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
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_vout.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 struct decoder_sys_t
  47 {
  48     /*
  49      * libmpeg2 properties
  50      */
  51     mpeg2dec_t          *p_mpeg2dec;
  52     const mpeg2_info_t  *p_info;
  53     bool                b_skip;
  54
  55     /*
  56      * Input properties
  57      */
  58     mtime_t          i_previous_pts;
  59     mtime_t          i_current_pts;
  60     mtime_t          i_previous_dts;
  61     mtime_t          i_current_dts;
  62     picture_t *      p_picture_to_destroy;
  63     bool             b_garbage_pic;
  64     bool             b_after_sequence_header; /* is it the next frame after
  65                                                * the sequence header ?    */
  66     bool             b_slice_i;             /* intra-slice refresh stream */
  67     bool             b_second_field;
  68
  69     bool             b_preroll;
  70
  71     /*
  72      * Output properties
  73      */
  74     decoder_synchro_t *p_synchro;
  75     int             i_aspect;
  76     int             i_sar_num;
  77     int             i_sar_den;
  78     mtime_t         i_last_frame_pts;
  79
  80     /* Closed captioning support */
  81     uint32_t        i_cc_flags;
  82     mtime_t         i_cc_pts;
  83     mtime_t         i_cc_dts;
  84     cc_data_t       cc;
  85 };
  86
  87 /*****************************************************************************
  88  * Local prototypes
  89  *****************************************************************************/
  90 static int  OpenDecoder( vlc_object_t * );
  91 static void CloseDecoder( vlc_object_t * );
  92
  93 static picture_t *DecodeBlock( decoder_t *, block_t ** );
  94 static block_t   *GetCc( decoder_t *p_dec, bool pb_present[4] );
  95
  96 static picture_t *GetNewPicture( decoder_t *, uint8_t ** );
  97 static void GetAR( decoder_t *p_dec );
  98
  99 /*****************************************************************************
 100  * Module descriptor
 101  *****************************************************************************/
 102 vlc_module_begin();
 103     set_description( N_("MPEG I/II video decoder (using libmpeg2)") );
 104     set_capability( "decoder", 150 );
 105     set_category( CAT_INPUT );
 106     set_subcategory( SUBCAT_INPUT_VCODEC );
 107     set_callbacks( OpenDecoder, CloseDecoder );
 108     add_shortcut( "libmpeg2" );
 109 vlc_module_end();
 110
 111 /*****************************************************************************
 112  * OpenDecoder: probe the decoder and return score
 113  *****************************************************************************/
 114 static int OpenDecoder( vlc_object_t *p_this )
 115 {
 116     decoder_t *p_dec = (decoder_t*)p_this;
 117     decoder_sys_t *p_sys;
 118     uint32_t i_accel = 0;
 119
 120     if( p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','v') &&
 121         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','1') &&
 122         /* Pinnacle hardware-mpeg1 */
 123         p_dec->fmt_in.i_codec != VLC_FOURCC('P','I','M','1') &&
 124         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','2','v') &&
 125         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','2') &&
 126         p_dec->fmt_in.i_codec != VLC_FOURCC('h','d','v','2') )
 127     {
 128         return VLC_EGENERIC;
 129     }
 130
 131     /* Allocate the memory needed to store the decoder's structure */
 132     if( ( p_dec->p_sys = p_sys =
 133           (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
 134         return VLC_ENOMEM;
 135
 136     /* Initialize the thread properties */
 137     memset( p_sys, 0, sizeof(decoder_sys_t) );
 138     p_sys->p_mpeg2dec = NULL;
 139     p_sys->p_synchro  = NULL;
 140     p_sys->p_info     = NULL;
 141     p_sys->i_current_pts  = 0;
 142     p_sys->i_previous_pts = 0;
 143     p_sys->i_current_dts  = 0;
 144     p_sys->i_previous_dts = 0;
 145     p_sys->p_picture_to_destroy = NULL;
 146     p_sys->b_garbage_pic = 0;
 147     p_sys->b_slice_i  = 0;
 148     p_sys->b_second_field = 0;
 149     p_sys->b_skip     = 0;
 150     p_sys->b_preroll = false;
 151
 152     p_sys->i_cc_pts = 0;
 153     p_sys->i_cc_dts = 0;
 154     p_sys->i_cc_flags = 0;
 155 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 156     p_dec->pf_get_cc = GetCc;
 157     cc_Init( &p_sys->cc );
 158 #endif
 159
 160 #if defined( __i386__ ) || defined( __x86_64__ )
 161     if( vlc_CPU() & CPU_CAPABILITY_MMX )
 162     {
 163         i_accel |= MPEG2_ACCEL_X86_MMX;
 164     }
 165
 166     if( vlc_CPU() & CPU_CAPABILITY_3DNOW )
 167     {
 168         i_accel |= MPEG2_ACCEL_X86_3DNOW;
 169     }
 170
 171     if( vlc_CPU() & CPU_CAPABILITY_MMXEXT )
 172     {
 173         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
 174     }
 175
 176 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
 177     if( vlc_CPU() & CPU_CAPABILITY_ALTIVEC )
 178     {
 179         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
 180     }
 181
 182 #else
 183     /* If we do not know this CPU, trust libmpeg2's feature detection */
 184     i_accel = MPEG2_ACCEL_DETECT;
 185
 186 #endif
 187
 188     /* Set CPU acceleration features */
 189     mpeg2_accel( i_accel );
 190
 191     /* Initialize decoder */
 192     p_sys->p_mpeg2dec = mpeg2_init();
 193     if( p_sys->p_mpeg2dec == NULL)
 194     {
 195         msg_Err( p_dec, "mpeg2_init() failed" );
 196         free( p_sys );
 197         return VLC_EGENERIC;
 198     }
 199
 200     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 201
 202     p_dec->pf_decode_video = DecodeBlock;
 203
 204     return VLC_SUCCESS;
 205 }
 206
 207 /*****************************************************************************
 208  * RunDecoder: the libmpeg2 decoder
 209  *****************************************************************************/
 210 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 211 {
 212     decoder_sys_t   *p_sys = p_dec->p_sys;
 213     mpeg2_state_t   state;
 214     picture_t       *p_pic;
 215
 216     block_t *p_block;
 217
 218     if( !pp_block || !*pp_block ) return NULL;
 219
 220     p_block = *pp_block;
 221
 222     while( 1 )
 223     {
 224         state = mpeg2_parse( p_sys->p_mpeg2dec );
 225
 226         switch( state )
 227         {
 228         case STATE_BUFFER:
 229             if( !p_block->i_buffer )
 230             {
 231                 block_Release( p_block );
 232                 return NULL;
 233             }
 234             if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 235                                       | BLOCK_FLAG_CORRUPTED))
 236                 cc_Flush( &p_sys->cc );
 237
 238             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
 239                                       | BLOCK_FLAG_CORRUPTED)) &&
 240                 p_sys->p_synchro &&
 241                 p_sys->p_info->sequence &&
 242                 p_sys->p_info->sequence->width != (unsigned)-1 )
 243             {
 244                 decoder_SynchroReset( p_sys->p_synchro );
 245                 if( p_sys->p_info->current_fbuf != NULL
 246                     && p_sys->p_info->current_fbuf->id != NULL )
 247                 {
 248                     p_sys->b_garbage_pic = 1;
 249                     p_pic = p_sys->p_info->current_fbuf->id;
 250                 }
 251                 else
 252                 {
 253                     uint8_t *buf[3];
 254                     buf[0] = buf[1] = buf[2] = NULL;
 255                     if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 256                     {
 257                         p_block->i_buffer = 0;
 258                         break;
 259                     }
 260                     mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 261                     mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 262                 }
 263                 p_sys->p_picture_to_destroy = p_pic;
 264
 265                 if ( p_sys->b_slice_i )
 266                 {
 267                     decoder_SynchroNewPicture( p_sys->p_synchro,
 268                         I_CODING_TYPE, 2, 0, 0,
 269                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 270                     decoder_SynchroDecode( p_sys->p_synchro );
 271                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 272                 }
 273             }
 274
 275             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
 276             {
 277                 p_sys->b_preroll = true;
 278             }
 279             else if( p_sys->b_preroll )
 280             {
 281                 p_sys->b_preroll = false;
 282                 /* Reset synchro */
 283                 decoder_SynchroReset( p_sys->p_synchro );
 284             }
 285
 286 #ifdef PIC_FLAG_PTS
 287             if( p_block->i_pts )
 288             {
 289                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 290
 291 #else /* New interface */
 292             if( p_block->i_pts || p_block->i_dts )
 293             {
 294                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
 295                                    (uint32_t)p_block->i_pts,
 296                                    (uint32_t)p_block->i_dts );
 297 #endif
 298                 p_sys->i_previous_pts = p_sys->i_current_pts;
 299                 p_sys->i_current_pts = p_block->i_pts;
 300                 p_sys->i_previous_dts = p_sys->i_current_dts;
 301                 p_sys->i_current_dts = p_block->i_dts;
 302             }
 303
 304             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 305                           p_block->p_buffer + p_block->i_buffer );
 306
 307             p_block->i_buffer = 0;
 308             break;
 309
 310 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
 311
 312         case STATE_SEQUENCE_MODIFIED:
 313             GetAR( p_dec );
 314             break;
 315 #endif
 316
 317         case STATE_SEQUENCE:
 318         {
 319             /* Initialize video output */
 320             uint8_t *buf[3];
 321             buf[0] = buf[1] = buf[2] = NULL;
 322
 323             GetAR( p_dec );
 324
 325             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 326
 327             /* Set the first 2 reference frames */
 328             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 329
 330             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 331             {
 332                 block_Release( p_block );
 333                 return NULL;
 334             }
 335
 336             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 337             mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 338
 339             /* This picture will never go through display_picture. */
 340             p_pic->date = 0;
 341
 342             /* For some reason, libmpeg2 will put this pic twice in
 343              * discard_picture. This can be considered a bug in libmpeg2. */
 344             p_dec->pf_picture_link( p_dec, p_pic );
 345
 346             if( p_sys->p_synchro )
 347             {
 348                 decoder_SynchroRelease( p_sys->p_synchro );
 349             }
 350             p_sys->p_synchro = decoder_SynchroInit( p_dec,
 351                 (uint32_t)((uint64_t)1001000000 * 27 /
 352                 p_sys->p_info->sequence->frame_period) );
 353             p_sys->b_after_sequence_header = 1;
 354         }
 355         break;
 356
 357         case STATE_PICTURE_2ND:
 358             p_sys->b_second_field = 1;
 359             break;
 360
 361         case STATE_PICTURE:
 362         {
 363             uint8_t *buf[3];
 364             mtime_t i_pts, i_dts;
 365             buf[0] = buf[1] = buf[2] = NULL;
 366
 367             if ( p_sys->b_after_sequence_header &&
 368                  ((p_sys->p_info->current_picture->flags &
 369                        PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
 370             {
 371                 /* Intra-slice refresh. Simulate a blank I picture. */
 372                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 373                 decoder_SynchroNewPicture( p_sys->p_synchro,
 374                     I_CODING_TYPE, 2, 0, 0,
 375                     p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 376                 decoder_SynchroDecode( p_sys->p_synchro );
 377                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 378                 p_sys->b_slice_i = 1;
 379             }
 380             p_sys->b_after_sequence_header = 0;
 381
 382 #ifdef PIC_FLAG_PTS
 383             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
 384                 ( ( p_sys->p_info->current_picture->pts ==
 385                     (uint32_t)p_sys->i_current_pts ) ?
 386                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 387             i_dts = 0;
 388
 389             /* Hack to handle demuxers which only have DTS timestamps */
 390             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 391             {
 392                 if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 393                     (p_sys->p_info->current_picture->flags &
 394                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 395                 {
 396                     i_pts = p_block->i_dts;
 397                 }
 398             }
 399             p_block->i_pts = p_block->i_dts = 0;
 400             /* End hack */
 401
 402 #else /* New interface */
 403
 404             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 405                 ( ( p_sys->p_info->current_picture->tag ==
 406                     (uint32_t)p_sys->i_current_pts ) ?
 407                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 408             i_dts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
 409                 ( ( p_sys->p_info->current_picture->tag2 ==
 410                     (uint32_t)p_sys->i_current_dts ) ?
 411                   p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
 412 #endif
 413
 414             /* If nb_fields == 1, it is a field picture, and it will be
 415              * followed by another field picture for which we won't call
 416              * decoder_SynchroNewPicture() because this would have other
 417              * problems, so we take it into account here.
 418              * This kind of sucks, but I didn't think better. --Meuuh
 419              */
 420             decoder_SynchroNewPicture( p_sys->p_synchro,
 421                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 422                 p_sys->p_info->current_picture->nb_fields == 1 ? 2 :
 423                 p_sys->p_info->current_picture->nb_fields, i_pts, i_dts,
 424                 p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 425
 426             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
 427                 !(p_sys->b_slice_i
 428                    && ((p_sys->p_info->current_picture->flags
 429                          & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P))
 430                    && !decoder_SynchroChoose( p_sys->p_synchro,
 431                               p_sys->p_info->current_picture->flags
 432                                 & PIC_MASK_CODING_TYPE,
 433                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
 434                               p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
 435             {
 436                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 437                 p_sys->b_skip = 1;
 438                 decoder_SynchroTrash( p_sys->p_synchro );
 439                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 440             }
 441             else
 442             {
 443                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 444                 p_sys->b_skip = 0;
 445                 decoder_SynchroDecode( p_sys->p_synchro );
 446
 447                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 448                 {
 449                     block_Release( p_block );
 450                     return NULL;
 451                 }
 452
 453                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 454                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 455             }
 456             if( p_sys->p_info->user_data_len > 2 )
 457             {
 458                 p_sys->i_cc_pts = i_pts;
 459                 p_sys->i_cc_dts = i_dts;
 460                 if( (p_sys->p_info->current_picture->flags
 461                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
 462                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
 463                 else if( (p_sys->p_info->current_picture->flags
 464                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 465                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
 466                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
 467
 468                 cc_Extract( &p_sys->cc, &p_sys->p_info->user_data[0], p_sys->p_info->user_data_len );
 469             }
 470         }
 471         break;
 472
 473         case STATE_END:
 474         case STATE_SLICE:
 475             p_pic = NULL;
 476             if( p_sys->p_info->display_fbuf
 477                 && p_sys->p_info->display_fbuf->id )
 478             {
 479                 p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;
 480
 481                 decoder_SynchroEnd( p_sys->p_synchro,
 482                             p_sys->p_info->display_picture->flags
 483                              & PIC_MASK_CODING_TYPE,
 484                             p_sys->b_garbage_pic );
 485                 p_sys->b_garbage_pic = 0;
 486
 487                 if( p_sys->p_picture_to_destroy != p_pic )
 488                 {
 489                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
 490                 }
 491                 else
 492                 {
 493                     p_sys->p_picture_to_destroy = NULL;
 494                     p_pic->date = 0;
 495                 }
 496             }
 497
 498             if( p_sys->p_info->discard_fbuf &&
 499                 p_sys->p_info->discard_fbuf->id )
 500             {
 501                 p_dec->pf_picture_unlink( p_dec,
 502                                           p_sys->p_info->discard_fbuf->id );
 503             }
 504
 505             /* For still frames */
 506             if( state == STATE_END && p_pic ) p_pic->b_force = true;
 507
 508             if( p_pic )
 509             {
 510                 /* Avoid frames with identical timestamps.
 511                  * Especially needed for still frames in DVD menus. */
 512                 if( p_sys->i_last_frame_pts == p_pic->date ) p_pic->date++;
 513                 p_sys->i_last_frame_pts = p_pic->date;
 514
 515                 return p_pic;
 516             }
 517             break;
 518
 519         case STATE_INVALID:
 520         {
 521             uint8_t *buf[3];
 522             buf[0] = buf[1] = buf[2] = NULL;
 523
 524             msg_Warn( p_dec, "invalid picture encountered" );
 525             if ( ( p_sys->p_info->current_picture == NULL ) ||
 526                ( ( p_sys->p_info->current_picture->flags &
 527                    PIC_MASK_CODING_TYPE) != PIC_FLAG_CODING_TYPE_B ) )
 528             {
 529                 if( p_sys->p_synchro ) decoder_SynchroReset( p_sys->p_synchro );
 530             }
 531             mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 532             p_sys->b_skip = 1;
 533             cc_Flush( &p_sys->cc );
 534
 535             if( p_sys->p_info->current_fbuf &&
 536                 p_sys->p_info->current_fbuf->id )
 537             {
 538                 p_sys->b_garbage_pic = 1;
 539                 p_pic = p_sys->p_info->current_fbuf->id;
 540             }
 541             else if( !p_sys->p_info->sequence )
 542             {
 543                 break;
 544             }
 545             else
 546             {
 547                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 548                     break;
 549                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 550                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
 551             }
 552             p_sys->p_picture_to_destroy = p_pic;
 553
 554             memset( p_pic->p[0].p_pixels, 0,
 555                     p_sys->p_info->sequence->width
 556                      * p_sys->p_info->sequence->height );
 557             memset( p_pic->p[1].p_pixels, 0x80,
 558                     p_sys->p_info->sequence->width
 559                      * p_sys->p_info->sequence->height / 4 );
 560             memset( p_pic->p[2].p_pixels, 0x80,
 561                     p_sys->p_info->sequence->width
 562                      * p_sys->p_info->sequence->height / 4 );
 563
 564             if( p_sys->b_slice_i )
 565             {
 566                 decoder_SynchroNewPicture( p_sys->p_synchro,
 567                         I_CODING_TYPE, 2, 0, 0,
 568                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
 569                 decoder_SynchroDecode( p_sys->p_synchro );
 570                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 571             }
 572             break;
 573         }
 574
 575         default:
 576             break;
 577         }
 578     }
 579
 580     /* Never reached */
 581     return NULL;
 582 }
 583
 584 /*****************************************************************************
 585  * CloseDecoder: libmpeg2 decoder destruction
 586  *****************************************************************************/
 587 static void CloseDecoder( vlc_object_t *p_this )
 588 {
 589     decoder_t *p_dec = (decoder_t *)p_this;
 590     decoder_sys_t *p_sys = p_dec->p_sys;
 591
 592     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
 593
 594     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 595
 596     free( p_sys );
 597 }
 598
 599 /*****************************************************************************
 600  * GetNewPicture: Get a new picture from the vout and set the buf struct
 601  *****************************************************************************/
 602 static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
 603 {
 604     decoder_sys_t *p_sys = p_dec->p_sys;
 605     picture_t *p_pic;
 606
 607     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 608     p_dec->fmt_out.video.i_visible_width =
 609         p_sys->p_info->sequence->picture_width;
 610     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 611     p_dec->fmt_out.video.i_visible_height =
 612         p_sys->p_info->sequence->picture_height;
 613     p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;
 614     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
 615     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
 616
 617     if( p_sys->p_info->sequence->frame_period > 0 )
 618     {
 619         p_dec->fmt_out.video.i_frame_rate =
 620             (uint32_t)( (uint64_t)1001000000 * 27 /
 621                         p_sys->p_info->sequence->frame_period );
 622         p_dec->fmt_out.video.i_frame_rate_base = 1001;
 623     }
 624
 625     p_dec->fmt_out.i_codec =
 626         ( p_sys->p_info->sequence->chroma_height <
 627           p_sys->p_info->sequence->height ) ?
 628         VLC_FOURCC('I','4','2','0') : VLC_FOURCC('I','4','2','2');
 629
 630     /* Get a new picture */
 631     p_pic = p_dec->pf_vout_buffer_new( p_dec );
 632
 633     if( p_pic == NULL ) return NULL;
 634
 635     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 636         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 637     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 638         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 639     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 640         p_sys->p_info->current_picture->nb_fields : 2;
 641
 642     p_dec->pf_picture_link( p_dec, p_pic );
 643
 644     pp_buf[0] = p_pic->p[0].p_pixels;
 645     pp_buf[1] = p_pic->p[1].p_pixels;
 646     pp_buf[2] = p_pic->p[2].p_pixels;
 647
 648     return p_pic;
 649 }
 650
 651 /*****************************************************************************
 652  * GetCc: Retrieves the Closed Captions for the CC decoder.
 653  *****************************************************************************/
 654 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
 655 {
 656     decoder_sys_t   *p_sys = p_dec->p_sys;
 657     block_t         *p_cc = NULL;
 658     int i;
 659
 660     for( i = 0; i < 4; i++ )
 661         pb_present[i] = p_sys->cc.pb_present[i];
 662
 663     if( p_sys->cc.i_data <= 0 )
 664         return NULL;
 665
 666     p_cc = block_New( p_dec, p_sys->cc.i_data);
 667     if( p_cc )
 668     {
 669         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
 670         p_cc->i_dts =
 671         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
 672         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);
 673     }
 674     cc_Flush( &p_sys->cc );
 675     return p_cc;
 676 }
 677
 678 /*****************************************************************************
 679  * GetAR: Get aspect ratio
 680  *****************************************************************************/
 681 static void GetAR( decoder_t *p_dec )
 682 {
 683     decoder_sys_t *p_sys = p_dec->p_sys;
 684
 685     /* Check whether the input gave a particular aspect ratio */
 686     if( p_dec->fmt_in.video.i_aspect )
 687     {
 688         p_sys->i_aspect = p_dec->fmt_in.video.i_aspect;
 689     }
 690     else
 691     {
 692         /* Use the value provided in the MPEG sequence header */
 693         if( p_sys->p_info->sequence->pixel_height > 0 )
 694         {
 695             p_sys->i_aspect =
 696                 ((uint64_t)p_sys->p_info->sequence->picture_width) *
 697                 p_sys->p_info->sequence->pixel_width *
 698                 VOUT_ASPECT_FACTOR /
 699                 p_sys->p_info->sequence->picture_height /
 700                 p_sys->p_info->sequence->pixel_height;
 701             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
 702             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
 703         }
 704         else
 705         {
 706             /* Invalid aspect, assume 4:3.
 707              * This shouldn't happen and if it does it is a bug
 708              * in libmpeg2 (likely triggered by an invalid stream) */
 709             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 710             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
 711             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
 712         }
 713     }
 714
 715     msg_Dbg( p_dec, "%dx%d (display %d,%d), aspect %d, sar %i:%i, %u.%03u fps",
 716              p_sys->p_info->sequence->picture_width,
 717              p_sys->p_info->sequence->picture_height,
 718              p_sys->p_info->sequence->display_width,
 719              p_sys->p_info->sequence->display_height,
 720              p_sys->i_aspect, p_sys->i_sar_num, p_sys->i_sar_den,
 721              (uint32_t)((uint64_t)1001000000 * 27 /
 722                  p_sys->p_info->sequence->frame_period / 1001),
 723              (uint32_t)((uint64_t)1001000000 * 27 /
 724                  p_sys->p_info->sequence->frame_period % 1001) );
 725 }