video.i_sar_den;
 719     }
 720     else
 721     {
 722         /* Use the value provided in the MPEG sequence header */
 723         if( p_sys->p_info->sequence->pixel_height > 0 )
 724         {
 725             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 726             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 727         }
 728         else
 729         {
 730             /* Invalid aspect, assume 4:3.
 731              * This shouldn't happen and if it does it is a bug
 732              * in libmpeg2 (likely triggered by an invalid stream) */
 733             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 734             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 735         }
 736     }
 737
 738     if( p_sys->i_sar_num == i_old_sar_num &&
 739         p_sys->i_sar_den == i_old_sar_den )
 740         return;
 741
 742     if( p_sys->p_info->sequence->frame_period > 0 )
 743         msg_Dbg( p_dec,
 744                  "%dx%d (display %d,%d), sar %i:%i, %u.%03u fps",
 745                  p_sys->p_info->sequence->picture_width,
 746                  p_sys->p_info->sequence->picture_height,
 747                  p_sys->p_info->sequence->display_width,
 748                  p_sys->p_info->sequence->display_height,
 749                  p_sys->i_sar_num, p_sys->i_sar_den,
 750                  (uint32_t)((uint64_t)1001000000 * 27 /
 751                      p_sys->p_info->sequence->frame_period / 1001),
 752                  (uint32_t)((uint64_t)1001000000 * 27 /
 753                      p_sys->p_info->sequence->frame_period % 1001) );
 754     else
 755         msg_Dbg( p_dec, "bad frame period" );
 756 }
 757
 758 /*****************************************************************************
 759  * PutPicture: Put a picture_t in mpeg2 context
 760  *****************************************************************************/
 761 static void PutPicture( decoder_t *p_dec, picture_t *p_picture )
 762 {
 763     decoder_sys_t *p_sys = p_dec->p_sys;
 764
 765     /* */
 766     uint8_t *pp_buf[3];
 767     for( int j = 0; j < 3; j++ )
 768         pp_buf[j] = p_picture ? p_picture->p[j].p_pixels : NULL;
 769     mpeg2_set_buf( p_sys->p_mpeg2dec, pp_buf, p_picture );
 770
 771     /* Completly broken API, why the hell does it suppose
 772      * the stride of the chroma planes ! */
 773     if( p_picture )
 774         mpeg2_stride( p_sys->p_mpeg2dec, p_picture->p[Y_PLANE].i_pitch );
 775 }
 776
 777
 778 /**
 779  * Initialize a virtual Decoded Picture Buffer to workaround
 780  * libmpeg2 deficient API
 781  */
 782 static void DpbInit( decoder_t *p_dec )
 783 {
 784     decoder_sys_t *p_sys = p_dec->p_sys;
 785
 786     for( int i = 0; i < DPB_COUNT; i++ )
 787         p_sys->p_dpb[i].p_picture = NULL;
 788 }
 789 /**
 790  * Empty and reset the current DPB
 791  */
 792 static void DpbClean( decoder_t *p_dec )
 793 {
 794     decoder_sys_t *p_sys = p_dec->p_sys;
 795
 796     for( int i = 0; i < DPB_COUNT; i++ )
 797     {
 798         picture_dpb_t *p = &p_sys->p_dpb[i];
 799         if( !p->p_picture )
 800             continue;
 801         if( p->b_linked )
 802             picture_Release( p->p_picture );
 803         if( !p->b_displayed )
 804             picture_Release( p->p_picture );
 805
 806         p->p_picture = NULL;
 807     }
 808 }
 809 /**
 810  * Retreive a picture and reserve a place in the DPB
 811  */
 812 static picture_t *DpbNewPicture( decoder_t *p_dec )
 813 {
 814     decoder_sys_t *p_sys = p_dec->p_sys;
 815
 816     picture_dpb_t *p;
 817     int i;
 818
 819     for( i = 0; i < DPB_COUNT; i++ )
 820     {
 821         p = &p_sys->p_dpb[i];
 822         if( !p->p_picture )
 823             break;
 824     }
 825     if( i >= DPB_COUNT )
 826     {
 827         msg_Err( p_dec, "Leaking picture" );
 828         return NULL;
 829     }
 830
 831     p->p_picture = GetNewPicture( p_dec );
 832     if( p->p_picture )
 833     {
 834         picture_Hold( p->p_picture );
 835         p->b_linked = true;
 836         p->b_displayed = false;
 837
 838         p->p_picture->date = 0;
 839     }
 840     return p->p_picture;
 841 }
 842 static picture_dpb_t *DpbFindPicture( decoder_t *p_dec, picture_t *p_picture )
 843 {
 844     decoder_sys_t *p_sys = p_dec->p_sys;
 845
 846     for( int i = 0; i < DPB_COUNT; i++ )
 847     {
 848         picture_dpb_t *p = &p_sys->p_dpb[i];
 849         if( p->p_picture == p_picture )
 850             return p;
 851     }
 852     return NULL;
 853 }
 854 /**
 855  * Unlink the provided picture and ensure that the decoder
 856  * does not own it anymore.
 857  */
 858 static void DpbUnlinkPicture( decoder_t *p_dec, picture_t *p_picture )
 859 {
 860     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 861
 862     /* XXX it is needed to workaround libmpeg2 bugs */
 863     if( !p || !p->b_linked )
 864     {
 865         msg_Err( p_dec, "DpbUnlinkPicture called on an invalid picture" );
 866         return;
 867     }
 868
 869     assert( p && p->b_linked );
 870
 871     picture_Release( p->p_picture );
 872     p->b_linked = false;
 873
 874     if( !p->b_displayed )
 875         picture_Release( p->p_picture );
 876     p->p_picture = NULL;
 877 }
 878 /**
 879  * Mark the provided picture as displayed.
 880  */
 881 static int DpbDisplayPicture( decoder_t *p_dec, picture_t *p_picture )
 882 {
 883     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 884
 885     /* XXX it is needed to workaround libmpeg2 bugs */
 886     if( !p || p->b_displayed || !p->b_linked )
 887     {
 888         msg_Err( p_dec, "DpbDisplayPicture called on an invalid picture" );
 889         return VLC_EGENERIC;
 890     }
 891
 892     assert( p && !p->b_displayed && p->b_linked );
 893
 894     p->b_displayed = true;
 895     return VLC_SUCCESS;
 896 }
 897
 898