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