git.sesse.net Git - vlc/blob - src/spu_decoder/spu_decoder.c

   1 /*****************************************************************************
   2  * spu_decoder.c : spu decoder thread
   3  *****************************************************************************
   4  * Copyright (C) 2000 VideoLAN
   5  * $Id: spu_decoder.c,v 1.38 2001/04/28 03:36:25 sam Exp $
   6  *
   7  * Authors: Samuel Hocevar <sam@zoy.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include "defs.h"
  28
  29 #include <unistd.h>                                              /* getpid() */
  30 #ifdef WIN32                   /* getpid() for win32 is located in process.h */
  31 #include <process.h>
  32 #endif
  33
  34 #include <stdlib.h>                                      /* malloc(), free() */
  35 #include <string.h>                                    /* memcpy(), memset() */
  36
  37 #include "config.h"
  38 #include "common.h"
  39 #include "threads.h"
  40 #include "mtime.h"
  41
  42 #include "intf_msg.h"
  43
  44 #include "stream_control.h"
  45 #include "input_ext-dec.h"
  46
  47 #include "video.h"
  48 #include "video_output.h"
  49
  50 #include "spu_decoder.h"
  51
  52 /*****************************************************************************
  53  * Local prototypes
  54  *****************************************************************************/
  55 static int  InitThread  ( spudec_thread_t * );
  56 static void RunThread   ( spudec_thread_t * );
  57 static void ErrorThread ( spudec_thread_t * );
  58 static void EndThread   ( spudec_thread_t * );
  59
  60 static int  SyncPacket           ( spudec_thread_t * );
  61 static void ParsePacket          ( spudec_thread_t * );
  62 static int  ParseControlSequences( spudec_thread_t *, subpicture_t * );
  63 static int  ParseRLE             ( u8 *,              subpicture_t * );
  64
  65 /*****************************************************************************
  66  * spudec_CreateThread: create a spu decoder thread
  67  *****************************************************************************/
  68 vlc_thread_t spudec_CreateThread( vdec_config_t * p_config )
  69 {
  70     spudec_thread_t *     p_spudec;
  71
  72     /* Allocate the memory needed to store the thread's structure */
  73     p_spudec = (spudec_thread_t *)malloc( sizeof(spudec_thread_t) );
  74
  75     if ( p_spudec == NULL )
  76     {
  77         intf_ErrMsg( "spudec error: not enough memory "
  78                      "for spudec_CreateThread() to create the new thread" );
  79         return( 0 );
  80     }
  81
  82     /*
  83      * Initialize the thread properties
  84      */
  85     p_spudec->p_config = p_config;
  86     p_spudec->p_fifo = p_config->decoder_config.p_decoder_fifo;
  87
  88     /* Get the video output informations */
  89     p_spudec->p_vout = p_config->p_vout;
  90
  91     /* Spawn the spu decoder thread */
  92     if ( vlc_thread_create(&p_spudec->thread_id, "spu decoder",
  93          (vlc_thread_func_t)RunThread, (void *)p_spudec) )
  94     {
  95         intf_ErrMsg( "spudec error: can't spawn spu decoder thread" );
  96         free( p_spudec );
  97         return( 0 );
  98     }
  99
 100     return( p_spudec->thread_id );
 101 }
 102
 103 /* following functions are local */
 104
 105 /*****************************************************************************
 106  * InitThread: initialize spu decoder thread
 107  *****************************************************************************
 108  * This function is called from RunThread and performs the second step of the
 109  * initialization. It returns 0 on success. Note that the thread's flag are not
 110  * modified inside this function.
 111  *****************************************************************************/
 112 static int InitThread( spudec_thread_t *p_spudec )
 113 {
 114     p_spudec->p_config->decoder_config.pf_init_bit_stream(
 115             &p_spudec->bit_stream,
 116             p_spudec->p_config->decoder_config.p_decoder_fifo, NULL, NULL );
 117
 118     /* Mark thread as running and return */
 119     return( 0 );
 120 }
 121
 122 /*****************************************************************************
 123  * RunThread: spu decoder thread
 124  *****************************************************************************
 125  * spu decoder thread. This function only returns when the thread is
 126  * terminated.
 127  *****************************************************************************/
 128 static void RunThread( spudec_thread_t *p_spudec )
 129 {
 130     intf_WarnMsg( 1, "spudec: spu decoder thread %i spawned", getpid() );
 131
 132     /*
 133      * Initialize thread and free configuration
 134      */
 135     p_spudec->p_fifo->b_error = InitThread( p_spudec );
 136
 137     /*
 138      * Main loop - it is not executed if an error occured during
 139      * initialization
 140      */
 141     while( (!p_spudec->p_fifo->b_die) && (!p_spudec->p_fifo->b_error) )
 142     {
 143         if( !SyncPacket( p_spudec ) )
 144         {
 145             ParsePacket( p_spudec );
 146         }
 147     }
 148
 149     /*
 150      * Error loop
 151      */
 152     if( p_spudec->p_fifo->b_error )
 153     {
 154         ErrorThread( p_spudec );
 155     }
 156
 157     /* End of thread */
 158     intf_WarnMsg( 1, "spudec: destroying spu decoder thread %i", getpid() );
 159     EndThread( p_spudec );
 160 }
 161
 162 /*****************************************************************************
 163  * ErrorThread: RunThread() error loop
 164  *****************************************************************************
 165  * This function is called when an error occured during thread main's loop. The
 166  * thread can still receive feed, but must be ready to terminate as soon as
 167  * possible.
 168  *****************************************************************************/
 169 static void ErrorThread( spudec_thread_t *p_spudec )
 170 {
 171     /* We take the lock, because we are going to read/write the start/end
 172      * indexes of the decoder fifo */
 173     vlc_mutex_lock( &p_spudec->p_fifo->data_lock );
 174
 175     /* Wait until a `die' order is sent */
 176     while( !p_spudec->p_fifo->b_die )
 177     {
 178         /* Trash all received PES packets */
 179         while( !DECODER_FIFO_ISEMPTY(*p_spudec->p_fifo) )
 180         {
 181             p_spudec->p_fifo->pf_delete_pes( p_spudec->p_fifo->p_packets_mgt,
 182                     DECODER_FIFO_START(*p_spudec->p_fifo) );
 183             DECODER_FIFO_INCSTART( *p_spudec->p_fifo );
 184         }
 185
 186         /* Waiting for the input thread to put new PES packets in the fifo */
 187         vlc_cond_wait( &p_spudec->p_fifo->data_wait,
 188                        &p_spudec->p_fifo->data_lock );
 189     }
 190
 191     /* We can release the lock before leaving */
 192     vlc_mutex_unlock( &p_spudec->p_fifo->data_lock );
 193 }
 194
 195 /*****************************************************************************
 196  * EndThread: thread destruction
 197  *****************************************************************************
 198  * This function is called when the thread ends after a sucessful
 199  * initialization.
 200  *****************************************************************************/
 201 static void EndThread( spudec_thread_t *p_spudec )
 202 {
 203     free( p_spudec->p_config );
 204     free( p_spudec );
 205 }
 206
 207 /*****************************************************************************
 208  * SyncPacket: get in sync with the stream
 209  *****************************************************************************
 210  * This function makes a few sanity checks and returns 0 if it looks like we
 211  * are at the beginning of a subpicture packet.
 212  *****************************************************************************/
 213 static int SyncPacket( spudec_thread_t *p_spudec )
 214 {
 215     /* Re-align the buffer on an 8-bit boundary */
 216     RealignBits( &p_spudec->bit_stream );
 217
 218     /* The total SPU packet size, often bigger than a PS packet */
 219     p_spudec->i_spu_size = GetBits( &p_spudec->bit_stream, 16 );
 220
 221     /* The RLE stuff size (remove 4 because we just read 32 bits) */
 222     p_spudec->i_rle_size = ShowBits( &p_spudec->bit_stream, 16 ) - 4;
 223
 224     /* If the values we got are a bit strange, skip packet */
 225     if( p_spudec->i_rle_size >= p_spudec->i_spu_size )
 226     {
 227         return( 1 );
 228     }
 229
 230     RemoveBits( &p_spudec->bit_stream, 16 );
 231
 232     return( 0 );
 233 }
 234
 235 /*****************************************************************************
 236  * ParsePacket: parse an SPU packet and send it to the video output
 237  *****************************************************************************
 238  * This function parses the SPU packet and, if valid, sends it to the
 239  * video output.
 240  *****************************************************************************/
 241 static void ParsePacket( spudec_thread_t *p_spudec )
 242 {
 243     subpicture_t * p_spu;
 244     u8           * p_src;
 245
 246     /* We cannot display a subpicture with no date */
 247     if( DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts == 0 )
 248     {
 249         return;
 250     }
 251
 252     /* Allocate the subpicture internal data. */
 253     p_spu = vout_CreateSubPicture( p_spudec->p_vout, DVD_SUBPICTURE,
 254                                    p_spudec->i_rle_size * 4 );
 255     /* Rationale for the "p_spudec->i_rle_size * 4": we are going to
 256      * expand the RLE stuff so that we won't need to read nibbles later
 257      * on. This will speed things up a lot. Plus, we'll only need to do
 258      * this stupid interlacing stuff once. */
 259
 260     if( p_spu == NULL )
 261     {
 262         return;
 263     }
 264
 265     /* Get display time now. If we do it later, we may miss a PTS. */
 266     p_spu->begin_date = p_spu->end_date
 267                     = DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts;
 268
 269     /* Allocate the temporary buffer we will parse */
 270     p_src = malloc( p_spudec->i_rle_size );
 271
 272     if( p_src == NULL )
 273     {
 274         intf_ErrMsg( "spudec error: could not allocate p_src" );
 275         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 276         return;
 277     }
 278
 279     /* Get RLE data */
 280     GetChunk( &p_spudec->bit_stream, p_src, p_spudec->i_rle_size );
 281
 282 #if 0
 283     /* Dump the subtitle info */
 284     intf_WarnHexDump( 0, p_spu->p_data, p_spudec->i_rle_size );
 285 #endif
 286
 287     /* Getting the control part */
 288     if( ParseControlSequences( p_spudec, p_spu ) )
 289     {
 290         /* There was a parse error, delete the subpicture */
 291         free( p_src );
 292         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 293         return;
 294     }
 295
 296     if( ParseRLE( p_src, p_spu ) )
 297     {
 298         /* There was a parse error, delete the subpicture */
 299         free( p_src );
 300         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 301         return;
 302     }
 303
 304     intf_WarnMsg( 1, "spudec: got a valid %ix%i subtitle at (%i,%i), "
 305                      "RLE offsets: 0x%x 0x%x",
 306                   p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y,
 307                   p_spu->type.spu.i_offset[0], p_spu->type.spu.i_offset[1] );
 308
 309     /* SPU is finished - we can ask the video output to display it */
 310     vout_DisplaySubPicture( p_spudec->p_vout, p_spu );
 311
 312     /* Clean up */
 313     free( p_src );
 314 }
 315
 316 /*****************************************************************************
 317  * ParseControlSequences: parse all SPU control sequences
 318  *****************************************************************************
 319  * This is the most important part in SPU decoding. We get dates, palette
 320  * information, coordinates, and so on. For more information on the
 321  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 322  *****************************************************************************/
 323 static int ParseControlSequences( spudec_thread_t *p_spudec,
 324                                   subpicture_t * p_spu )
 325 {
 326     /* Our current index in the SPU packet */
 327     int i_index = p_spudec->i_rle_size + 4;
 328
 329     /* The next start-of-control-sequence index and the previous one */
 330     int i_next_index = 0, i_prev_index;
 331
 332     /* Command time and date */
 333     u8  i_command;
 334     int i_date;
 335
 336     do
 337     {
 338         /* Get the control sequence date */
 339         i_date = GetBits( &p_spudec->bit_stream, 16 );
 340
 341         /* Next offset */
 342         i_prev_index = i_next_index;
 343         i_next_index = GetBits( &p_spudec->bit_stream, 16 );
 344
 345         /* Skip what we just read */
 346         i_index += 4;
 347
 348         do
 349         {
 350             i_command = GetBits( &p_spudec->bit_stream, 8 );
 351             i_index++;
 352
 353             switch( i_command )
 354             {
 355                 case SPU_CMD_FORCE_DISPLAY:
 356
 357                     /* 00 (force displaying) */
 358                     break;
 359
 360                 /* Convert the dates in seconds to PTS values */
 361                 case SPU_CMD_START_DISPLAY:
 362
 363                     /* 01 (start displaying) */
 364                     p_spu->begin_date += ( i_date * 11000 );
 365
 366                     break;
 367
 368                 case SPU_CMD_STOP_DISPLAY:
 369
 370                     /* 02 (stop displaying) */
 371                     p_spu->end_date += ( i_date * 11000 );
 372
 373                     break;
 374
 375                 case SPU_CMD_SET_PALETTE:
 376
 377                     /* 03xxxx (palette) - trashed */
 378                     RemoveBits( &p_spudec->bit_stream, 16 );
 379                     i_index += 2;
 380
 381                     break;
 382
 383                 case SPU_CMD_SET_ALPHACHANNEL:
 384
 385                     /* 04xxxx (alpha channel) - trashed */
 386                     RemoveBits( &p_spudec->bit_stream, 16 );
 387                     i_index += 2;
 388
 389                     break;
 390
 391                 case SPU_CMD_SET_COORDINATES:
 392
 393                     /* 05xxxyyyxxxyyy (coordinates) */
 394                     p_spu->i_x = GetBits( &p_spudec->bit_stream, 12 );
 395                     p_spu->i_width = GetBits( &p_spudec->bit_stream, 12 )
 396                                       - p_spu->i_x + 1;
 397
 398                     p_spu->i_y = GetBits( &p_spudec->bit_stream, 12 );
 399                     p_spu->i_height = GetBits( &p_spudec->bit_stream, 12 )
 400                                        - p_spu->i_y + 1;
 401
 402                     i_index += 6;
 403
 404                     break;
 405
 406                 case SPU_CMD_SET_OFFSETS:
 407
 408                     /* 06xxxxyyyy (byte offsets) */
 409                     p_spu->type.spu.i_offset[0] =
 410                         GetBits( &p_spudec->bit_stream, 16 ) - 4;
 411
 412                     p_spu->type.spu.i_offset[1] =
 413                         GetBits( &p_spudec->bit_stream, 16 ) - 4;
 414
 415                     i_index += 4;
 416
 417                     break;
 418
 419                 case SPU_CMD_END:
 420
 421                     /* ff (end) */
 422                     break;
 423
 424                 default:
 425
 426                     /* xx (unknown command) */
 427                     intf_ErrMsg( "spudec error: unknown command 0x%.2x",
 428                                  i_command );
 429                     return( 1 );
 430             }
 431
 432         } while( i_command != SPU_CMD_END );
 433
 434     } while( i_index == i_next_index );
 435
 436     /* Check that the last index matches the previous one */
 437     if( i_next_index != i_prev_index )
 438     {
 439         intf_ErrMsg( "spudec error: index mismatch (0x%.4x != 0x%.4x)",
 440                      i_next_index, i_prev_index );
 441         return( 1 );
 442     }
 443
 444     if( i_index > p_spudec->i_spu_size )
 445     {
 446         intf_ErrMsg( "spudec error: uh-oh, we went too far (0x%.4x > 0x%.4x)",
 447                      i_index, p_spudec->i_spu_size );
 448         return( 1 );
 449     }
 450
 451     /* Get rid of padding bytes */
 452     switch( p_spudec->i_spu_size - i_index )
 453     {
 454         case 1:
 455
 456             RemoveBits( &p_spudec->bit_stream, 8 );
 457             i_index++;
 458
 459         case 0:
 460
 461             /* Zero or one padding byte, quite usual */
 462
 463             break;
 464
 465         default:
 466
 467             /* More than one padding byte - this is very strange, but
 468              * we can deal with it */
 469             intf_WarnMsg( 2, "spudec warning: %i padding bytes, we usually "
 470                              "get 1 or none",
 471                           p_spudec->i_spu_size - i_index );
 472
 473             while( i_index < p_spudec->i_spu_size )
 474             {
 475                 RemoveBits( &p_spudec->bit_stream, 8 );
 476                 i_index++;
 477             }
 478
 479             break;
 480     }
 481
 482     /* Successfully parsed ! */
 483     return( 0 );
 484 }
 485
 486 /*****************************************************************************
 487  * ParseRLE: parse the RLE part of the subtitle
 488  *****************************************************************************
 489  * This part parses the subtitle graphical data and stores it in a more
 490  * convenient structure for later decoding. For more information on the
 491  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 492  *****************************************************************************/
 493 static int ParseRLE( u8 *p_src, subpicture_t * p_spu )
 494 {
 495     unsigned int i_code;
 496     unsigned int i_id = 0;
 497
 498     unsigned int i_width = p_spu->i_width;
 499     unsigned int i_height = p_spu->i_height;
 500     unsigned int i_x, i_y;
 501
 502     u16 *p_dest = (u16 *)p_spu->p_data;
 503
 504     /* The subtitles are interlaced, we need two offsets */
 505     unsigned int  pi_table[ 2 ];
 506     unsigned int *pi_offset;
 507
 508     pi_table[ 0 ] = p_spu->type.spu.i_offset[ 0 ] << 1;
 509     pi_table[ 1 ] = p_spu->type.spu.i_offset[ 1 ] << 1;
 510
 511     for( i_y = 0 ; i_y < i_height ; i_y++ )
 512     {
 513         pi_offset = pi_table + i_id;
 514
 515         for( i_x = 0 ; i_x < i_width ; i_x += i_code >> 2 )
 516         {
 517             i_code = AddNibble( 0, p_src, pi_offset );
 518
 519             if( i_code < 0x04 )
 520             {
 521                 i_code = AddNibble( i_code, p_src, pi_offset );
 522
 523                 if( i_code < 0x10 )
 524                 {
 525                     i_code = AddNibble( i_code, p_src, pi_offset );
 526
 527                     if( i_code < 0x040 )
 528                     {
 529                         i_code = AddNibble( i_code, p_src, pi_offset );
 530
 531                         if( i_code < 0x0100 )
 532                         {
 533                             /* If the 14 first bits are set to 0, then it's a
 534                              * new line. We emulate it. */
 535                             if( i_code < 0x0004 )
 536                             {
 537                                 i_code |= ( i_width - i_x ) << 2;
 538                             }
 539                             else
 540                             {
 541                                 /* We have a boo boo ! */
 542                                 intf_ErrMsg( "spudec error: unknown RLE code "
 543                                              "0x%.4x", i_code );
 544                                 return( 1 );
 545                             }
 546                         }
 547                     }
 548                 }
 549             }
 550
 551             if( ( (i_code >> 2) + i_x + i_y * i_width ) > i_height * i_width )
 552             {
 553                 intf_ErrMsg( "spudec error: out of bounds, %i at (%i,%i) is "
 554                              "out of %ix%i",
 555                              i_code >> 2, i_x, i_y, i_width, i_height);
 556                 return( 1 );
 557             }
 558
 559             /* We got a valid code, store it */
 560             *p_dest++ = i_code;
 561         }
 562
 563         /* Check that we didn't go too far */
 564         if( i_x > i_width )
 565         {
 566             intf_ErrMsg( "spudec error: i_x overflowed, %i > %i",
 567                          i_x, i_width );
 568             return( 1 );
 569         }
 570
 571         /* Byte-align the stream */
 572         if( *pi_offset & 0x1 )
 573         {
 574             (*pi_offset)++;
 575         }
 576
 577         /* Swap fields */
 578         i_id = ~i_id & 0x1;
 579     }
 580
 581     /* FIXME: we shouldn't need these padding bytes */
 582     while( i_y < i_height )
 583     {
 584         *p_dest++ = i_width << 2;
 585         i_y++;
 586     }
 587
 588     return( 0 );
 589 }
 590