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 VideoLAN
   5  * $Id: libmpeg2.c,v 1.39 2003/12/22 14:32:55 sam Exp $
   6  *
   7  * Authors: Gildas Bazin <gbazin@netcourrier.com>
   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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #include <vlc/vlc.h>
  29 #include <vlc/vout.h>
  30 #include <vlc/decoder.h>
  31
  32 #include <mpeg2dec/mpeg2.h>
  33
  34 #include "vout_synchro.h"
  35
  36 /* Aspect ratio (ISO/IEC 13818-2 section 6.3.3, table 6-3) */
  37 #define AR_SQUARE_PICTURE       1                           /* square pixels */
  38 #define AR_3_4_PICTURE          2                        /* 3:4 picture (TV) */
  39 #define AR_16_9_PICTURE         3              /* 16:9 picture (wide screen) */
  40 #define AR_221_1_PICTURE        4                  /* 2.21:1 picture (movie) */
  41
  42 /*****************************************************************************
  43  * decoder_sys_t : libmpeg2 decoder descriptor
  44  *****************************************************************************/
  45 struct decoder_sys_t
  46 {
  47     /*
  48      * libmpeg2 properties
  49      */
  50     mpeg2dec_t          *p_mpeg2dec;
  51     const mpeg2_info_t  *p_info;
  52     vlc_bool_t          b_skip;
  53
  54     /*
  55      * Input properties
  56      */
  57     pes_packet_t     *p_pes;                  /* current PES we are decoding */
  58     mtime_t          i_pts;
  59     mtime_t          i_previous_pts;
  60     mtime_t          i_current_pts;
  61     int              i_current_rate;
  62     picture_t *      p_picture_to_destroy;
  63     vlc_bool_t       b_garbage_pic;
  64     vlc_bool_t       b_after_sequence_header; /* is it the next frame after
  65                                                * the sequence header ?    */
  66     vlc_bool_t       b_slice_i;             /* intra-slice refresh stream */
  67
  68     /*
  69      * Output properties
  70      */
  71     vout_synchro_t *p_synchro;
  72     int i_aspect;
  73
  74 };
  75
  76 /*****************************************************************************
  77  * Local prototypes
  78  *****************************************************************************/
  79 static int  OpenDecoder( vlc_object_t * );
  80 static void CloseDecoder( vlc_object_t * );
  81
  82 static picture_t *DecodeBlock( decoder_t *, block_t ** );
  83
  84 static picture_t *GetNewPicture( decoder_t *, uint8_t ** );
  85
  86 /*****************************************************************************
  87  * Module descriptor
  88  *****************************************************************************/
  89 vlc_module_begin();
  90     set_description( _("MPEG I/II video decoder (using libmpeg2)") );
  91     set_capability( "decoder", 150 );
  92     set_callbacks( OpenDecoder, CloseDecoder );
  93     add_shortcut( "libmpeg2" );
  94 vlc_module_end();
  95
  96 /*****************************************************************************
  97  * OpenDecoder: probe the decoder and return score
  98  *****************************************************************************/
  99 static int OpenDecoder( vlc_object_t *p_this )
 100 {
 101     decoder_t *p_dec = (decoder_t*)p_this;
 102     decoder_sys_t *p_sys;
 103
 104     if( p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','v') &&
 105         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','1') &&
 106         /* Pinnacle hardware-mpeg1 */
 107         p_dec->fmt_in.i_codec != VLC_FOURCC('P','I','M','1') &&
 108         /* ATI Video */
 109         p_dec->fmt_in.i_codec != VLC_FOURCC('V','C','R','2') &&
 110         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','2') )
 111     {
 112         return VLC_EGENERIC;
 113     }
 114
 115     /* Allocate the memory needed to store the decoder's structure */
 116     if( ( p_dec->p_sys = p_sys =
 117           (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
 118     {
 119         msg_Err( p_dec, "out of memory" );
 120         return VLC_EGENERIC;
 121     }
 122
 123     /* Initialize the thread properties */
 124     memset( p_sys, 0, sizeof(decoder_sys_t) );
 125     p_sys->p_pes      = NULL;
 126     p_sys->p_mpeg2dec = NULL;
 127     p_sys->p_synchro  = NULL;
 128     p_sys->p_info     = NULL;
 129     p_sys->i_pts      = mdate() + DEFAULT_PTS_DELAY;
 130     p_sys->i_current_pts  = 0;
 131     p_sys->i_previous_pts = 0;
 132     p_sys->p_picture_to_destroy = NULL;
 133     p_sys->b_garbage_pic = 0;
 134     p_sys->b_slice_i  = 0;
 135     p_sys->b_skip     = 0;
 136
 137     /* Initialize decoder */
 138     p_sys->p_mpeg2dec = mpeg2_init();
 139     if( p_sys->p_mpeg2dec == NULL)
 140     {
 141         msg_Err( p_dec, "mpeg2_init() failed" );
 142         free( p_sys );
 143         return VLC_EGENERIC;
 144     }
 145
 146     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
 147
 148     p_dec->pf_decode_video = DecodeBlock;
 149
 150     return VLC_SUCCESS;
 151 }
 152
 153 /*****************************************************************************
 154  * RunDecoder: the libmpeg2 decoder
 155  *****************************************************************************/
 156 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 157 {
 158     decoder_sys_t   *p_sys = p_dec->p_sys;
 159     mpeg2_state_t   state;
 160     picture_t       *p_pic;
 161
 162     block_t *p_block;
 163
 164     if( !pp_block || !*pp_block ) return NULL;
 165
 166     p_block = *pp_block;
 167
 168     while( 1 )
 169     {
 170         state = mpeg2_parse( p_sys->p_mpeg2dec );
 171
 172         switch( state )
 173         {
 174         case STATE_BUFFER:
 175             if( !p_block->i_buffer )
 176             {
 177                 block_Release( p_block );
 178                 return NULL;
 179             }
 180
 181             if( p_block->b_discontinuity && p_sys->p_synchro &&
 182                 p_sys->p_info->sequence &&
 183                 p_sys->p_info->sequence->width != (unsigned)-1 )
 184             {
 185                 vout_SynchroReset( p_sys->p_synchro );
 186                 if( p_sys->p_info->current_fbuf != NULL
 187                     && p_sys->p_info->current_fbuf->id != NULL )
 188                 {
 189                     p_sys->b_garbage_pic = 1;
 190                     p_pic = p_sys->p_info->current_fbuf->id;
 191                 }
 192                 else
 193                 {
 194                     uint8_t *buf[3];
 195                     buf[0] = buf[1] = buf[2] = NULL;
 196                     if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 197                         break;
 198                     mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 199                 }
 200                 p_sys->p_picture_to_destroy = p_pic;
 201
 202                 if ( p_sys->b_slice_i )
 203                 {
 204                     vout_SynchroNewPicture( p_sys->p_synchro,
 205                         I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate );
 206                     vout_SynchroDecode( p_sys->p_synchro );
 207                     vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 208                 }
 209             }
 210
 211             if( p_block->i_pts )
 212             {
 213                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
 214                 p_sys->i_previous_pts = p_sys->i_current_pts;
 215                 p_sys->i_current_pts = p_block->i_pts;
 216             }
 217
 218             p_sys->i_current_rate = DEFAULT_RATE;//p_pes->i_rate;
 219
 220             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
 221                           p_block->p_buffer + p_block->i_buffer );
 222
 223             p_block->i_buffer = 0;
 224             break;
 225
 226         case STATE_SEQUENCE:
 227         {
 228             /* Initialize video output */
 229             uint8_t *buf[3];
 230             buf[0] = buf[1] = buf[2] = NULL;
 231
 232             /* Check whether the input gave a particular aspect ratio */
 233             if( p_dec->fmt_in.video.i_aspect )
 234             {
 235                 p_sys->i_aspect = p_dec->fmt_in.video.i_aspect;
 236                 if( p_sys->i_aspect <= AR_221_1_PICTURE )
 237                 switch( p_sys->i_aspect )
 238                 {
 239                 case AR_3_4_PICTURE:
 240                     p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 241                     break;
 242                 case AR_16_9_PICTURE:
 243                     p_sys->i_aspect = VOUT_ASPECT_FACTOR * 16 / 9;
 244                     break;
 245                 case AR_221_1_PICTURE:
 246                     p_sys->i_aspect = VOUT_ASPECT_FACTOR * 221 / 100;
 247                     break;
 248                 case AR_SQUARE_PICTURE:
 249                     p_sys->i_aspect = VOUT_ASPECT_FACTOR *
 250                                    p_sys->p_info->sequence->width /
 251                                    p_sys->p_info->sequence->height;
 252                     break;
 253                 }
 254             }
 255             else
 256             {
 257                 /* Use the value provided in the MPEG sequence header */
 258                 p_sys->i_aspect =
 259                     ((uint64_t)p_sys->p_info->sequence->display_width) *
 260                     p_sys->p_info->sequence->pixel_width * VOUT_ASPECT_FACTOR /
 261                     p_sys->p_info->sequence->display_height /
 262                     p_sys->p_info->sequence->pixel_height;
 263             }
 264
 265             msg_Dbg( p_dec, "%dx%d, aspect %d, %u.%03u fps",
 266                      p_sys->p_info->sequence->width,
 267                      p_sys->p_info->sequence->height, p_sys->i_aspect,
 268                      (uint32_t)((uint64_t)1001000000 * 27 /
 269                          p_sys->p_info->sequence->frame_period / 1001),
 270                      (uint32_t)((uint64_t)1001000000 * 27 /
 271                          p_sys->p_info->sequence->frame_period % 1001) );
 272
 273             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
 274
 275             /* Set the first 2 reference frames */
 276             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 277
 278             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 279             {
 280                 block_Release( p_block );
 281                 return NULL;
 282             }
 283
 284             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 285
 286             /* This picture will never go through display_picture. */
 287             p_pic->date = 0;
 288
 289             /* For some reason, libmpeg2 will put this pic twice in
 290              * discard_picture. This can be considered a bug in libmpeg2. */
 291             p_dec->pf_picture_link( p_dec, p_pic );
 292
 293             if( p_sys->p_synchro )
 294             {
 295                 vout_SynchroRelease( p_sys->p_synchro );
 296             }
 297             p_sys->p_synchro = vout_SynchroInit( p_dec,
 298                 (uint32_t)((uint64_t)1001000000 * 27 /
 299                 p_sys->p_info->sequence->frame_period) );
 300             p_sys->b_after_sequence_header = 1;
 301         }
 302         break;
 303
 304         case STATE_PICTURE_2ND:
 305             vout_SynchroNewPicture( p_sys->p_synchro,
 306                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 307                 p_sys->p_info->current_picture->nb_fields,
 308                 0, 0, p_sys->i_current_rate );
 309
 310             if( p_sys->b_skip )
 311             {
 312                 vout_SynchroTrash( p_sys->p_synchro );
 313             }
 314             else
 315             {
 316                 vout_SynchroDecode( p_sys->p_synchro );
 317             }
 318             break;
 319
 320         case STATE_PICTURE:
 321         {
 322             uint8_t *buf[3];
 323             mtime_t i_pts;
 324             buf[0] = buf[1] = buf[2] = NULL;
 325
 326             if ( p_sys->b_after_sequence_header &&
 327                  ((p_sys->p_info->current_picture->flags &
 328                        PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
 329             {
 330                 /* Intra-slice refresh. Simulate a blank I picture. */
 331                 msg_Dbg( p_dec, "intra-slice refresh stream" );
 332                 vout_SynchroNewPicture( p_sys->p_synchro,
 333                     I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate );
 334                 vout_SynchroDecode( p_sys->p_synchro );
 335                 vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 336                 p_sys->b_slice_i = 1;
 337             }
 338             p_sys->b_after_sequence_header = 0;
 339
 340             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
 341                 ( ( p_sys->p_info->current_picture->pts ==
 342                     (uint32_t)p_sys->i_current_pts ) ?
 343                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
 344
 345             /* Hack to handle demuxers which only have DTS timestamps */
 346             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
 347             {
 348                 if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
 349                     (p_sys->p_info->current_picture->flags &
 350                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
 351                 {
 352                     i_pts = p_block->i_dts;
 353                 }
 354             }
 355             p_block->i_pts = p_block->i_dts = 0;
 356             /* End hack */
 357
 358             vout_SynchroNewPicture( p_sys->p_synchro,
 359                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 360                 p_sys->p_info->current_picture->nb_fields, i_pts,
 361                 0, p_sys->i_current_rate );
 362
 363             if ( !(p_sys->b_slice_i
 364                    && ((p_sys->p_info->current_picture->flags
 365                          & PIC_MASK_CODING_TYPE) == P_CODING_TYPE))
 366                    && !vout_SynchroChoose( p_sys->p_synchro,
 367                               p_sys->p_info->current_picture->flags
 368                                 & PIC_MASK_CODING_TYPE,
 369                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/ ) )
 370             {
 371                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 372                 p_sys->b_skip = 1;
 373                 vout_SynchroTrash( p_sys->p_synchro );
 374                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
 375             }
 376             else
 377             {
 378                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
 379                 p_sys->b_skip = 0;
 380                 vout_SynchroDecode( p_sys->p_synchro );
 381
 382                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 383                 {
 384                     block_Release( p_block );
 385                     return NULL;
 386                 }
 387
 388                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 389             }
 390         }
 391         break;
 392
 393         case STATE_END:
 394         case STATE_SLICE:
 395             p_pic = NULL;
 396             if( p_sys->p_info->display_fbuf
 397                 && p_sys->p_info->display_fbuf->id )
 398             {
 399                 p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;
 400
 401                 vout_SynchroEnd( p_sys->p_synchro,
 402                             p_sys->p_info->display_picture->flags
 403                              & PIC_MASK_CODING_TYPE,
 404                             p_sys->b_garbage_pic );
 405                 p_sys->b_garbage_pic = 0;
 406
 407                 if ( p_sys->p_picture_to_destroy != p_pic )
 408                 {
 409                     p_pic->date = vout_SynchroDate( p_sys->p_synchro );
 410                 }
 411                 else
 412                 {
 413                     p_sys->p_picture_to_destroy = NULL;
 414                     p_pic->date = 0;
 415                 }
 416             }
 417
 418             if( p_sys->p_info->discard_fbuf &&
 419                 p_sys->p_info->discard_fbuf->id )
 420             {
 421                 p_dec->pf_picture_unlink( p_dec,
 422                                           p_sys->p_info->discard_fbuf->id );
 423             }
 424
 425             if( p_pic ) return p_pic;
 426
 427             break;
 428
 429         case STATE_INVALID:
 430         {
 431             uint8_t *buf[3];
 432             buf[0] = buf[1] = buf[2] = NULL;
 433
 434             msg_Warn( p_dec, "invalid picture encountered" );
 435             if ( ( p_sys->p_info->current_picture == NULL ) ||
 436                ( ( p_sys->p_info->current_picture->flags &
 437                    PIC_MASK_CODING_TYPE) != B_CODING_TYPE ) )
 438             {
 439                 if( p_sys->p_synchro ) vout_SynchroReset( p_sys->p_synchro );
 440             }
 441             mpeg2_skip( p_sys->p_mpeg2dec, 1 );
 442             p_sys->b_skip = 1;
 443
 444             if( p_sys->p_info->current_fbuf &&
 445                 p_sys->p_info->current_fbuf->id )
 446             {
 447                 p_sys->b_garbage_pic = 1;
 448                 p_pic = p_sys->p_info->current_fbuf->id;
 449             }
 450             else if( !p_sys->p_info->sequence )
 451             {
 452                 break;
 453             }
 454             else
 455             {
 456                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
 457                     break;
 458                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
 459             }
 460             p_sys->p_picture_to_destroy = p_pic;
 461
 462             memset( p_pic->p[0].p_pixels, 0,
 463                     p_sys->p_info->sequence->width
 464                      * p_sys->p_info->sequence->height );
 465             memset( p_pic->p[1].p_pixels, 0x80,
 466                     p_sys->p_info->sequence->width
 467                      * p_sys->p_info->sequence->height / 4 );
 468             memset( p_pic->p[2].p_pixels, 0x80,
 469                     p_sys->p_info->sequence->width
 470                      * p_sys->p_info->sequence->height / 4 );
 471
 472             if( p_sys->b_slice_i )
 473             {
 474                 vout_SynchroNewPicture( p_sys->p_synchro,
 475                             I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate );
 476                 vout_SynchroDecode( p_sys->p_synchro );
 477                 vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
 478             }
 479             break;
 480         }
 481
 482         default:
 483             break;
 484         }
 485     }
 486
 487     /* Never reached */
 488     return NULL;
 489 }
 490
 491 /*****************************************************************************
 492  * CloseDecoder: libmpeg2 decoder destruction
 493  *****************************************************************************/
 494 static void CloseDecoder( vlc_object_t *p_this )
 495 {
 496     decoder_t *p_dec = (decoder_t *)p_this;
 497     decoder_sys_t *p_sys = p_dec->p_sys;
 498
 499     if( p_sys->p_synchro ) vout_SynchroRelease( p_sys->p_synchro );
 500
 501     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
 502
 503     free( p_sys );
 504 }
 505
 506 /*****************************************************************************
 507  * GetNewPicture: Get a new picture from the vout and set the buf struct
 508  *****************************************************************************/
 509 static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
 510 {
 511     decoder_sys_t *p_sys = p_dec->p_sys;
 512     picture_t *p_pic;
 513
 514     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
 515     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
 516     p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;
 517
 518     p_dec->fmt_out.i_codec =
 519         ( p_sys->p_info->sequence->chroma_height <
 520           p_sys->p_info->sequence->height ) ?
 521         VLC_FOURCC('I','4','2','0') : VLC_FOURCC('I','4','2','2');
 522
 523     /* Get a new picture */
 524     p_pic = p_dec->pf_vout_buffer_new( p_dec );
 525
 526     if( p_pic == NULL ) return NULL;
 527
 528     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
 529         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
 530     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
 531         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
 532     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
 533         p_sys->p_info->current_picture->nb_fields : 2;
 534
 535     p_dec->pf_picture_link( p_dec, p_pic );
 536
 537     pp_buf[0] = p_pic->p[0].p_pixels;
 538     pp_buf[1] = p_pic->p[1].p_pixels;
 539     pp_buf[2] = p_pic->p[2].p_pixels;
 540
 541     return p_pic;
 542 }