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 1.39 2001/05/01 12:22:18 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 #include "main.h" /* XXX: remove this later */
  53
  54 /*****************************************************************************
  55  * Local prototypes
  56  *****************************************************************************/
  57 static int  InitThread  ( spudec_thread_t * );
  58 static void RunThread   ( spudec_thread_t * );
  59 static void ErrorThread ( spudec_thread_t * );
  60 static void EndThread   ( spudec_thread_t * );
  61
  62 static int  SyncPacket           ( spudec_thread_t * );
  63 static void ParsePacket          ( spudec_thread_t * );
  64 static int  ParseControlSequences( spudec_thread_t *, subpicture_t * );
  65 static int  ParseRLE             ( u8 *,              subpicture_t * );
  66
  67 /*****************************************************************************
  68  * spudec_CreateThread: create a spu decoder thread
  69  *****************************************************************************/
  70 vlc_thread_t spudec_CreateThread( vdec_config_t * p_config )
  71 {
  72     spudec_thread_t *     p_spudec;
  73
  74     /* Allocate the memory needed to store the thread's structure */
  75     p_spudec = (spudec_thread_t *)malloc( sizeof(spudec_thread_t) );
  76
  77     if ( p_spudec == NULL )
  78     {
  79         intf_ErrMsg( "spudec error: not enough memory "
  80                      "for spudec_CreateThread() to create the new thread" );
  81         return( 0 );
  82     }
  83
  84     /*
  85      * Initialize the thread properties
  86      */
  87     p_spudec->p_config = p_config;
  88
  89     p_spudec->p_fifo = p_config->decoder_config.p_decoder_fifo;
  90
  91     /* XXX: The vout request and fifo opening will eventually be here */
  92     if( p_spudec->p_vout == NULL )
  93     {
  94         if( p_main->p_vout == NULL )
  95         {
  96             intf_Msg( "vpar: no vout present, spawning one" );
  97             p_main->p_vout = vout_CreateThread( NULL );
  98         }
  99
 100         p_spudec->p_vout = p_main->p_vout;
 101     }
 102
 103     /* Spawn the spu decoder thread */
 104     if ( vlc_thread_create(&p_spudec->thread_id, "spu decoder",
 105          (vlc_thread_func_t)RunThread, (void *)p_spudec) )
 106     {
 107         intf_ErrMsg( "spudec error: can't spawn spu decoder thread" );
 108         free( p_spudec );
 109         return( 0 );
 110     }
 111
 112     return( p_spudec->thread_id );
 113 }
 114
 115 /* following functions are local */
 116
 117 /*****************************************************************************
 118  * InitThread: initialize spu decoder thread
 119  *****************************************************************************
 120  * This function is called from RunThread and performs the second step of the
 121  * initialization. It returns 0 on success. Note that the thread's flag are not
 122  * modified inside this function.
 123  *****************************************************************************/
 124 static int InitThread( spudec_thread_t *p_spudec )
 125 {
 126     p_spudec->p_config->decoder_config.pf_init_bit_stream(
 127             &p_spudec->bit_stream,
 128             p_spudec->p_config->decoder_config.p_decoder_fifo, NULL, NULL );
 129
 130     /* Mark thread as running and return */
 131     return( 0 );
 132 }
 133
 134 /*****************************************************************************
 135  * RunThread: spu decoder thread
 136  *****************************************************************************
 137  * spu decoder thread. This function only returns when the thread is
 138  * terminated.
 139  *****************************************************************************/
 140 static void RunThread( spudec_thread_t *p_spudec )
 141 {
 142     intf_WarnMsg( 1, "spudec: spu decoder thread %i spawned", getpid() );
 143
 144     /*
 145      * Initialize thread and free configuration
 146      */
 147     p_spudec->p_fifo->b_error = InitThread( p_spudec );
 148
 149     /*
 150      * Main loop - it is not executed if an error occured during
 151      * initialization
 152      */
 153     while( (!p_spudec->p_fifo->b_die) && (!p_spudec->p_fifo->b_error) )
 154     {
 155         if( !SyncPacket( p_spudec ) )
 156         {
 157             ParsePacket( p_spudec );
 158         }
 159     }
 160
 161     /*
 162      * Error loop
 163      */
 164     if( p_spudec->p_fifo->b_error )
 165     {
 166         ErrorThread( p_spudec );
 167     }
 168
 169     /* End of thread */
 170     intf_WarnMsg( 1, "spudec: destroying spu decoder thread %i", getpid() );
 171     EndThread( p_spudec );
 172 }
 173
 174 /*****************************************************************************
 175  * ErrorThread: RunThread() error loop
 176  *****************************************************************************
 177  * This function is called when an error occured during thread main's loop. The
 178  * thread can still receive feed, but must be ready to terminate as soon as
 179  * possible.
 180  *****************************************************************************/
 181 static void ErrorThread( spudec_thread_t *p_spudec )
 182 {
 183     /* We take the lock, because we are going to read/write the start/end
 184      * indexes of the decoder fifo */
 185     vlc_mutex_lock( &p_spudec->p_fifo->data_lock );
 186
 187     /* Wait until a `die' order is sent */
 188     while( !p_spudec->p_fifo->b_die )
 189     {
 190         /* Trash all received PES packets */
 191         while( !DECODER_FIFO_ISEMPTY(*p_spudec->p_fifo) )
 192         {
 193             p_spudec->p_fifo->pf_delete_pes( p_spudec->p_fifo->p_packets_mgt,
 194                     DECODER_FIFO_START(*p_spudec->p_fifo) );
 195             DECODER_FIFO_INCSTART( *p_spudec->p_fifo );
 196         }
 197
 198         /* Waiting for the input thread to put new PES packets in the fifo */
 199         vlc_cond_wait( &p_spudec->p_fifo->data_wait,
 200                        &p_spudec->p_fifo->data_lock );
 201     }
 202
 203     /* We can release the lock before leaving */
 204     vlc_mutex_unlock( &p_spudec->p_fifo->data_lock );
 205 }
 206
 207 /*****************************************************************************
 208  * EndThread: thread destruction
 209  *****************************************************************************
 210  * This function is called when the thread ends after a sucessful
 211  * initialization.
 212  *****************************************************************************/
 213 static void EndThread( spudec_thread_t *p_spudec )
 214 {
 215     free( p_spudec->p_config );
 216     free( p_spudec );
 217 }
 218
 219 /*****************************************************************************
 220  * SyncPacket: get in sync with the stream
 221  *****************************************************************************
 222  * This function makes a few sanity checks and returns 0 if it looks like we
 223  * are at the beginning of a subpicture packet.
 224  *****************************************************************************/
 225 static int SyncPacket( spudec_thread_t *p_spudec )
 226 {
 227     /* Re-align the buffer on an 8-bit boundary */
 228     RealignBits( &p_spudec->bit_stream );
 229
 230     /* The total SPU packet size, often bigger than a PS packet */
 231     p_spudec->i_spu_size = GetBits( &p_spudec->bit_stream, 16 );
 232
 233     /* The RLE stuff size (remove 4 because we just read 32 bits) */
 234     p_spudec->i_rle_size = ShowBits( &p_spudec->bit_stream, 16 ) - 4;
 235
 236     /* If the values we got are a bit strange, skip packet */
 237     if( p_spudec->i_rle_size >= p_spudec->i_spu_size )
 238     {
 239         return( 1 );
 240     }
 241
 242     RemoveBits( &p_spudec->bit_stream, 16 );
 243
 244     return( 0 );
 245 }
 246
 247 /*****************************************************************************
 248  * ParsePacket: parse an SPU packet and send it to the video output
 249  *****************************************************************************
 250  * This function parses the SPU packet and, if valid, sends it to the
 251  * video output.
 252  *****************************************************************************/
 253 static void ParsePacket( spudec_thread_t *p_spudec )
 254 {
 255     subpicture_t * p_spu;
 256     u8           * p_src;
 257
 258     /* We cannot display a subpicture with no date */
 259     if( DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts == 0 )
 260     {
 261         return;
 262     }
 263
 264     /* Allocate the subpicture internal data. */
 265     p_spu = vout_CreateSubPicture( p_spudec->p_vout, DVD_SUBPICTURE,
 266                                    p_spudec->i_rle_size * 4 );
 267     /* Rationale for the "p_spudec->i_rle_size * 4": we are going to
 268      * expand the RLE stuff so that we won't need to read nibbles later
 269      * on. This will speed things up a lot. Plus, we'll only need to do
 270      * this stupid interlacing stuff once. */
 271
 272     if( p_spu == NULL )
 273     {
 274         return;
 275     }
 276
 277     /* Get display time now. If we do it later, we may miss a PTS. */
 278     p_spu->begin_date = p_spu->end_date
 279                     = DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts;
 280
 281     /* Allocate the temporary buffer we will parse */
 282     p_src = malloc( p_spudec->i_rle_size );
 283
 284     if( p_src == NULL )
 285     {
 286         intf_ErrMsg( "spudec error: could not allocate p_src" );
 287         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 288         return;
 289     }
 290
 291     /* Get RLE data */
 292     GetChunk( &p_spudec->bit_stream, p_src, p_spudec->i_rle_size );
 293
 294 #if 0
 295     /* Dump the subtitle info */
 296     intf_WarnHexDump( 0, p_spu->p_data, p_spudec->i_rle_size );
 297 #endif
 298
 299     /* Getting the control part */
 300     if( ParseControlSequences( p_spudec, p_spu ) )
 301     {
 302         /* There was a parse error, delete the subpicture */
 303         free( p_src );
 304         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 305         return;
 306     }
 307
 308     if( ParseRLE( p_src, p_spu ) )
 309     {
 310         /* There was a parse error, delete the subpicture */
 311         free( p_src );
 312         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 313         return;
 314     }
 315
 316     intf_WarnMsg( 1, "spudec: got a valid %ix%i subtitle at (%i,%i), "
 317                      "RLE offsets: 0x%x 0x%x",
 318                   p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y,
 319                   p_spu->type.spu.i_offset[0], p_spu->type.spu.i_offset[1] );
 320
 321     /* SPU is finished - we can ask the video output to display it */
 322     vout_DisplaySubPicture( p_spudec->p_vout, p_spu );
 323
 324     /* Clean up */
 325     free( p_src );
 326 }
 327
 328 /*****************************************************************************
 329  * ParseControlSequences: parse all SPU control sequences
 330  *****************************************************************************
 331  * This is the most important part in SPU decoding. We get dates, palette
 332  * information, coordinates, and so on. For more information on the
 333  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 334  *****************************************************************************/
 335 static int ParseControlSequences( spudec_thread_t *p_spudec,
 336                                   subpicture_t * p_spu )
 337 {
 338     /* Our current index in the SPU packet */
 339     int i_index = p_spudec->i_rle_size + 4;
 340
 341     /* The next start-of-control-sequence index and the previous one */
 342     int i_next_index = 0, i_prev_index;
 343
 344     /* Command time and date */
 345     u8  i_command;
 346     int i_date;
 347
 348     do
 349     {
 350         /* Get the control sequence date */
 351         i_date = GetBits( &p_spudec->bit_stream, 16 );
 352
 353         /* Next offset */
 354         i_prev_index = i_next_index;
 355         i_next_index = GetBits( &p_spudec->bit_stream, 16 );
 356
 357         /* Skip what we just read */
 358         i_index += 4;
 359
 360         do
 361         {
 362             i_command = GetBits( &p_spudec->bit_stream, 8 );
 363             i_index++;
 364
 365             switch( i_command )
 366             {
 367                 case SPU_CMD_FORCE_DISPLAY:
 368
 369                     /* 00 (force displaying) */
 370                     break;
 371
 372                 /* Convert the dates in seconds to PTS values */
 373                 case SPU_CMD_START_DISPLAY:
 374
 375                     /* 01 (start displaying) */
 376                     p_spu->begin_date += ( i_date * 11000 );
 377
 378                     break;
 379
 380                 case SPU_CMD_STOP_DISPLAY:
 381
 382                     /* 02 (stop displaying) */
 383                     p_spu->end_date += ( i_date * 11000 );
 384
 385                     break;
 386
 387                 case SPU_CMD_SET_PALETTE:
 388
 389                     /* 03xxxx (palette) - trashed */
 390                     RemoveBits( &p_spudec->bit_stream, 16 );
 391                     i_index += 2;
 392
 393                     break;
 394
 395                 case SPU_CMD_SET_ALPHACHANNEL:
 396
 397                     /* 04xxxx (alpha channel) - trashed */
 398                     RemoveBits( &p_spudec->bit_stream, 16 );
 399                     i_index += 2;
 400
 401                     break;
 402
 403                 case SPU_CMD_SET_COORDINATES:
 404
 405                     /* 05xxxyyyxxxyyy (coordinates) */
 406                     p_spu->i_x = GetBits( &p_spudec->bit_stream, 12 );
 407                     p_spu->i_width = GetBits( &p_spudec->bit_stream, 12 )
 408                                       - p_spu->i_x + 1;
 409
 410                     p_spu->i_y = GetBits( &p_spudec->bit_stream, 12 );
 411                     p_spu->i_height = GetBits( &p_spudec->bit_stream, 12 )
 412                                        - p_spu->i_y + 1;
 413
 414                     i_index += 6;
 415
 416                     break;
 417
 418                 case SPU_CMD_SET_OFFSETS:
 419
 420                     /* 06xxxxyyyy (byte offsets) */
 421                     p_spu->type.spu.i_offset[0] =
 422                         GetBits( &p_spudec->bit_stream, 16 ) - 4;
 423
 424                     p_spu->type.spu.i_offset[1] =
 425                         GetBits( &p_spudec->bit_stream, 16 ) - 4;
 426
 427                     i_index += 4;
 428
 429                     break;
 430
 431                 case SPU_CMD_END:
 432
 433                     /* ff (end) */
 434                     break;
 435
 436                 default:
 437
 438                     /* xx (unknown command) */
 439                     intf_ErrMsg( "spudec error: unknown command 0x%.2x",
 440                                  i_command );
 441                     return( 1 );
 442             }
 443
 444         } while( i_command != SPU_CMD_END );
 445
 446     } while( i_index == i_next_index );
 447
 448     /* Check that the last index matches the previous one */
 449     if( i_next_index != i_prev_index )
 450     {
 451         intf_ErrMsg( "spudec error: index mismatch (0x%.4x != 0x%.4x)",
 452                      i_next_index, i_prev_index );
 453         return( 1 );
 454     }
 455
 456     if( i_index > p_spudec->i_spu_size )
 457     {
 458         intf_ErrMsg( "spudec error: uh-oh, we went too far (0x%.4x > 0x%.4x)",
 459                      i_index, p_spudec->i_spu_size );
 460         return( 1 );
 461     }
 462
 463     /* Get rid of padding bytes */
 464     switch( p_spudec->i_spu_size - i_index )
 465     {
 466         case 1:
 467
 468             RemoveBits( &p_spudec->bit_stream, 8 );
 469             i_index++;
 470
 471         case 0:
 472
 473             /* Zero or one padding byte, quite usual */
 474
 475             break;
 476
 477         default:
 478
 479             /* More than one padding byte - this is very strange, but
 480              * we can deal with it */
 481             intf_WarnMsg( 2, "spudec warning: %i padding bytes, we usually "
 482                              "get 1 or none",
 483                           p_spudec->i_spu_size - i_index );
 484
 485             while( i_index < p_spudec->i_spu_size )
 486             {
 487                 RemoveBits( &p_spudec->bit_stream, 8 );
 488                 i_index++;
 489             }
 490
 491             break;
 492     }
 493
 494     /* Successfully parsed ! */
 495     return( 0 );
 496 }
 497
 498 /*****************************************************************************
 499  * ParseRLE: parse the RLE part of the subtitle
 500  *****************************************************************************
 501  * This part parses the subtitle graphical data and stores it in a more
 502  * convenient structure for later decoding. For more information on the
 503  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 504  *****************************************************************************/
 505 static int ParseRLE( u8 *p_src, subpicture_t * p_spu )
 506 {
 507     unsigned int i_code;
 508     unsigned int i_id = 0;
 509
 510     unsigned int i_width = p_spu->i_width;
 511     unsigned int i_height = p_spu->i_height;
 512     unsigned int i_x, i_y;
 513
 514     u16 *p_dest = (u16 *)p_spu->p_data;
 515
 516     /* The subtitles are interlaced, we need two offsets */
 517     unsigned int  pi_table[ 2 ];
 518     unsigned int *pi_offset;
 519
 520     pi_table[ 0 ] = p_spu->type.spu.i_offset[ 0 ] << 1;
 521     pi_table[ 1 ] = p_spu->type.spu.i_offset[ 1 ] << 1;
 522
 523     for( i_y = 0 ; i_y < i_height ; i_y++ )
 524     {
 525         pi_offset = pi_table + i_id;
 526
 527         for( i_x = 0 ; i_x < i_width ; i_x += i_code >> 2 )
 528         {
 529             i_code = AddNibble( 0, p_src, pi_offset );
 530
 531             if( i_code < 0x04 )
 532             {
 533                 i_code = AddNibble( i_code, p_src, pi_offset );
 534
 535                 if( i_code < 0x10 )
 536                 {
 537                     i_code = AddNibble( i_code, p_src, pi_offset );
 538
 539                     if( i_code < 0x040 )
 540                     {
 541                         i_code = AddNibble( i_code, p_src, pi_offset );
 542
 543                         if( i_code < 0x0100 )
 544                         {
 545                             /* If the 14 first bits are set to 0, then it's a
 546                              * new line. We emulate it. */
 547                             if( i_code < 0x0004 )
 548                             {
 549                                 i_code |= ( i_width - i_x ) << 2;
 550                             }
 551                             else
 552                             {
 553                                 /* We have a boo boo ! */
 554                                 intf_ErrMsg( "spudec error: unknown RLE code "
 555                                              "0x%.4x", i_code );
 556                                 return( 1 );
 557                             }
 558                         }
 559                     }
 560                 }
 561             }
 562
 563             if( ( (i_code >> 2) + i_x + i_y * i_width ) > i_height * i_width )
 564             {
 565                 intf_ErrMsg( "spudec error: out of bounds, %i at (%i,%i) is "
 566                              "out of %ix%i",
 567                              i_code >> 2, i_x, i_y, i_width, i_height);
 568                 return( 1 );
 569             }
 570
 571             /* We got a valid code, store it */
 572             *p_dest++ = i_code;
 573         }
 574
 575         /* Check that we didn't go too far */
 576         if( i_x > i_width )
 577         {
 578             intf_ErrMsg( "spudec error: i_x overflowed, %i > %i",
 579                          i_x, i_width );
 580             return( 1 );
 581         }
 582
 583         /* Byte-align the stream */
 584         if( *pi_offset & 0x1 )
 585         {
 586             (*pi_offset)++;
 587         }
 588
 589         /* Swap fields */
 590         i_id = ~i_id & 0x1;
 591     }
 592
 593     /* FIXME: we shouldn't need these padding bytes */
 594     while( i_y < i_height )
 595     {
 596         *p_dest++ = i_width << 2;
 597         i_y++;
 598     }
 599
 600     return( 0 );
 601 }
 602