git.sesse.net Git - vlc/blob - modules/codec/spudec/parse.c

   1 /*****************************************************************************
   2  * parse.c: SPU parser
   3  *****************************************************************************
   4  * Copyright (C) 2000-2001, 2005, 2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Sam Hocevar <sam@zoy.org>
   8  *          Laurent Aimar <fenrir@via.ecp.fr>
   9  *          Gildas Bazin <gbazin@videolan.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 /*****************************************************************************
  27  * Preamble
  28  *****************************************************************************/
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc_common.h>
  34 #include <vlc_vout.h>
  35 #include <vlc_codec.h>
  36 #include <vlc_input.h>
  37
  38 #include "spudec.h"
  39
  40 /*****************************************************************************
  41  * Local prototypes.
  42  *****************************************************************************/
  43 typedef struct
  44 {
  45     int i_width;
  46     int i_height;
  47     int i_x;
  48     int i_y;
  49 } spu_properties_t;
  50
  51 static int  ParseControlSeq( decoder_t *, subpicture_t *, subpicture_data_t *,
  52                              spu_properties_t * );
  53 static int  ParseRLE       ( decoder_t *, subpicture_data_t *,
  54                              const spu_properties_t * );
  55 static void Render         ( decoder_t *, subpicture_t *, subpicture_data_t *,
  56                              const spu_properties_t * );
  57
  58 /*****************************************************************************
  59  * AddNibble: read a nibble from a source packet and add it to our integer.
  60  *****************************************************************************/
  61 static inline unsigned int AddNibble( unsigned int i_code,
  62                                       uint8_t *p_src, unsigned int *pi_index )
  63 {
  64     if( *pi_index & 0x1 )
  65     {
  66         return( i_code << 4 | ( p_src[(*pi_index)++ >> 1] & 0xf ) );
  67     }
  68     else
  69     {
  70         return( i_code << 4 | p_src[(*pi_index)++ >> 1] >> 4 );
  71     }
  72 }
  73
  74 /*****************************************************************************
  75  * ParsePacket: parse an SPU packet and send it to the video output
  76  *****************************************************************************
  77  * This function parses the SPU packet and, if valid, sends it to the
  78  * video output.
  79  *****************************************************************************/
  80 subpicture_t * ParsePacket( decoder_t *p_dec )
  81 {
  82     decoder_sys_t *p_sys = p_dec->p_sys;
  83     subpicture_data_t *p_spu_data;
  84     subpicture_t *p_spu;
  85     spu_properties_t spu_properties;
  86
  87     /* Allocate the subpicture internal data. */
  88     p_spu = p_dec->pf_spu_buffer_new( p_dec );
  89     if( !p_spu ) return NULL;
  90
  91     /* Rationale for the "p_spudec->i_rle_size * 4": we are going to
  92      * expand the RLE stuff so that we won't need to read nibbles later
  93      * on. This will speed things up a lot. Plus, we'll only need to do
  94      * this stupid interlacing stuff once. */
  95     p_spu_data = malloc( sizeof(subpicture_data_t) + 4 * p_sys->i_rle_size );
  96     p_spu_data->p_data = (uint8_t *)p_spu_data + sizeof(subpicture_data_t);
  97     p_spu_data->b_palette = false;
  98     p_spu_data->b_auto_crop = false;
  99     p_spu_data->i_y_top_offset = 0;
 100     p_spu_data->i_y_bottom_offset = 0;
 101
 102     p_spu_data->pi_alpha[0] = 0x00;
 103     p_spu_data->pi_alpha[1] = 0x0f;
 104     p_spu_data->pi_alpha[2] = 0x0f;
 105     p_spu_data->pi_alpha[3] = 0x0f;
 106
 107     /* Get display time now. If we do it later, we may miss the PTS. */
 108     p_spu_data->i_pts = p_sys->i_pts;
 109
 110     p_spu->i_original_picture_width =
 111         p_dec->fmt_in.subs.spu.i_original_frame_width;
 112     p_spu->i_original_picture_height =
 113         p_dec->fmt_in.subs.spu.i_original_frame_height;
 114
 115     memset( &spu_properties, 0, sizeof(spu_properties) );
 116
 117     /* Getting the control part */
 118     if( ParseControlSeq( p_dec, p_spu, p_spu_data, &spu_properties ) )
 119     {
 120         /* There was a parse error, delete the subpicture */
 121         p_dec->pf_spu_buffer_del( p_dec, p_spu );
 122         return NULL;
 123     }
 124
 125     /* We try to display it */
 126     if( ParseRLE( p_dec, p_spu_data, &spu_properties ) )
 127     {
 128         /* There was a parse error, delete the subpicture */
 129         p_dec->pf_spu_buffer_del( p_dec, p_spu );
 130         return NULL;
 131     }
 132
 133 #ifdef DEBUG_SPUDEC
 134     msg_Dbg( p_dec, "total size: 0x%x, RLE offsets: 0x%x 0x%x",
 135              p_sys->i_spu_size,
 136              p_spu_data->pi_offset[0], p_spu_data->pi_offset[1] );
 137 #endif
 138
 139     Render( p_dec, p_spu, p_spu_data, &spu_properties );
 140     free( p_spu_data );
 141
 142     return p_spu;
 143 }
 144
 145 /*****************************************************************************
 146  * ParseControlSeq: parse all SPU control sequences
 147  *****************************************************************************
 148  * This is the most important part in SPU decoding. We get dates, palette
 149  * information, coordinates, and so on. For more information on the
 150  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 151  *****************************************************************************/
 152 static int ParseControlSeq( decoder_t *p_dec, subpicture_t *p_spu,
 153                             subpicture_data_t *p_spu_data, spu_properties_t *p_spu_properties )
 154 {
 155     decoder_sys_t *p_sys = p_dec->p_sys;
 156
 157     /* Our current index in the SPU packet */
 158     unsigned int i_index = p_sys->i_rle_size + 4;
 159
 160     /* The next start-of-control-sequence index and the previous one */
 161     unsigned int i_next_seq = 0, i_cur_seq = 0;
 162
 163     /* Command and date */
 164     uint8_t i_command = SPU_CMD_END;
 165     mtime_t date = 0;
 166
 167     if( !p_spu || !p_spu_data )
 168         return VLC_EGENERIC;
 169
 170     /* Initialize the structure */
 171     p_spu->i_start = p_spu->i_stop = 0;
 172     p_spu->b_ephemer = false;
 173
 174     for( i_index = 4 + p_sys->i_rle_size; i_index < p_sys->i_spu_size ; )
 175     {
 176         /* If we just read a command sequence, read the next one;
 177          * otherwise, go on with the commands of the current sequence. */
 178         if( i_command == SPU_CMD_END )
 179         {
 180             if( i_index + 4 > p_sys->i_spu_size )
 181             {
 182                 msg_Err( p_dec, "overflow in SPU command sequence" );
 183                 return VLC_EGENERIC;
 184             }
 185
 186             /* Get the control sequence date */
 187             date = (mtime_t)GetWBE( &p_sys->buffer[i_index] ) * 11000;
 188             if( p_sys->i_rate )
 189                 date = date * p_sys->i_rate / INPUT_RATE_DEFAULT;
 190
 191             /* Next offset */
 192             i_cur_seq = i_index;
 193             i_next_seq = GetWBE( &p_sys->buffer[i_index+2] );
 194
 195             if( i_next_seq > p_sys->i_spu_size )
 196             {
 197                 msg_Err( p_dec, "overflow in SPU next command sequence" );
 198                 return VLC_EGENERIC;
 199             }
 200
 201             /* Skip what we just read */
 202             i_index += 4;
 203         }
 204
 205         i_command = p_sys->buffer[i_index];
 206
 207         switch( i_command )
 208         {
 209         case SPU_CMD_FORCE_DISPLAY: /* 00 (force displaying) */
 210             p_spu->i_start = p_spu_data->i_pts + date;
 211             p_spu->b_ephemer = true;
 212             i_index += 1;
 213             break;
 214
 215         /* Convert the dates in seconds to PTS values */
 216         case SPU_CMD_START_DISPLAY: /* 01 (start displaying) */
 217             p_spu->i_start = p_spu_data->i_pts + date;
 218             i_index += 1;
 219             break;
 220
 221         case SPU_CMD_STOP_DISPLAY: /* 02 (stop displaying) */
 222             p_spu->i_stop = p_spu_data->i_pts + date;
 223             i_index += 1;
 224             break;
 225
 226         case SPU_CMD_SET_PALETTE:
 227             /* 03xxxx (palette) */
 228             if( i_index + 3 > p_sys->i_spu_size )
 229             {
 230                 msg_Err( p_dec, "overflow in SPU command" );
 231                 return VLC_EGENERIC;
 232             }
 233
 234             if( p_dec->fmt_in.subs.spu.palette[0] == 0xBeeF )
 235             {
 236                 unsigned int idx[4];
 237                 int i;
 238
 239                 p_spu_data->b_palette = true;
 240
 241                 idx[0] = (p_sys->buffer[i_index+1]>>4)&0x0f;
 242                 idx[1] = (p_sys->buffer[i_index+1])&0x0f;
 243                 idx[2] = (p_sys->buffer[i_index+2]>>4)&0x0f;
 244                 idx[3] = (p_sys->buffer[i_index+2])&0x0f;
 245
 246                 for( i = 0; i < 4 ; i++ )
 247                 {
 248                     uint32_t i_color = p_dec->fmt_in.subs.spu.palette[1+idx[i]];
 249
 250                     /* FIXME: this job should be done sooner */
 251                     p_spu_data->pi_yuv[3-i][0] = (i_color>>16) & 0xff;
 252                     p_spu_data->pi_yuv[3-i][1] = (i_color>>0) & 0xff;
 253                     p_spu_data->pi_yuv[3-i][2] = (i_color>>8) & 0xff;
 254                 }
 255             }
 256
 257             i_index += 3;
 258             break;
 259
 260         case SPU_CMD_SET_ALPHACHANNEL: /* 04xxxx (alpha channel) */
 261             if( i_index + 3 > p_sys->i_spu_size )
 262             {
 263                 msg_Err( p_dec, "overflow in SPU command" );
 264                 return VLC_EGENERIC;
 265             }
 266
 267             p_spu_data->pi_alpha[3] = (p_sys->buffer[i_index+1]>>4)&0x0f;
 268             p_spu_data->pi_alpha[2] = (p_sys->buffer[i_index+1])&0x0f;
 269             p_spu_data->pi_alpha[1] = (p_sys->buffer[i_index+2]>>4)&0x0f;
 270             p_spu_data->pi_alpha[0] = (p_sys->buffer[i_index+2])&0x0f;
 271
 272             i_index += 3;
 273             break;
 274
 275         case SPU_CMD_SET_COORDINATES: /* 05xxxyyyxxxyyy (coordinates) */
 276             if( i_index + 7 > p_sys->i_spu_size )
 277             {
 278                 msg_Err( p_dec, "overflow in SPU command" );
 279                 return VLC_EGENERIC;
 280             }
 281
 282             p_spu_properties->i_x = (p_sys->buffer[i_index+1]<<4)|
 283                          ((p_sys->buffer[i_index+2]>>4)&0x0f);
 284             p_spu_properties->i_width = (((p_sys->buffer[i_index+2]&0x0f)<<8)|
 285                               p_sys->buffer[i_index+3]) - p_spu_properties->i_x + 1;
 286
 287             p_spu_properties->i_y = (p_sys->buffer[i_index+4]<<4)|
 288                          ((p_sys->buffer[i_index+5]>>4)&0x0f);
 289             p_spu_properties->i_height = (((p_sys->buffer[i_index+5]&0x0f)<<8)|
 290                               p_sys->buffer[i_index+6]) - p_spu_properties->i_y + 1;
 291
 292             /* Auto crop fullscreen subtitles */
 293             if( p_spu_properties->i_height > 250 )
 294                 p_spu_data->b_auto_crop = true;
 295
 296             i_index += 7;
 297             break;
 298
 299         case SPU_CMD_SET_OFFSETS: /* 06xxxxyyyy (byte offsets) */
 300             if( i_index + 5 > p_sys->i_spu_size )
 301             {
 302                 msg_Err( p_dec, "overflow in SPU command" );
 303                 return VLC_EGENERIC;
 304             }
 305
 306             p_spu_data->pi_offset[0] = GetWBE(&p_sys->buffer[i_index+1]) - 4;
 307             p_spu_data->pi_offset[1] = GetWBE(&p_sys->buffer[i_index+3]) - 4;
 308             i_index += 5;
 309             break;
 310
 311         case SPU_CMD_END: /* ff (end) */
 312             i_index += 1;
 313             break;
 314
 315         default: /* xx (unknown command) */
 316             msg_Warn( p_dec, "unknown SPU command 0x%.2x", i_command );
 317             if( i_index + 1 < i_next_seq )
 318             {
 319                  /* There is at least one other command sequence */
 320                  if( p_sys->buffer[i_next_seq - 1] == SPU_CMD_END )
 321                  {
 322                      /* This is consistent. Skip to that command sequence. */
 323                      i_index = i_next_seq;
 324                  }
 325                  else
 326                  {
 327                      /* There were other commands. */
 328                      msg_Warn( p_dec, "cannot recover, dropping subtitle" );
 329                      return VLC_EGENERIC;
 330                  }
 331             }
 332             else
 333             {
 334                 /* We were in the last command sequence. Stop parsing by
 335                  * pretending we met an SPU_CMD_END command. */
 336                 i_command = SPU_CMD_END;
 337                 i_index++;
 338             }
 339         }
 340
 341         /* We need to check for quit commands here */
 342         if( !vlc_object_alive (p_dec) )
 343         {
 344             return VLC_EGENERIC;
 345         }
 346
 347         if( i_command == SPU_CMD_END && i_index != i_next_seq )
 348         {
 349             break;
 350         }
 351     }
 352
 353     /* Check that the next sequence index matches the current one */
 354     if( i_next_seq != i_cur_seq )
 355     {
 356         msg_Err( p_dec, "index mismatch (0x%.4x != 0x%.4x)",
 357                  i_next_seq, i_cur_seq );
 358         return VLC_EGENERIC;
 359     }
 360
 361     if( i_index > p_sys->i_spu_size )
 362     {
 363         msg_Err( p_dec, "uh-oh, we went too far (0x%.4x > 0x%.4x)",
 364                  i_index, p_sys->i_spu_size );
 365         return VLC_EGENERIC;
 366     }
 367
 368     if( !p_spu->i_start )
 369     {
 370         msg_Err( p_dec, "no `start display' command" );
 371         return VLC_EGENERIC;
 372     }
 373
 374     if( p_spu->i_stop <= p_spu->i_start && !p_spu->b_ephemer )
 375     {
 376         /* This subtitle will live for 5 seconds or until the next subtitle */
 377         p_spu->i_stop = p_spu->i_start + (mtime_t)500 * 11000;
 378         p_spu->b_ephemer = true;
 379     }
 380
 381     /* Get rid of padding bytes */
 382     if( p_sys->i_spu_size > i_index + 1 )
 383     {
 384         /* Zero or one padding byte are quite usual
 385          * More than one padding byte - this is very strange, but
 386          * we can ignore them. */
 387         msg_Warn( p_dec, "%i padding bytes, we usually get 0 or 1 of them",
 388                   p_sys->i_spu_size - i_index );
 389     }
 390
 391     /* Successfully parsed ! */
 392     return VLC_SUCCESS;
 393 }
 394
 395 /*****************************************************************************
 396  * ParseRLE: parse the RLE part of the subtitle
 397  *****************************************************************************
 398  * This part parses the subtitle graphical data and stores it in a more
 399  * convenient structure for later decoding. For more information on the
 400  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 401  *****************************************************************************/
 402 static int ParseRLE( decoder_t *p_dec,
 403                      subpicture_data_t *p_spu_data,
 404                      const spu_properties_t *p_spu_properties )
 405 {
 406     decoder_sys_t *p_sys = p_dec->p_sys;
 407     uint8_t       *p_src = &p_sys->buffer[4];
 408
 409     unsigned int i_code;
 410
 411     unsigned int i_width = p_spu_properties->i_width;
 412     unsigned int i_height = p_spu_properties->i_height;
 413     unsigned int i_x, i_y;
 414
 415     uint16_t *p_dest = (uint16_t *)p_spu_data->p_data;
 416
 417     /* The subtitles are interlaced, we need two offsets */
 418     unsigned int  i_id = 0;                   /* Start on the even SPU layer */
 419     unsigned int  pi_table[ 2 ];
 420     unsigned int *pi_offset;
 421
 422     /* Cropping */
 423     bool b_empty_top = true;
 424     unsigned int i_skipped_top = 0, i_skipped_bottom = 0;
 425     unsigned int i_transparent_code = 0;
 426
 427     /* Colormap statistics */
 428     int i_border = -1;
 429     int stats[4]; stats[0] = stats[1] = stats[2] = stats[3] = 0;
 430
 431     pi_table[ 0 ] = p_spu_data->pi_offset[ 0 ] << 1;
 432     pi_table[ 1 ] = p_spu_data->pi_offset[ 1 ] << 1;
 433
 434     for( i_y = 0 ; i_y < i_height ; i_y++ )
 435     {
 436         pi_offset = pi_table + i_id;
 437
 438         for( i_x = 0 ; i_x < i_width ; i_x += i_code >> 2 )
 439         {
 440             i_code = AddNibble( 0, p_src, pi_offset );
 441
 442             if( i_code < 0x04 )
 443             {
 444                 i_code = AddNibble( i_code, p_src, pi_offset );
 445
 446                 if( i_code < 0x10 )
 447                 {
 448                     i_code = AddNibble( i_code, p_src, pi_offset );
 449
 450                     if( i_code < 0x040 )
 451                     {
 452                         i_code = AddNibble( i_code, p_src, pi_offset );
 453
 454                         if( i_code < 0x0100 )
 455                         {
 456                             /* If the 14 first bits are set to 0, then it's a
 457                              * new line. We emulate it. */
 458                             if( i_code < 0x0004 )
 459                             {
 460                                 i_code |= ( i_width - i_x ) << 2;
 461                             }
 462                             else
 463                             {
 464                                 /* We have a boo boo ! */
 465                                 msg_Err( p_dec, "unknown RLE code "
 466                                          "0x%.4x", i_code );
 467                                 return VLC_EGENERIC;
 468                             }
 469                         }
 470                     }
 471                 }
 472             }
 473
 474             if( ( (i_code >> 2) + i_x + i_y * i_width ) > i_height * i_width )
 475             {
 476                 msg_Err( p_dec, "out of bounds, %i at (%i,%i) is out of %ix%i",
 477                          i_code >> 2, i_x, i_y, i_width, i_height );
 478                 return VLC_EGENERIC;
 479             }
 480
 481             /* Try to find the border color */
 482             if( p_spu_data->pi_alpha[ i_code & 0x3 ] != 0x00 )
 483             {
 484                 i_border = i_code & 0x3;
 485                 stats[i_border] += i_code >> 2;
 486             }
 487
 488             /* Auto crop subtitles (a lot more optimized) */
 489             if( p_spu_data->b_auto_crop )
 490             {
 491                 if( !i_y )
 492                 {
 493                     /* We assume that if the first line is transparent, then
 494                      * it is using the palette index for the
 495                      * (background) transparent color */
 496                     if( (i_code >> 2) == i_width &&
 497                         p_spu_data->pi_alpha[ i_code & 0x3 ] == 0x00 )
 498                     {
 499                         i_transparent_code = i_code;
 500                     }
 501                     else
 502                     {
 503                         p_spu_data->b_auto_crop = false;
 504                     }
 505                 }
 506
 507                 if( i_code == i_transparent_code )
 508                 {
 509                     if( b_empty_top )
 510                     {
 511                         /* This is a blank top line, we skip it */
 512                       i_skipped_top++;
 513                     }
 514                     else
 515                     {
 516                         /* We can't be sure the current lines will be skipped,
 517                          * so we store the code just in case. */
 518                       *p_dest++ = i_code;
 519                       i_skipped_bottom++;
 520                     }
 521                 }
 522                 else
 523                 {
 524                     /* We got a valid code, store it */
 525                     *p_dest++ = i_code;
 526
 527                     /* Valid code means no blank line */
 528                     b_empty_top = false;
 529                     i_skipped_bottom = 0;
 530                 }
 531             }
 532             else
 533             {
 534                 *p_dest++ = i_code;
 535             }
 536         }
 537
 538         /* Check that we didn't go too far */
 539         if( i_x > i_width )
 540         {
 541             msg_Err( p_dec, "i_x overflowed, %i > %i", i_x, i_width );
 542             return VLC_EGENERIC;
 543         }
 544
 545         /* Byte-align the stream */
 546         if( *pi_offset & 0x1 )
 547         {
 548             (*pi_offset)++;
 549         }
 550
 551         /* Swap fields */
 552         i_id = ~i_id & 0x1;
 553     }
 554
 555     /* We shouldn't get any padding bytes */
 556     if( i_y < i_height )
 557     {
 558         msg_Err( p_dec, "padding bytes found in RLE sequence" );
 559         msg_Err( p_dec, "send mail to <sam@zoy.org> if you "
 560                         "want to help debugging this" );
 561
 562         /* Skip them just in case */
 563         while( i_y < i_height )
 564         {
 565             *p_dest++ = i_width << 2;
 566             i_y++;
 567         }
 568
 569         return VLC_EGENERIC;
 570     }
 571
 572 #ifdef DEBUG_SPUDEC
 573     msg_Dbg( p_dec, "valid subtitle, size: %ix%i, position: %i,%i",
 574              p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y );
 575 #endif
 576
 577     /* Crop if necessary */
 578     if( i_skipped_top || i_skipped_bottom )
 579     {
 580 #ifdef DEBUG_SPUDEC
 581         int i_y = p_spu->i_y + i_skipped_top;
 582         int i_height = p_spu->i_height - (i_skipped_top + i_skipped_bottom);
 583 #endif
 584         p_spu_data->i_y_top_offset = i_skipped_top;
 585         p_spu_data->i_y_bottom_offset = i_skipped_bottom;
 586 #ifdef DEBUG_SPUDEC
 587         msg_Dbg( p_dec, "cropped to: %ix%i, position: %i,%i",
 588                  p_spu->i_width, i_height, p_spu->i_x, i_y );
 589 #endif
 590     }
 591
 592     /* Handle color if no palette was found */
 593     if( !p_spu_data->b_palette )
 594     {
 595         int i, i_inner = -1, i_shade = -1;
 596
 597         /* Set the border color */
 598         p_spu_data->pi_yuv[i_border][0] = 0x00;
 599         p_spu_data->pi_yuv[i_border][1] = 0x80;
 600         p_spu_data->pi_yuv[i_border][2] = 0x80;
 601         stats[i_border] = 0;
 602
 603         /* Find the inner colors */
 604         for( i = 0 ; i < 4 && i_inner == -1 ; i++ )
 605         {
 606             if( stats[i] )
 607             {
 608                 i_inner = i;
 609             }
 610         }
 611
 612         for(       ; i < 4 && i_shade == -1 ; i++ )
 613         {
 614             if( stats[i] )
 615             {
 616                 if( stats[i] > stats[i_inner] )
 617                 {
 618                     i_shade = i_inner;
 619                     i_inner = i;
 620                 }
 621                 else
 622                 {
 623                     i_shade = i;
 624                 }
 625             }
 626         }
 627
 628         /* Set the inner color */
 629         if( i_inner != -1 )
 630         {
 631             p_spu_data->pi_yuv[i_inner][0] = 0xff;
 632             p_spu_data->pi_yuv[i_inner][1] = 0x80;
 633             p_spu_data->pi_yuv[i_inner][2] = 0x80;
 634         }
 635
 636         /* Set the anti-aliasing color */
 637         if( i_shade != -1 )
 638         {
 639             p_spu_data->pi_yuv[i_shade][0] = 0x80;
 640             p_spu_data->pi_yuv[i_shade][1] = 0x80;
 641             p_spu_data->pi_yuv[i_shade][2] = 0x80;
 642         }
 643
 644 #ifdef DEBUG_SPUDEC
 645         msg_Dbg( p_dec, "using custom palette (border %i, inner %i, shade %i)",
 646                  i_border, i_inner, i_shade );
 647 #endif
 648     }
 649
 650     return VLC_SUCCESS;
 651 }
 652
 653 static void Render( decoder_t *p_dec, subpicture_t *p_spu,
 654                     subpicture_data_t *p_spu_data,
 655                     const spu_properties_t *p_spu_properties )
 656 {
 657     uint8_t *p_p;
 658     int i_x, i_y, i_len, i_color, i_pitch;
 659     uint16_t *p_source = (uint16_t *)p_spu_data->p_data;
 660     video_format_t fmt;
 661
 662     /* Create a new subpicture region */
 663     memset( &fmt, 0, sizeof(video_format_t) );
 664     fmt.i_chroma = VLC_FOURCC('Y','U','V','P');
 665     fmt.i_aspect = 0; /* 0 means use aspect ratio of background video */
 666     fmt.i_width = fmt.i_visible_width = p_spu_properties->i_width;
 667     fmt.i_height = fmt.i_visible_height = p_spu_properties->i_height -
 668         p_spu_data->i_y_top_offset - p_spu_data->i_y_bottom_offset;
 669     fmt.i_x_offset = fmt.i_y_offset = 0;
 670     p_spu->p_region = p_spu->pf_create_region( VLC_OBJECT(p_dec), &fmt );
 671     if( !p_spu->p_region )
 672     {
 673         msg_Err( p_dec, "cannot allocate SPU region" );
 674         return;
 675     }
 676
 677     p_spu->p_region->i_x = p_spu_properties->i_x;
 678     p_spu->p_region->i_y = p_spu_properties->i_y + p_spu_data->i_y_top_offset;
 679     p_p = p_spu->p_region->picture.p->p_pixels;
 680     i_pitch = p_spu->p_region->picture.p->i_pitch;
 681
 682     /* Build palette */
 683     fmt.p_palette->i_entries = 4;
 684     for( i_x = 0; i_x < fmt.p_palette->i_entries; i_x++ )
 685     {
 686         fmt.p_palette->palette[i_x][0] = p_spu_data->pi_yuv[i_x][0];
 687         fmt.p_palette->palette[i_x][1] = p_spu_data->pi_yuv[i_x][1];
 688         fmt.p_palette->palette[i_x][2] = p_spu_data->pi_yuv[i_x][2];
 689         fmt.p_palette->palette[i_x][3] =
 690             p_spu_data->pi_alpha[i_x] == 0xf ? 0xff :
 691             p_spu_data->pi_alpha[i_x] << 4;
 692     }
 693
 694     /* Draw until we reach the bottom of the subtitle */
 695     for( i_y = 0; i_y < (int)fmt.i_height * i_pitch; i_y += i_pitch )
 696     {
 697         /* Draw until we reach the end of the line */
 698         for( i_x = 0 ; i_x < (int)fmt.i_width; i_x += i_len )
 699         {
 700             /* Get the RLE part, then draw the line */
 701             i_color = *p_source & 0x3;
 702             i_len = *p_source++ >> 2;
 703             memset( p_p + i_x + i_y, i_color, i_len );
 704         }
 705     }
 706 }