git.sesse.net Git - vlc/blob - modules/codec/libmpeg2.c

   1 /*****************************************************************************
   2  * libmpeg2.c: mpeg2 video decoder module making use of libmpeg2.
   3  *****************************************************************************
   4  * Copyright (C) 1999-2001 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Gildas Bazin <gbazin@videolan.org>
   8  *          Christophe Massiot <massiot@via.ecp.fr>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31 #include <assert.h>
  32
  33 #include <vlc_common.h>
  34 #include <vlc_plugin.h>
  35 #include <vlc_codec.h>
  36 #include <vlc_block_helper.h>
  37 #include <vlc_cpu.h>
  38 #include "../codec/cc.h"
  39
  40 #include <mpeg2.h>
  41
  42 #include <vlc_codec_synchro.h>
  43
  44 /*****************************************************************************
  45  * decoder_sys_t : libmpeg2 decoder descriptor
  46  *****************************************************************************/
  47 #define DPB_COUNT (3+1)
  48 typedef struct
  49 {
  50     picture_t *p_picture;
  51     bool      b_linked;
  52     bool      b_displayed;
  53 } picture_dpb_t;
  54
  55 struct decoder_sys_t
  56 {
  57     /*
  58      * libmpeg2 properties
  59      */
  60     mpeg2dec_t          *p_mpeg2dec;
  61     const mpeg2_info_t  *p_info;
  62     bool                b_skip;
  63
  64     /*
  65      * Input properties
  66      */
  67     mtime_t          i_previous_pts;
  68     mtime_t          i_current_pts;
  69     mtime_t          i_previous_dts;
  70     mtime_t          i_current_dts;
  71     bool             b_garbage_pic;
  72     bool             b_after_sequence_header; /* is it the next frame after
  73                                                * the sequence header ?    */
  74     bool             b_slice_i;             /* intra-slice refresh stream */
  75     bool             b_second_field;
  76
  77     bool             b_preroll;
  78
  79     /* */
  80     picture_dpb_t        p_dpb[DPB_COUNT];
  81
  82     /*
  83      * Output properties
  84      */
  85     decoder_synchro_t *p_synchro;
  86     int             i_sar_num;
  87     int             i_sar_den;
  88     mtime_t         i_last_frame_pts;
  89
  90     /* Closed captioning support */
  91     uint32_t        i_cc_flags;
  92     mtime_t         i_cc_pts;
  93     mtime_t         i_cc_dts;
  94     cc_data_t       cc;
  95     uint8_t        *p_gop_user_data;
  96     uint32_t        i_gop_user_data;
  97 };
  98
  99 /*****************************************************************************
 100  * Local prototypes
 101  *****************************************************************************/
 102 static int  OpenDecoder( vlc_object_t * );
 103 static void CloseDecoder( vlc_object_t * );
 104
 105 static picture_t *DecodeBlock( decoder_t *, block_t ** );
 106 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 107 static block_t   *GetCc( decoder_t *p_dec, bool pb_present[4] );
 108 #endif
 109
 110 static picture_t *GetNewPicture( decoder_t * );
 111 static void PutPicture( decoder_t *, picture_t * );
 112
 113 static void GetAR( decoder_t *p_dec );
 114
 115 static void Reset( decoder_t *p_dec );
 116
 117 /* */
 118 static void DpbInit( decoder_t * );
 119 static void DpbClean( decoder_t * );
 120 static picture_t *DpbNewPicture( decoder_t * );
 121 static void DpbUnlinkPicture( decoder_t *, picture_t * );
 122 static int DpbDisplayPicture( decoder_t *, picture_t * );
 123
 124 /*****************************************************************************
 125  * Module descriptor
 126  *****************************************************************************/
 127 vlc_module_begin ()
 128     set_description( N_("MPEG I/II video decoder (using libmpeg2)") )
 129     set_capability( "decoder", 50 )
 130     set_category( CAT_INPUT )
 131     set_subcategory( SUBCAT_INPUT_VCODEC )
 132     set_callbacks( OpenDecoder, CloseDecoder )
 133     add_shortcut( "libmpeg2" )
 134 vlc_module_end ()
 135
 136 /*****************************************************************************
 137  * OpenDecoder: probe the decoder and return score
 138  *****************************************************************************/
 139 static int OpenDecoder( vlc_object_t *p_this )
 140 {
 141     decoder_t *p_dec = (decoder_t*)p_this;
 142     decoder_sys_t *p_sys;
 143     uint32_t i_accel = 0;
 144
 145     if( p_dec->fmt_in.i_codec != VLC_CODEC_MPGV )
 146         return VLC_EGENERIC;
 147
 148     /* Select onl recognized original format (standard mpeg video) */
 149     switch( p_dec->fmt_in.i_original_fourcc )
 150     {
 151     case VLC_FOURCC('m','p','g','1'):
 152     case VLC_FOURCC('m','p','g','2'):
 153     case VLC_FOURCC('m','p','g','v'):
 154     case VLC_FOURCC('P','I','M','1'):
 155     case VLC_FOURCC('h','d','v','2'):
 156         break;
 157     default:
 158         if( p_dec->fmt_in.i_original_fourcc )
 159             return VLC_EGENERIC;
 160         break;
 161     }
 162
 163     /* Allocate the memory needed to store the decoder's structure */
 164     if( ( p_dec->p_sys = p_sys = calloc( 1, sizeof(*p_sys)) ) == NULL )
 165         return VLC_ENOMEM;
 166
 167     /* Initialize the thread properties */
 168     p_sys->p_mpeg2dec = NULL;
 169     p_sys->p_synchro  = NULL;
 170     p_sys->p_info     = NULL;
 171     p_sys->i_current_pts  = 0;
 172     p_sys->i_previous_pts = 0;
 173     p_sys->i_current_dts  = 0;
 174     p_sys->i_previous_dts = 0;
 175     p_sys->i_sar_num = 0;
 176     p_sys->i_sar_den = 0;
 177     p_sys->b_garbage_pic = false;
 178     p_sys->b_slice_i  = false;
 179     p_sys->b_second_field = false;
 180     p_sys->b_skip     = false;
 181     p_sys->b_preroll = false;
 182     DpbInit( p_dec );
 183
 184     p_sys->i_cc_pts = 0;
 185     p_sys->i_cc_dts = 0;
 186     p_sys->i_cc_flags = 0;
 187 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 188     p_dec->pf_get_cc = GetCc;
 189     cc_Init( &p_sys->cc );
 190 #endif
 191     p_sys->p_gop_user_data = NULL;
 192     p_sys->i_gop_user_data = 0;
 193
 194 #if defined( __i386__ ) || defined( __x86_64__ )
 195     unsigned cpu = vlc_CPU();
 196     if( vlc_CPU_MMX() )
 197         i_accel |= MPEG2_ACCEL_X86_MMX;
 198     if( cpu & CPU_CAPABILITY_3DNOW )
 199         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 200     if( vlc_CPU_MMXEXT() )
 201         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 202 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 203     if( vlc_CPU_ALTIVEC() )
 204         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 205
 206 #elif defined(__arm__)
 207 # ifdef MPEG2_ACCEL_ARM
 208     i_accel |= MPEG2_ACCEL_ARM;
 209 # endif
 210 # ifdef MPEG2_ACCEL_ARM_NEON
 211     if( vlc_CPU_ARM_NEON() )
 212         i_accel |= MPEG2_ACCEL_ARM_NEON;
 213 # endif
 214
 215     /* TODO: sparc */
 216 #else
 217     /* If we do not know this CPU, trust libmpeg2's feature detection */
 218     i_accel = MPEG2_ACCEL_DETECT;
 219
 220 #endif
 221
 222     /* Set CPU acceleration features */
 223     mpeg2_accel( i_accel );
 224
 225     /* Initialize decoder */
 226     p_sys->p_mpeg2dec = mpeg2_init();
 227     if( p_sys->p_mpeg2dec == NULL)
 228     {
 229         msg_Err( p_dec, "mpeg2_init() failed" );
 230         free( p_sys );
 231         return VLC_EGENERIC;
 232     }
 233
 234     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 235
 236     p_dec->pf_decode_video = DecodeBlock;
 237     p_dec->fmt_out.i_cat = VIDEO_ES;
 238     p_dec->fmt_out.i_codec = 0;
 239
 240     return VLC_SUCCESS;
 241 }
 242
 243 /*****************************************************************************
 244  * RunDecoder: the libmpeg2 decoder
 245  *****************************************************************************/
 246 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 247 {
 248     decoder_sys_t   *p_sys = p_dec->p_sys;
 249     mpeg2_state_t   state;
 250     picture_t       *p_pic;
 251
 252     block_t *p_block;
 253
 254     if( !pp_block || !*pp_block )
 255         return NULL;
 256
 257     p_block = *pp_block;
 258     if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY | BLOCK_FLAG_CORRUPTED) )
 259         Reset( p_dec );
 260
 261     while( 1 )
 262     {
 263         state = mpeg2_parse( p_sys->p_mpeg2dec );
 264
 265         switch( state )
 266         {
 267         case STATE_SEQUENCE:
 268         {
 269             /* */
 270             DpbClean( p_dec );
 271
 272             /* */
 273             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 274
 275             /* Set the first 2 reference frames */
 276             p_sys->i_sar_num = 0;
 277             p_sys->i_sar_den = 0;
 278             GetAR( p_dec );
 279             for( int i = 0; i < 2; i++ )
 280             {
 281                 picture_t *p_picture = DpbNewPicture( p_dec );
 282                 if( !p_picture )
 283                 {
 284                     Reset( p_dec );
 285                     block_Release( p_block );
 286                     return NULL;
 287                 }
 288                 PutPicture( p_dec, p_picture );
 289             }
 290
 291             if( p_sys->p_synchro )
 292                 decoder_SynchroRelease( p_sys->p_synchro );
 293
 294             if( p_sys->p_info->sequence->frame_period <= 0 )
 295                 p_sys->p_synchro = NULL;
 296             else
 297                 p_sys->p_synchro =
 298                 decoder_SynchroInit( p_dec, (uint32_t)(UINT64_C(1001000000) *
 299                                 27 / p_sys->p_info->sequence->frame_period) );
 300             p_sys->b_after_sequence_header = true;
 301             break;
 302         }
 303
 304         case STATE_GOP:
 305             /* There can be userdata in a GOP. It needs to be remembered for the next picture. */
 306             if( p_sys->p_info->user_data_len > 2 )
 307             {
 308                 free( p_sys->p_gop_user_data );
 309                 p_sys->p_gop_user_data = calloc( p_sys->p_info->user_data_len, sizeof(uint8_t) );
 310                 if( p_sys->p_gop_user_data )
 311                 {
 312                     p_sys->i_gop_user_data = p_sys->p_info->user_data_len;
 313                     memcpy( p_sys->p_gop_user_data, p_sys->p_info->user_data, p_sys->p_info->user_data_len );
 314                 }
 315             }
 316             break;
 317
 318         case STATE_PICTURE:
 319         {
 320             const mpeg2_info_t *p_info = p_sys->p_info;
 321             const mpeg2_picture_t *p_current = p_info->current_picture;
 322
 323             mtime_t i_pts, i_dts;
 324
 325             if( p_sys->b_after_sequence_header &&
 326                 (p_current->flags &
 327                     PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 328             {
 329                 /* Intra-slice refresh. Simulate a blank I picture. */
 330                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 331                 decoder_SynchroNewPicture( p_sys->p_synchro,
 332                                            I_CODING_TYPE, 2, 0, 0,
 333                                            p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 334                 decoder_SynchroDecode( p_sys->p_synchro );
 335                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 336                 p_sys->b_slice_i = true;
 337             }
 338             p_sys->b_after_sequence_header = false;
 339
 340 #ifdef PIC_FLAG_PTS
 341             i_pts = p_current->flags & PIC_FLAG_PTS ?
 342                 ( ( p_current->pts ==
 343                     (uint32_t)p_sys->i_current_pts ) ?
 344                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 345             i_dts = 0;
 346
 347             /* Hack to handle demuxers which only have DTS timestamps */
 348             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 349             {
 350                 if( p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 351                     (p_current->flags &
 352                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 353                 {
 354                     i_pts = p_block->i_dts;
 355                 }
 356             }
 357             p_block->i_pts = p_block->i_dts = 0;
 358             /* End hack */
 359
 360 #else /* New interface */
 361
 362             i_pts = p_current->flags & PIC_FLAG_TAGS ?
 363                 ( ( p_current->tag == (uint32_t)p_sys->i_current_pts ) ?
 364                             p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 365             i_dts = p_current->flags & PIC_FLAG_TAGS ?
 366                 ( ( p_current->tag2 == (uint32_t)p_sys->i_current_dts ) ?
 367                             p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 368 #endif
 369
 370             /* If nb_fields == 1, it is a field picture, and it will be
 371              * followed by another field picture for which we won't call
 372              * decoder_SynchroNewPicture() because this would have other
 373              * problems, so we take it into account here.
 374              * This kind of sucks, but I didn't think better. --Meuuh
 375              */
 376             decoder_SynchroNewPicture( p_sys->p_synchro,
 377                                        p_current->flags & PIC_MASK_CODING_TYPE,
 378                                        p_current->nb_fields == 1 ? 2 :
 379                                        p_current->nb_fields, i_pts, i_dts,
 380                                        p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 381
 382
 383             bool b_skip = false;
 384             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 385                 !(p_sys->b_slice_i
 386                    && ((p_current->flags
 387                          & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P))
 388                    && !decoder_SynchroChoose( p_sys->p_synchro,
 389                               p_current->flags
 390                                 & PIC_MASK_CODING_TYPE,
 391                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 392                               p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 393             {
 394                 b_skip = true;
 395             }
 396
 397             p_pic = NULL;
 398             if( !b_skip )
 399             {
 400                 p_pic = DpbNewPicture( p_dec );
 401                 if( !p_pic )
 402                 {
 403                     Reset( p_dec );
 404
 405                     p_pic = DpbNewPicture( p_dec );
 406                     if( !p_pic )
 407                     {
 408                         mpeg2_reset( p_sys->p_mpeg2dec, 1 );
 409                         block_Release( p_block );
 410                         return NULL;
 411                     }
 412                 }
 413             }
 414
 415             if( b_skip || !p_pic )
 416             {
 417                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 418                 p_sys->b_skip = true;
 419                 decoder_SynchroTrash( p_sys->p_synchro );
 420
 421                 PutPicture( p_dec, NULL );
 422
 423                 if( !b_skip )
 424                 {
 425                     block_Release( p_block );
 426                     return NULL;
 427                 }
 428             }
 429             else
 430             {
 431                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 432                 p_sys->b_skip = false;
 433                 decoder_SynchroDecode( p_sys->p_synchro );
 434
 435                 PutPicture( p_dec, p_pic );
 436             }
 437             if( p_info->user_data_len > 2 || p_sys->i_gop_user_data > 2 )
 438             {
 439                 p_sys->i_cc_pts = i_pts;
 440                 p_sys->i_cc_dts = i_dts;
 441                 if( (p_current->flags
 442                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 443                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
 444                 else if( (p_current->flags
 445                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 446                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
 447                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
 448                 bool b_top_field_first = p_sys->p_info->current_picture->flags
 449                                            & PIC_FLAG_TOP_FIELD_FIRST;
 450
 451                 if( p_sys->i_gop_user_data > 2 )
 452                 {
 453                     /* We now have picture info for any cached user_data out of the gop */
 454                     cc_Extract( &p_sys->cc, b_top_field_first,
 455                                 &p_sys->p_gop_user_data[0], p_sys->i_gop_user_data );
 456                     p_sys->i_gop_user_data = 0;
 457                 }
 458
 459                 /* Extract the CC from the user_data of the picture */
 460                 if( p_info->user_data_len > 2 )
 461                     cc_Extract( &p_sys->cc, b_top_field_first,
 462                                 &p_info->user_data[0], p_info->user_data_len );
 463             }
 464         }
 465         break;
 466
 467
 468         case STATE_BUFFER:
 469             if( !p_block->i_buffer )
 470             {
 471                 block_Release( p_block );
 472                 return NULL;
 473             }
 474
 475             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 476                                       | BLOCK_FLAG_CORRUPTED)) &&
 477                 p_sys->p_synchro &&
 478                 p_sys->p_info->sequence &&
 479                 p_sys->p_info->sequence->width != (unsigned)-1 )
 480             {
 481                 decoder_SynchroReset( p_sys->p_synchro );
 482                 if( p_sys->p_info->current_fbuf != NULL &&
 483                     p_sys->p_info->current_fbuf->id != NULL )
 484                 {
 485                     p_sys->b_garbage_pic = true;
 486                 }
 487                 if( p_sys->b_slice_i )
 488                 {
 489                     decoder_SynchroNewPicture( p_sys->p_synchro,
 490                                                I_CODING_TYPE, 2, 0, 0,
 491                                                p_sys->p_info->sequence->flags &
 492                                                             SEQ_FLAG_LOW_DELAY );
 493                     decoder_SynchroDecode( p_sys->p_synchro );
 494                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 495                 }
 496             }
 497
 498             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 499             {
 500                 p_sys->b_preroll = true;
 501             }
 502             else if( p_sys->b_preroll )
 503             {
 504                 p_sys->b_preroll = false;
 505                 if( p_sys->p_synchro )
 506                     decoder_SynchroReset( p_sys->p_synchro );
 507             }
 508
 509 #ifdef PIC_FLAG_PTS
 510             if( p_block->i_pts )
 511             {
 512                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 513
 514 #else /* New interface */
 515             if( p_block->i_pts || p_block->i_dts )
 516             {
 517                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 518                                    (uint32_t)p_block->i_pts,
 519                                    (uint32_t)p_block->i_dts );
 520 #endif
 521                 p_sys->i_previous_pts = p_sys->i_current_pts;
 522                 p_sys->i_current_pts = p_block->i_pts;
 523                 p_sys->i_previous_dts = p_sys->i_current_dts;
 524                 p_sys->i_current_dts = p_block->i_dts;
 525             }
 526
 527             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 528                           p_block->p_buffer + p_block->i_buffer );
 529
 530             p_block->i_buffer = 0;
 531             break;
 532
 533 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 534
 535         case STATE_SEQUENCE_MODIFIED:
 536             GetAR( p_dec );
 537             break;
 538 #endif
 539         case STATE_PICTURE_2ND:
 540             p_sys->b_second_field = true;
 541             break;
 542
 543
 544         case STATE_INVALID_END:
 545         case STATE_END:
 546         case STATE_SLICE:
 547             p_pic = NULL;
 548             if( p_sys->p_info->display_fbuf &&
 549                 p_sys->p_info->display_fbuf->id )
 550             {
 551                 p_pic = p_sys->p_info->display_fbuf->id;
 552                 if( DpbDisplayPicture( p_dec, p_pic ) )
 553                     p_pic = NULL;
 554
 555                 decoder_SynchroEnd( p_sys->p_synchro,
 556                                     p_sys->p_info->display_picture->flags & PIC_MASK_CODING_TYPE,
 557                                     p_sys->b_garbage_pic );
 558
 559                 if( p_pic )
 560                 {
 561                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
 562                     if( p_sys->b_garbage_pic )
 563                         p_pic->date = 0; /* ??? */
 564                     p_sys->b_garbage_pic = false;
 565                 }
 566             }
 567
 568             if( p_sys->p_info->discard_fbuf &&
 569                 p_sys->p_info->discard_fbuf->id )
 570             {
 571                 DpbUnlinkPicture( p_dec, p_sys->p_info->discard_fbuf->id );
 572             }
 573
 574             /* For still frames */
 575             if( state == STATE_END && p_pic )
 576                 p_pic->b_force = true;
 577
 578             if( p_pic )
 579             {
 580                 /* Avoid frames with identical timestamps.
 581                  * Especially needed for still frames in DVD menus. */
 582                 if( p_sys->i_last_frame_pts == p_pic->date )
 583                     p_pic->date++;
 584                 p_sys->i_last_frame_pts = p_pic->date;
 585                 return p_pic;
 586             }
 587             break;
 588
 589         case STATE_INVALID:
 590         {
 591             msg_Err( p_dec, "invalid picture encountered" );
 592             /* I don't think we have anything to do, but well without
 593              * docs ... */
 594             break;
 595         }
 596
 597         default:
 598             break;
 599         }
 600     }
 601
 602     /* Never reached */
 603     return NULL;
 604 }
 605
 606 /*****************************************************************************
 607  * CloseDecoder: libmpeg2 decoder destruction
 608  *****************************************************************************/
 609 static void CloseDecoder( vlc_object_t *p_this )
 610 {
 611     decoder_t *p_dec = (decoder_t *)p_this;
 612     decoder_sys_t *p_sys = p_dec->p_sys;
 613
 614     DpbClean( p_dec );
 615
 616     free( p_sys->p_gop_user_data );
 617
 618     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
 619
 620     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 621
 622     free( p_sys );
 623 }
 624
 625 /*****************************************************************************
 626  * Reset: reset the decoder state
 627  *****************************************************************************/
 628 static void Reset( decoder_t *p_dec )
 629 {
 630     decoder_sys_t *p_sys = p_dec->p_sys;
 631
 632     cc_Flush( &p_sys->cc );
 633     mpeg2_reset( p_sys->p_mpeg2dec, 0 );
 634     DpbClean( p_dec );
 635 }
 636
 637 /*****************************************************************************
 638  * GetNewPicture: Get a new picture from the vout and set the buf struct
 639  *****************************************************************************/
 640 static picture_t *GetNewPicture( decoder_t *p_dec )
 641 {
 642     decoder_sys_t *p_sys = p_dec->p_sys;
 643     picture_t *p_pic;
 644
 645     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 646     p_dec->fmt_out.video.i_visible_width =
 647         p_sys->p_info->sequence->picture_width;
 648     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 649     p_dec->fmt_out.video.i_visible_height =
 650         p_sys->p_info->sequence->picture_height;
 651     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 652     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 653
 654     if( p_sys->p_info->sequence->frame_period > 0 )
 655     {
 656         p_dec->fmt_out.video.i_frame_rate =
 657             (uint32_t)( (uint64_t)1001000000 * 27 /
 658                         p_sys->p_info->sequence->frame_period );
 659         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 660     }
 661
 662     p_dec->fmt_out.i_codec =
 663         ( p_sys->p_info->sequence->chroma_height <
 664           p_sys->p_info->sequence->height ) ?
 665         VLC_CODEC_I420 : VLC_CODEC_I422;
 666
 667     /* Get a new picture */
 668     p_pic = decoder_NewPicture( p_dec );
 669
 670     if( p_pic == NULL )
 671         return NULL;
 672
 673     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 674         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 675     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 676         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 677     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 678         p_sys->p_info->current_picture->nb_fields : 2;
 679
 680     return p_pic;
 681 }
 682
 683 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 684 /*****************************************************************************
 685  * GetCc: Retrieves the Closed Captions for the CC decoder.
 686  *****************************************************************************/
 687 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
 688 {
 689     decoder_sys_t   *p_sys = p_dec->p_sys;
 690     block_t         *p_cc = NULL;
 691     int i;
 692
 693     for( i = 0; i < 4; i++ )
 694         pb_present[i] = p_sys->cc.pb_present[i];
 695
 696     if( p_sys->cc.i_data <= 0 )
 697         return NULL;
 698
 699     p_cc = block_New( p_dec, p_sys->cc.i_data);
 700     if( p_cc )
 701     {
 702         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
 703         p_cc->i_dts =
 704         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
 705         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);
 706     }
 707     cc_Flush( &p_sys->cc );
 708     return p_cc;
 709 }
 710 #endif
 711
 712 /*****************************************************************************
 713  * GetAR: Get aspect ratio
 714  *****************************************************************************/
 715 static void GetAR( decoder_t *p_dec )
 716 {
 717     decoder_sys_t *p_sys = p_dec->p_sys;
 718     int i_old_sar_num = p_sys->i_sar_num;
 719     int i_old_sar_den = p_sys->i_sar_den;
 720
 721     /* Check whether the input gave a particular aspect ratio */
 722     if( p_dec->fmt_in.video.i_sar_num > 0 &&
 723         p_dec->fmt_in.video.i_sar_den > 0 )
 724     {
 725         p_sys->i_sar_num = p_dec->fmt_in.video.i_sar_num;
 726         p_sys->i_sar_den = p_dec->fmt_in.video.i_sar_den;
 727     }
 728     else
 729     {
 730         /* Use the value provided in the MPEG sequence header */
 731         if( p_sys->p_info->sequence->pixel_height > 0 )
 732         {
 733             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 734             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 735         }
 736         else
 737         {
 738             /* Invalid aspect, assume 4:3.
 739              * This shouldn't happen and if it does it is a bug
 740              * in libmpeg2 (likely triggered by an invalid stream) */
 741             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 742             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 743         }
 744     }
 745
 746     if( p_sys->i_sar_num == i_old_sar_num &&
 747         p_sys->i_sar_den == i_old_sar_den )
 748         return;
 749
 750     if( p_sys->p_info->sequence->frame_period > 0 )
 751         msg_Dbg( p_dec,
 752                  "%dx%d (display %d,%d), sar %i:%i, %u.%03u fps",
 753                  p_sys->p_info->sequence->picture_width,
 754                  p_sys->p_info->sequence->picture_height,
 755                  p_sys->p_info->sequence->display_width,
 756                  p_sys->p_info->sequence->display_height,
 757                  p_sys->i_sar_num, p_sys->i_sar_den,
 758                  (uint32_t)((uint64_t)1001000000 * 27 /
 759                      p_sys->p_info->sequence->frame_period / 1001),
 760                  (uint32_t)((uint64_t)1001000000 * 27 /
 761                      p_sys->p_info->sequence->frame_period % 1001) );
 762     else
 763         msg_Dbg( p_dec, "bad frame period" );
 764 }
 765
 766 /*****************************************************************************
 767  * PutPicture: Put a picture_t in mpeg2 context
 768  *****************************************************************************/
 769 static void PutPicture( decoder_t *p_dec, picture_t *p_picture )
 770 {
 771     decoder_sys_t *p_sys = p_dec->p_sys;
 772
 773     /* */
 774     uint8_t *pp_buf[3];
 775     for( int j = 0; j < 3; j++ )
 776         pp_buf[j] = p_picture ? p_picture->p[j].p_pixels : NULL;
 777     mpeg2_set_buf( p_sys->p_mpeg2dec, pp_buf, p_picture );
 778
 779     /* Completly broken API, why the hell does it suppose
 780      * the stride of the chroma planes ! */
 781     if( p_picture )
 782         mpeg2_stride( p_sys->p_mpeg2dec, p_picture->p[Y_PLANE].i_pitch );
 783 }
 784
 785
 786 /**
 787  * Initialize a virtual Decoded Picture Buffer to workaround
 788  * libmpeg2 deficient API
 789  */
 790 static void DpbInit( decoder_t *p_dec )
 791 {
 792     decoder_sys_t *p_sys = p_dec->p_sys;
 793
 794     for( int i = 0; i < DPB_COUNT; i++ )
 795         p_sys->p_dpb[i].p_picture = NULL;
 796 }
 797 /**
 798  * Empty and reset the current DPB
 799  */
 800 static void DpbClean( decoder_t *p_dec )
 801 {
 802     decoder_sys_t *p_sys = p_dec->p_sys;
 803
 804     for( int i = 0; i < DPB_COUNT; i++ )
 805     {
 806         picture_dpb_t *p = &p_sys->p_dpb[i];
 807         if( !p->p_picture )
 808             continue;
 809         if( p->b_linked )
 810             decoder_UnlinkPicture( p_dec, p->p_picture );
 811         if( !p->b_displayed )
 812             decoder_DeletePicture( p_dec, p->p_picture );
 813
 814         p->p_picture = NULL;
 815     }
 816 }
 817 /**
 818  * Retreive a picture and reserve a place in the DPB
 819  */
 820 static picture_t *DpbNewPicture( decoder_t *p_dec )
 821 {
 822     decoder_sys_t *p_sys = p_dec->p_sys;
 823
 824     picture_dpb_t *p;
 825     int i;
 826
 827     for( i = 0; i < DPB_COUNT; i++ )
 828     {
 829         p = &p_sys->p_dpb[i];
 830         if( !p->p_picture )
 831             break;
 832     }
 833     if( i >= DPB_COUNT )
 834     {
 835         msg_Err( p_dec, "Leaking picture" );
 836         return NULL;
 837     }
 838
 839     p->p_picture = GetNewPicture( p_dec );
 840     if( p->p_picture )
 841     {
 842         decoder_LinkPicture( p_dec, p->p_picture );
 843         p->b_linked = true;
 844         p->b_displayed = false;
 845
 846         p->p_picture->date = 0;
 847     }
 848     return p->p_picture;
 849 }
 850 static picture_dpb_t *DpbFindPicture( decoder_t *p_dec, picture_t *p_picture )
 851 {
 852     decoder_sys_t *p_sys = p_dec->p_sys;
 853
 854     for( int i = 0; i < DPB_COUNT; i++ )
 855     {
 856         picture_dpb_t *p = &p_sys->p_dpb[i];
 857         if( p->p_picture == p_picture )
 858             return p;
 859     }
 860     return NULL;
 861 }
 862 /**
 863  * Unlink the provided picture and ensure that the decoder
 864  * does not own it anymore.
 865  */
 866 static void DpbUnlinkPicture( decoder_t *p_dec, picture_t *p_picture )
 867 {
 868     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 869
 870     /* XXX it is needed to workaround libmpeg2 bugs */
 871     if( !p || !p->b_linked )
 872     {
 873         msg_Err( p_dec, "DpbUnlinkPicture called on an invalid picture" );
 874         return;
 875     }
 876
 877     assert( p && p->b_linked );
 878
 879     decoder_UnlinkPicture( p_dec, p->p_picture );
 880     p->b_linked = false;
 881
 882     if( !p->b_displayed )
 883         decoder_DeletePicture( p_dec, p->p_picture );
 884     p->p_picture = NULL;
 885 }
 886 /**
 887  * Mark the provided picture as displayed.
 888  */
 889 static int DpbDisplayPicture( decoder_t *p_dec, picture_t *p_picture )
 890 {
 891     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
 892
 893     /* XXX it is needed to workaround libmpeg2 bugs */
 894     if( !p || p->b_displayed || !p->b_linked )
 895     {
 896         msg_Err( p_dec, "DpbDisplayPicture called on an invalid picture" );
 897         return VLC_EGENERIC;
 898     }
 899
 900     assert( p && !p->b_displayed && p->b_linked );
 901
 902     p->b_displayed = true;
 903     return VLC_SUCCESS;
 904 }
 905
 906