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 1.34 2001/03/21 13:42:34 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 <stdlib.h>                                      /* malloc(), free() */
  30 #include <unistd.h>                                              /* getpid() */
  31
  32 #include "config.h"
  33 #include "common.h"
  34 #include "threads.h"
  35 #include "mtime.h"
  36
  37 #include "intf_msg.h"
  38
  39 #include "stream_control.h"
  40 #include "input_ext-dec.h"
  41
  42 #include "video.h"
  43 #include "video_output.h"
  44
  45 #include "spu_decoder.h"
  46
  47 /*****************************************************************************
  48  * Local prototypes
  49  *****************************************************************************/
  50 static int  InitThread  ( spudec_thread_t * );
  51 static void RunThread   ( spudec_thread_t * );
  52 static void ErrorThread ( spudec_thread_t * );
  53 static void EndThread   ( spudec_thread_t * );
  54
  55 static int  SyncPacket           ( spudec_thread_t * );
  56 static void ParsePacket          ( spudec_thread_t * );
  57 static int  ParseControlSequences( spudec_thread_t *, subpicture_t * );
  58 static int  ParseRLE             ( u8 *,              subpicture_t * );
  59
  60 /*****************************************************************************
  61  * spudec_CreateThread: create a spu decoder thread
  62  *****************************************************************************/
  63 vlc_thread_t spudec_CreateThread( vdec_config_t * p_config )
  64 {
  65     spudec_thread_t *     p_spudec;
  66
  67     /* Allocate the memory needed to store the thread's structure */
  68     p_spudec = (spudec_thread_t *)malloc( sizeof(spudec_thread_t) );
  69
  70     if ( p_spudec == NULL )
  71     {
  72         intf_ErrMsg( "spudec error: not enough memory "
  73                      "for spudec_CreateThread() to create the new thread" );
  74         return( 0 );
  75     }
  76
  77     /*
  78      * Initialize the thread properties
  79      */
  80     p_spudec->p_config = p_config;
  81     p_spudec->p_fifo = p_config->decoder_config.p_decoder_fifo;
  82
  83     /* Get the video output informations */
  84     p_spudec->p_vout = p_config->p_vout;
  85
  86     /* Spawn the spu decoder thread */
  87     if ( vlc_thread_create(&p_spudec->thread_id, "spu decoder",
  88          (vlc_thread_func_t)RunThread, (void *)p_spudec) )
  89     {
  90         intf_ErrMsg( "spudec error: can't spawn spu decoder thread" );
  91         free( p_spudec );
  92         return( 0 );
  93     }
  94
  95     return( p_spudec->thread_id );
  96 }
  97
  98 /* following functions are local */
  99
 100 /*****************************************************************************
 101  * InitThread: initialize spu decoder thread
 102  *****************************************************************************
 103  * This function is called from RunThread and performs the second step of the
 104  * initialization. It returns 0 on success. Note that the thread's flag are not
 105  * modified inside this function.
 106  *****************************************************************************/
 107 static int InitThread( spudec_thread_t *p_spudec )
 108 {
 109     p_spudec->p_config->decoder_config.pf_init_bit_stream(
 110             &p_spudec->bit_stream,
 111             p_spudec->p_config->decoder_config.p_decoder_fifo );
 112
 113     /* Mark thread as running and return */
 114     return( 0 );
 115 }
 116
 117 /*****************************************************************************
 118  * RunThread: spu decoder thread
 119  *****************************************************************************
 120  * spu decoder thread. This function only returns when the thread is
 121  * terminated.
 122  *****************************************************************************/
 123 static void RunThread( spudec_thread_t *p_spudec )
 124 {
 125     intf_WarnMsg( 1, "spudec: spu decoder thread %i spawned", getpid() );
 126
 127     /*
 128      * Initialize thread and free configuration
 129      */
 130     p_spudec->p_fifo->b_error = InitThread( p_spudec );
 131
 132     /*
 133      * Main loop - it is not executed if an error occured during
 134      * initialization
 135      */
 136     while( (!p_spudec->p_fifo->b_die) && (!p_spudec->p_fifo->b_error) )
 137     {
 138         if( !SyncPacket( p_spudec ) )
 139         {
 140             ParsePacket( p_spudec );
 141         }
 142     }
 143
 144     /*
 145      * Error loop
 146      */
 147     if( p_spudec->p_fifo->b_error )
 148     {
 149         ErrorThread( p_spudec );
 150     }
 151
 152     /* End of thread */
 153     intf_WarnMsg( 1, "spudec: destroying spu decoder thread %i", getpid() );
 154     EndThread( p_spudec );
 155 }
 156
 157 /*****************************************************************************
 158  * ErrorThread: RunThread() error loop
 159  *****************************************************************************
 160  * This function is called when an error occured during thread main's loop. The
 161  * thread can still receive feed, but must be ready to terminate as soon as
 162  * possible.
 163  *****************************************************************************/
 164 static void ErrorThread( spudec_thread_t *p_spudec )
 165 {
 166     /* We take the lock, because we are going to read/write the start/end
 167      * indexes of the decoder fifo */
 168     vlc_mutex_lock( &p_spudec->p_fifo->data_lock );
 169
 170     /* Wait until a `die' order is sent */
 171     while( !p_spudec->p_fifo->b_die )
 172     {
 173         /* Trash all received PES packets */
 174         while( !DECODER_FIFO_ISEMPTY(*p_spudec->p_fifo) )
 175         {
 176             p_spudec->p_fifo->pf_delete_pes( p_spudec->p_fifo->p_packets_mgt,
 177                     DECODER_FIFO_START(*p_spudec->p_fifo) );
 178             DECODER_FIFO_INCSTART( *p_spudec->p_fifo );
 179         }
 180
 181         /* Waiting for the input thread to put new PES packets in the fifo */
 182         vlc_cond_wait( &p_spudec->p_fifo->data_wait,
 183                        &p_spudec->p_fifo->data_lock );
 184     }
 185
 186     /* We can release the lock before leaving */
 187     vlc_mutex_unlock( &p_spudec->p_fifo->data_lock );
 188 }
 189
 190 /*****************************************************************************
 191  * EndThread: thread destruction
 192  *****************************************************************************
 193  * This function is called when the thread ends after a sucessful
 194  * initialization.
 195  *****************************************************************************/
 196 static void EndThread( spudec_thread_t *p_spudec )
 197 {
 198     free( p_spudec->p_config );
 199     free( p_spudec );
 200 }
 201
 202 /*****************************************************************************
 203  * SyncPacket: get in sync with the stream
 204  *****************************************************************************
 205  * This function makes a few sanity checks and returns 0 if it looks like we
 206  * are at the beginning of a subpicture packet.
 207  *****************************************************************************/
 208 static int SyncPacket( spudec_thread_t *p_spudec )
 209 {
 210     /* Re-align the buffer on an 8-bit boundary */
 211     RealignBits( &p_spudec->bit_stream );
 212
 213     /* The total SPU packet size, often bigger than a PS packet */
 214     p_spudec->i_spu_size = GetBits( &p_spudec->bit_stream, 16 );
 215
 216     /* The RLE stuff size (remove 4 because we just read 32 bits) */
 217     p_spudec->i_rle_size = ShowBits( &p_spudec->bit_stream, 16 ) - 4;
 218
 219     /* If the values we got are a bit strange, skip packet */
 220     if( p_spudec->i_rle_size >= p_spudec->i_spu_size )
 221     {
 222         return( 1 );
 223     }
 224
 225     RemoveBits( &p_spudec->bit_stream, 16 );
 226
 227     return( 0 );
 228 }
 229
 230 /*****************************************************************************
 231  * ParsePacket: parse an SPU packet and send it to the video output
 232  *****************************************************************************
 233  * This function parses the SPU packet and, if valid, sends it to the
 234  * video output.
 235  *****************************************************************************/
 236 static void ParsePacket( spudec_thread_t *p_spudec )
 237 {
 238     subpicture_t * p_spu;
 239     u8           * p_src;
 240
 241     /* We cannot display a subpicture with no date */
 242     if( DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts == 0 )
 243     {
 244         return;
 245     }
 246
 247     /* Allocate the subpicture internal data. */
 248     p_spu = vout_CreateSubPicture( p_spudec->p_vout, DVD_SUBPICTURE,
 249                                    p_spudec->i_rle_size * 4 );
 250     /* Rationale for the "p_spudec->i_rle_size * 4": we are going to
 251      * expand the RLE stuff so that we won't need to read nibbles later
 252      * on. This will speed things up a lot. Plus, we'll only need to do
 253      * this stupid interlacing stuff once. */
 254
 255     if( p_spu == NULL )
 256     {
 257         return;
 258     }
 259
 260     /* Get display time now. If we do it later, we may miss a PTS. */
 261     p_spu->begin_date = p_spu->end_date
 262                     = DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts;
 263
 264     /* Allocate the temporary buffer we will parse */
 265     p_src = malloc( p_spudec->i_rle_size );
 266
 267     if( p_src == NULL )
 268     {
 269         intf_ErrMsg( "spudec error: could not allocate p_src" );
 270         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 271         return;
 272     }
 273
 274     /* Get RLE data */
 275     GetChunk( &p_spudec->bit_stream, p_src, p_spudec->i_rle_size );
 276
 277 #if 0
 278     /* Dump the subtitle info */
 279     intf_WarnHexDump( 0, p_spu->p_data, p_spudec->i_rle_size );
 280 #endif
 281
 282     /* Getting the control part */
 283     if( ParseControlSequences( p_spudec, p_spu ) )
 284     {
 285         /* There was a parse error, delete the subpicture */
 286         free( p_src );
 287         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 288         return;
 289     }
 290
 291     if( ParseRLE( p_src, p_spu ) )
 292     {
 293         /* There was a parse error, delete the subpicture */
 294         free( p_src );
 295         vout_DestroySubPicture( p_spudec->p_vout, p_spu );
 296         return;
 297     }
 298
 299     intf_WarnMsg( 1, "spudec: got a valid %ix%i subtitle at (%i,%i), "
 300                      "RLE offsets: 0x%x 0x%x",
 301                   p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y,
 302                   p_spu->type.spu.i_offset[0], p_spu->type.spu.i_offset[1] );
 303
 304     /* SPU is finished - we can tell the video output to display it */
 305     vout_DisplaySubPicture( p_spudec->p_vout, p_spu );
 306
 307     /* Clean up */
 308     free( p_src );
 309 }
 310
 311 /*****************************************************************************
 312  * ParseControlSequences: parse all SPU control sequences
 313  *****************************************************************************
 314  * This is the most important part in SPU decoding. We get dates, palette
 315  * information, coordinates, and so on. For more information on the
 316  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 317  *****************************************************************************/
 318 static int ParseControlSequences( spudec_thread_t *p_spudec,
 319                                   subpicture_t * p_spu )
 320 {
 321     /* Our current index in the SPU packet */
 322     int i_index = p_spudec->i_rle_size + 4;
 323
 324     /* The next start-of-control-sequence index and the previous one */
 325     int i_next_index = 0, i_prev_index;
 326
 327     /* Command time and date */
 328     u8  i_command;
 329     int i_date;
 330
 331     do
 332     {
 333         /* Get the control sequence date */
 334         i_date = GetBits( &p_spudec->bit_stream, 16 );
 335
 336         /* Next offset */
 337         i_prev_index = i_next_index;
 338         i_next_index = GetBits( &p_spudec->bit_stream, 16 );
 339
 340         /* Skip what we just read */
 341         i_index += 4;
 342
 343         do
 344         {
 345             i_command = GetBits( &p_spudec->bit_stream, 8 );
 346             i_index++;
 347
 348             switch( i_command )
 349             {
 350                 case SPU_CMD_FORCE_DISPLAY:
 351
 352                     /* 00 (force displaying) */
 353
 354                     break;
 355
 356                 /* FIXME: here we have to calculate dates. It's around
 357                  * i_date * 12000 but I don't know how much exactly. */
 358                 case SPU_CMD_START_DISPLAY:
 359
 360                     /* 01 (start displaying) */
 361                     p_spu->begin_date += ( i_date * 11000 );
 362
 363                     break;
 364
 365                 case SPU_CMD_STOP_DISPLAY:
 366
 367                     /* 02 (stop displaying) */
 368                     p_spu->end_date += ( i_date * 11000 );
 369
 370                     break;
 371
 372                 case SPU_CMD_SET_PALETTE:
 373
 374                     /* 03xxxx (palette) - trashed */
 375                     RemoveBits( &p_spudec->bit_stream, 16 );
 376                     i_index += 2;
 377
 378                     break;
 379
 380                 case SPU_CMD_SET_ALPHACHANNEL:
 381
 382                     /* 04xxxx (alpha channel) - trashed */
 383                     RemoveBits( &p_spudec->bit_stream, 16 );
 384                     i_index += 2;
 385
 386                     break;
 387
 388                 case SPU_CMD_SET_COORDINATES:
 389
 390                     /* 05xxxyyyxxxyyy (coordinates) */
 391                     p_spu->i_x = GetBits( &p_spudec->bit_stream, 12 );
 392                     p_spu->i_width = GetBits( &p_spudec->bit_stream, 12 )
 393                                       - p_spu->i_x + 1;
 394
 395                     p_spu->i_y = GetBits( &p_spudec->bit_stream, 12 );
 396                     p_spu->i_height = GetBits( &p_spudec->bit_stream, 12 )
 397                                        - p_spu->i_y + 1;
 398
 399                     i_index += 6;
 400
 401                     break;
 402
 403                 case SPU_CMD_SET_OFFSETS:
 404
 405                     /* 06xxxxyyyy (byte offsets) */
 406                     p_spu->type.spu.i_offset[0] =
 407                         GetBits( &p_spudec->bit_stream, 16 ) - 4;
 408
 409                     p_spu->type.spu.i_offset[1] =
 410                         GetBits( &p_spudec->bit_stream, 16 ) - 4;
 411
 412                     i_index += 4;
 413
 414                     break;
 415
 416                 case SPU_CMD_END:
 417
 418                     /* ff (end) */
 419
 420                     break;
 421
 422                 default:
 423
 424                     /* ?? (unknown command) */
 425                     intf_ErrMsg( "spudec error: unknown command 0x%.2x",
 426                                  i_command );
 427                     return( 1 );
 428             }
 429
 430         } while( i_command != SPU_CMD_END );
 431
 432     } while( i_index == i_next_index );
 433
 434     /* Check that the last index matches the previous one */
 435     if( i_next_index != i_prev_index )
 436     {
 437         intf_ErrMsg( "spudec error: index mismatch (0x%.4x != 0x%.4x)",
 438                      i_next_index, i_prev_index );
 439         return( 1 );
 440     }
 441
 442     if( i_index > p_spudec->i_spu_size )
 443     {
 444         intf_ErrMsg( "spudec error: uh-oh, we went too far (0x%.4x > 0x%.4x)",
 445                      i_index, p_spudec->i_spu_size );
 446         return( 1 );
 447     }
 448
 449     /* Get rid of padding bytes */
 450     switch( p_spudec->i_spu_size - i_index )
 451     {
 452         case 1:
 453
 454             RemoveBits( &p_spudec->bit_stream, 8 );
 455             i_index++;
 456
 457         case 0:
 458
 459             /* Zero or one padding byte, quite usual */
 460
 461             break;
 462
 463         default:
 464
 465             /* More than one padding byte - this is very strange, but
 466              * we can deal with it */
 467             intf_WarnMsg( 2, "spudec warning: %i padding bytes",
 468                           p_spudec->i_spu_size - i_index );
 469
 470             while( i_index < p_spudec->i_spu_size )
 471             {
 472                 RemoveBits( &p_spudec->bit_stream, 8 );
 473                 i_index++;
 474             }
 475
 476             break;
 477     }
 478
 479     /* Successfully parsed ! */
 480     return( 0 );
 481 }
 482
 483 /*****************************************************************************
 484  * ParseRLE: parse the RLE part of the subtitle
 485  *****************************************************************************
 486  * This part parses the subtitle graphical data and stores it in a more
 487  * convenient structure for later decoding. For more information on the
 488  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 489  *****************************************************************************/
 490 static int ParseRLE( u8 *p_src, subpicture_t * p_spu )
 491 {
 492     unsigned int i_code;
 493     unsigned int i_id = 0;
 494
 495     unsigned int i_width = p_spu->i_width;
 496     unsigned int i_height = p_spu->i_height;
 497     unsigned int i_x, i_y;
 498
 499     u16 *p_dest = (u16 *)p_spu->p_data;
 500
 501     /* The subtitles are interlaced, we need two offsets */
 502     unsigned int  pi_table[2];
 503     unsigned int *pi_offset;
 504     pi_table[0] = p_spu->type.spu.i_offset[0] << 1;
 505     pi_table[1] = p_spu->type.spu.i_offset[1] << 1;
 506
 507     for( i_y = 0 ; i_y < i_height ; i_y++ )
 508     {
 509         pi_offset = pi_table + i_id;
 510
 511         for( i_x = 0 ; i_x < i_width ; i_x += i_code >> 2 )
 512         {
 513             i_code = AddNibble( 0, p_src, pi_offset );
 514
 515             if( i_code < 0x04 )
 516             {
 517                 i_code = AddNibble( i_code, p_src, pi_offset );
 518
 519                 if( i_code < 0x10 )
 520                 {
 521                     i_code = AddNibble( i_code, p_src, pi_offset );
 522
 523                     if( i_code < 0x040 )
 524                     {
 525                         i_code = AddNibble( i_code, p_src, pi_offset );
 526
 527                         if( i_code < 0x0100 )
 528                         {
 529                             /* If the 14 first bits are set to 0, then it's a
 530                              * new line. We emulate it. */
 531                             if( i_code < 0x0004 )
 532                             {
 533                                 i_code |= ( i_width - i_x ) << 2;
 534                             }
 535                             else
 536                             {
 537                                 /* We have a boo boo ! */
 538                                 intf_ErrMsg( "spudec error: unknown code %.4x",
 539                                              i_code );
 540                                 return( 1 );
 541                             }
 542                         }
 543                     }
 544                 }
 545             }
 546
 547             if( ( (i_code >> 2) + i_x + i_y * i_width ) > i_height * i_width )
 548             {
 549                 intf_ErrMsg( "spudec error: out of bounds, %i at (%i,%i) is "
 550                              "out of %ix%i",
 551                              i_code >> 2, i_x, i_y, i_width, i_height);
 552                 return( 1 );
 553             }
 554
 555             /* We got a valid code, store it */
 556             *p_dest++ = i_code;
 557         }
 558
 559         /* Check that we didn't go too far */
 560         if( i_x > i_width )
 561         {
 562             intf_ErrMsg( "spudec error: i_x overflowed, %i > %i",
 563                          i_x, i_width );
 564             return( 1 );
 565         }
 566
 567         /* Byte-align the stream */
 568         if( *pi_offset & 0x1 )
 569         {
 570             (*pi_offset)++;
 571         }
 572
 573         /* Swap fields */
 574         i_id = ~i_id & 0x1;
 575     }
 576
 577     /* FIXME: we shouldn't need these padding bytes */
 578     while( i_y < i_height )
 579     {
 580         *p_dest++ = i_width << 2;
 581         i_y++;
 582     }
 583
 584     return( 0 );
 585 }
 586