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