modules/codec/spudec/parse.c

   1 /*****************************************************************************
   2  * parse.c: SPU parser
   3  *****************************************************************************
   4  * Copyright (C) 2000-2001, 2005, 2006 VLC authors and VideoLAN
   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 it
  12  * under the terms of the GNU Lesser General Public License as published by
  13  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this program; if not, write to the Free Software Foundation,
  23  * 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_codec.h>
  35 #include <vlc_input.h>
  36
  37 #include "spudec.h"
  38
  39 /*****************************************************************************
  40  * Local prototypes.
  41  *****************************************************************************/
  42 typedef struct
  43 {
  44     int i_width;
  45     int i_height;
  46     int i_x;
  47     int i_y;
  48 } spu_properties_t;
  49
  50 typedef struct
  51 {
  52     int   pi_offset[2];                              /* byte offsets to data */
  53     uint16_t *p_data;
  54
  55     /* Color information */
  56     bool b_palette;
  57     uint8_t    pi_alpha[4];
  58     uint8_t    pi_yuv[4][3];
  59
  60     /* Auto crop fullscreen subtitles */
  61     bool b_auto_crop;
  62     int i_y_top_offset;
  63     int i_y_bottom_offset;
  64
  65 } subpicture_data_t;
  66
  67 static int  ParseControlSeq( decoder_t *, subpicture_t *, subpicture_data_t *,
  68                              spu_properties_t *, mtime_t i_pts );
  69 static int  ParseRLE       ( decoder_t *, subpicture_data_t *,
  70                              const spu_properties_t * );
  71 static void Render         ( decoder_t *, subpicture_t *, subpicture_data_t *,
  72                              const spu_properties_t * );
  73
  74 /*****************************************************************************
  75  * AddNibble: read a nibble from a source packet and add it to our integer.
  76  *****************************************************************************/
  77 static inline unsigned int AddNibble( unsigned int i_code,
  78                                       const uint8_t *p_src, unsigned int *pi_index )
  79 {
  80     if( *pi_index & 0x1 )
  81     {
  82         return( i_code << 4 | ( p_src[(*pi_index)++ >> 1] & 0xf ) );
  83     }
  84     else
  85     {
  86         return( i_code << 4 | p_src[(*pi_index)++ >> 1] >> 4 );
  87     }
  88 }
  89
  90 /*****************************************************************************
  91  * ParsePacket: parse an SPU packet and send it to the video output
  92  *****************************************************************************
  93  * This function parses the SPU packet and, if valid, sends it to the
  94  * video output.
  95  *****************************************************************************/
  96 subpicture_t * ParsePacket( decoder_t *p_dec )
  97 {
  98     decoder_sys_t *p_sys = p_dec->p_sys;
  99     subpicture_t *p_spu;
 100     subpicture_data_t spu_data;
 101     spu_properties_t spu_properties;
 102
 103     /* Allocate the subpicture internal data. */
 104     p_spu = decoder_NewSubpicture( p_dec, NULL );
 105     if( !p_spu ) return NULL;
 106
 107     p_spu->i_original_picture_width =
 108         p_dec->fmt_in.subs.spu.i_original_frame_width;
 109     p_spu->i_original_picture_height =
 110         p_dec->fmt_in.subs.spu.i_original_frame_height;
 111
 112     /* Getting the control part */
 113     if( ParseControlSeq( p_dec, p_spu, &spu_data, &spu_properties, p_sys->i_pts ) )
 114     {
 115         /* There was a parse error, delete the subpicture */
 116         subpicture_Delete( p_spu );
 117         return NULL;
 118     }
 119
 120     /* we are going to expand the RLE stuff so that we won't need to read
 121      * nibbles later on. This will speed things up a lot. Plus, we'll only
 122      * need to do this stupid interlacing stuff once.
 123      *
 124      * Rationale for the "p_spudec->i_rle_size * 4*sizeof(*spu_data.p_data)":
 125      *  one byte gaves two nibbles and may be used twice (once per field)
 126      * generating 4 codes.
 127      */
 128     spu_data.p_data = malloc( sizeof(*spu_data.p_data) * 2 * 2 * p_sys->i_rle_size );
 129
 130     /* We try to display it */
 131     if( ParseRLE( p_dec, &spu_data, &spu_properties ) )
 132     {
 133         /* There was a parse error, delete the subpicture */
 134         subpicture_Delete( p_spu );
 135         free( spu_data.p_data );
 136         return NULL;
 137     }
 138
 139 #ifdef DEBUG_SPUDEC
 140     msg_Dbg( p_dec, "total size: 0x%x, RLE offsets: 0x%x 0x%x",
 141              p_sys->i_spu_size,
 142              spu_data.pi_offset[0], spu_data.pi_offset[1] );
 143 #endif
 144
 145     Render( p_dec, p_spu, &spu_data, &spu_properties );
 146     free( spu_data.p_data );
 147
 148     return p_spu;
 149 }
 150
 151 /*****************************************************************************
 152  * ParseControlSeq: parse all SPU control sequences
 153  *****************************************************************************
 154  * This is the most important part in SPU decoding. We get dates, palette
 155  * information, coordinates, and so on. For more information on the
 156  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 157  *****************************************************************************/
 158 static int ParseControlSeq( decoder_t *p_dec, subpicture_t *p_spu,
 159                             subpicture_data_t *p_spu_data, spu_properties_t *p_spu_properties, mtime_t i_pts )
 160 {
 161     decoder_sys_t *p_sys = p_dec->p_sys;
 162
 163     /* Our current index in the SPU packet */
 164     unsigned int i_index;
 165
 166     /* The next start-of-control-sequence index and the previous one */
 167     unsigned int i_next_seq = 0, i_cur_seq = 0;
 168
 169     /* Command and date */
 170     uint8_t i_command = SPU_CMD_END;
 171     mtime_t date = 0;
 172     bool b_cmd_offset = false;
 173     bool b_cmd_alpha = false;
 174     subpicture_data_t spu_data_cmd;
 175
 176     if( !p_spu || !p_spu_data )
 177         return VLC_EGENERIC;
 178
 179     /* Create working space for spu data */
 180     memset( &spu_data_cmd, 0, sizeof(spu_data_cmd) );
 181     spu_data_cmd.pi_offset[0] = -1;
 182     spu_data_cmd.pi_offset[1] = -1;
 183     spu_data_cmd.p_data = NULL;
 184     spu_data_cmd.b_palette = false;
 185     spu_data_cmd.b_auto_crop = false;
 186     spu_data_cmd.i_y_top_offset = 0;
 187     spu_data_cmd.i_y_bottom_offset = 0;
 188     spu_data_cmd.pi_alpha[0] = 0x00;
 189     spu_data_cmd.pi_alpha[1] = 0x0f;
 190     spu_data_cmd.pi_alpha[2] = 0x0f;
 191     spu_data_cmd.pi_alpha[3] = 0x0f;
 192
 193     /* Initialize the structure */
 194     p_spu->i_start = p_spu->i_stop = 0;
 195     p_spu->b_ephemer = false;
 196
 197     memset( p_spu_properties, 0, sizeof(*p_spu_properties) );
 198
 199     /* */
 200     *p_spu_data = spu_data_cmd;
 201
 202     for( i_index = 4 + p_sys->i_rle_size; i_index < p_sys->i_spu_size ; )
 203     {
 204         /* If we just read a command sequence, read the next one;
 205          * otherwise, go on with the commands of the current sequence. */
 206         if( i_command == SPU_CMD_END )
 207         {
 208             if( i_index + 4 > p_sys->i_spu_size )
 209             {
 210                 msg_Err( p_dec, "overflow in SPU command sequence" );
 211                 return VLC_EGENERIC;
 212             }
 213
 214             /* */
 215             b_cmd_offset = false;
 216             b_cmd_alpha = false;
 217             /* Get the control sequence date */
 218             date = (mtime_t)GetWBE( &p_sys->buffer[i_index] ) * 11000;
 219
 220             /* Next offset */
 221             i_cur_seq = i_index;
 222             i_next_seq = GetWBE( &p_sys->buffer[i_index+2] );
 223
 224             if( i_next_seq > p_sys->i_spu_size )
 225             {
 226                 msg_Err( p_dec, "overflow in SPU next command sequence" );
 227                 return VLC_EGENERIC;
 228             }
 229
 230             /* Skip what we just read */
 231             i_index += 4;
 232         }
 233
 234         i_command = p_sys->buffer[i_index];
 235
 236         switch( i_command )
 237         {
 238         case SPU_CMD_FORCE_DISPLAY: /* 00 (force displaying) */
 239             p_spu->i_start = i_pts + date;
 240             p_spu->b_ephemer = true;
 241             /* ignores picture date as display start time
 242              * works around non displayable (offset by few ms)
 243              * spu menu over still frame in SPU_Select */
 244             p_spu->b_subtitle = false;
 245             i_index += 1;
 246             break;
 247
 248         /* Convert the dates in seconds to PTS values */
 249         case SPU_CMD_START_DISPLAY: /* 01 (start displaying) */
 250             p_spu->i_start = i_pts + date;
 251             i_index += 1;
 252             break;
 253
 254         case SPU_CMD_STOP_DISPLAY: /* 02 (stop displaying) */
 255             p_spu->i_stop = i_pts + date;
 256             i_index += 1;
 257             break;
 258
 259         case SPU_CMD_SET_PALETTE:
 260             /* 03xxxx (palette) */
 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             if( p_dec->fmt_in.subs.spu.palette[0] == 0xBeeF )
 268             {
 269                 unsigned int idx[4];
 270                 int i;
 271
 272                 spu_data_cmd.b_palette = true;
 273
 274                 idx[0] = (p_sys->buffer[i_index+1]>>4)&0x0f;
 275                 idx[1] = (p_sys->buffer[i_index+1])&0x0f;
 276                 idx[2] = (p_sys->buffer[i_index+2]>>4)&0x0f;
 277                 idx[3] = (p_sys->buffer[i_index+2])&0x0f;
 278
 279                 for( i = 0; i < 4 ; i++ )
 280                 {
 281                     uint32_t i_color = p_dec->fmt_in.subs.spu.palette[1+idx[i]];
 282
 283                     /* FIXME: this job should be done sooner */
 284                     spu_data_cmd.pi_yuv[3-i][0] = (i_color>>16) & 0xff;
 285                     spu_data_cmd.pi_yuv[3-i][1] = (i_color>>0) & 0xff;
 286                     spu_data_cmd.pi_yuv[3-i][2] = (i_color>>8) & 0xff;
 287                 }
 288             }
 289
 290             i_index += 3;
 291             break;
 292
 293         case SPU_CMD_SET_ALPHACHANNEL: /* 04xxxx (alpha channel) */
 294             if( i_index + 3 > p_sys->i_spu_size )
 295             {
 296                 msg_Err( p_dec, "overflow in SPU command" );
 297                 return VLC_EGENERIC;
 298             }
 299
 300             if(!p_sys->b_disabletrans)
 301             { /* If we want to use original transparency values */
 302                 b_cmd_alpha = true;
 303                 spu_data_cmd.pi_alpha[3] = (p_sys->buffer[i_index+1]>>4)&0x0f;
 304                 spu_data_cmd.pi_alpha[2] = (p_sys->buffer[i_index+1])&0x0f;
 305                 spu_data_cmd.pi_alpha[1] = (p_sys->buffer[i_index+2]>>4)&0x0f;
 306                 spu_data_cmd.pi_alpha[0] = (p_sys->buffer[i_index+2])&0x0f;
 307             }
 308
 309             i_index += 3;
 310             break;
 311
 312         case SPU_CMD_SET_COORDINATES: /* 05xxxyyyxxxyyy (coordinates) */
 313             if( i_index + 7 > p_sys->i_spu_size )
 314             {
 315                 msg_Err( p_dec, "overflow in SPU command" );
 316                 return VLC_EGENERIC;
 317             }
 318
 319             p_spu_properties->i_x = (p_sys->buffer[i_index+1]<<4)|
 320                          ((p_sys->buffer[i_index+2]>>4)&0x0f);
 321             p_spu_properties->i_width = (((p_sys->buffer[i_index+2]&0x0f)<<8)|
 322                               p_sys->buffer[i_index+3]) - p_spu_properties->i_x + 1;
 323
 324             p_spu_properties->i_y = (p_sys->buffer[i_index+4]<<4)|
 325                          ((p_sys->buffer[i_index+5]>>4)&0x0f);
 326             p_spu_properties->i_height = (((p_sys->buffer[i_index+5]&0x0f)<<8)|
 327                               p_sys->buffer[i_index+6]) - p_spu_properties->i_y + 1;
 328
 329             /* Auto crop fullscreen subtitles */
 330             if( p_spu_properties->i_height > 250 )
 331                 p_spu_data->b_auto_crop = true;
 332
 333             i_index += 7;
 334             break;
 335
 336         case SPU_CMD_SET_OFFSETS: /* 06xxxxyyyy (byte offsets) */
 337             if( i_index + 5 > p_sys->i_spu_size )
 338             {
 339                 msg_Err( p_dec, "overflow in SPU command" );
 340                 return VLC_EGENERIC;
 341             }
 342
 343             b_cmd_offset = true;
 344             p_spu_data->pi_offset[0] = GetWBE(&p_sys->buffer[i_index+1]) - 4;
 345             p_spu_data->pi_offset[1] = GetWBE(&p_sys->buffer[i_index+3]) - 4;
 346             i_index += 5;
 347             break;
 348
 349         case SPU_CMD_END: /* ff (end) */
 350             if( b_cmd_offset )
 351             {
 352                 /* It seems that palette and alpha from the block having
 353                  * the cmd offset have to be used
 354                  * XXX is it all ? */
 355                 p_spu_data->b_palette = spu_data_cmd.b_palette;
 356                 if( spu_data_cmd.b_palette )
 357                     memcpy( p_spu_data->pi_yuv, spu_data_cmd.pi_yuv, sizeof(spu_data_cmd.pi_yuv) );
 358                 if( b_cmd_alpha )
 359                     memcpy( p_spu_data->pi_alpha, spu_data_cmd.pi_alpha, sizeof(spu_data_cmd.pi_alpha) );
 360             }
 361
 362             i_index += 1;
 363             break;
 364
 365         default: /* xx (unknown command) */
 366             msg_Warn( p_dec, "unknown SPU command 0x%.2x", i_command );
 367             if( i_index + 1 < i_next_seq )
 368             {
 369                  /* There is at least one other command sequence */
 370                  if( p_sys->buffer[i_next_seq - 1] == SPU_CMD_END )
 371                  {
 372                      /* This is consistent. Skip to that command sequence. */
 373                      i_index = i_next_seq;
 374                  }
 375                  else
 376                  {
 377                      /* There were other commands. */
 378                      msg_Warn( p_dec, "cannot recover, dropping subtitle" );
 379                      return VLC_EGENERIC;
 380                  }
 381             }
 382             else
 383             {
 384                 /* We were in the last command sequence. Stop parsing by
 385                  * pretending we met an SPU_CMD_END command. */
 386                 i_command = SPU_CMD_END;
 387                 i_index++;
 388             }
 389         }
 390
 391         /* */
 392         if( i_command == SPU_CMD_END && i_index != i_next_seq )
 393             break;
 394     }
 395
 396     /* Check that the next sequence index matches the current one */
 397     if( i_next_seq != i_cur_seq )
 398     {
 399         msg_Err( p_dec, "index mismatch (0x%.4x != 0x%.4x)",
 400                  i_next_seq, i_cur_seq );
 401         return VLC_EGENERIC;
 402     }
 403
 404     if( i_index > p_sys->i_spu_size )
 405     {
 406         msg_Err( p_dec, "uh-oh, we went too far (0x%.4x > 0x%.4x)",
 407                  i_index, p_sys->i_spu_size );
 408         return VLC_EGENERIC;
 409     }
 410
 411     const int i_spu_size = p_sys->i_spu - 4;
 412     if( p_spu_data->pi_offset[0] < 0 || p_spu_data->pi_offset[0] >= i_spu_size ||
 413         p_spu_data->pi_offset[1] < 0 || p_spu_data->pi_offset[1] >= i_spu_size )
 414     {
 415         msg_Err( p_dec, "invalid offset values" );
 416         return VLC_EGENERIC;
 417     }
 418
 419     if( !p_spu->i_start )
 420     {
 421         msg_Err( p_dec, "no `start display' command" );
 422         return VLC_EGENERIC;
 423     }
 424
 425     if( p_spu->i_stop <= p_spu->i_start && !p_spu->b_ephemer )
 426     {
 427         /* This subtitle will live for 5 seconds or until the next subtitle */
 428         p_spu->i_stop = p_spu->i_start + (mtime_t)500 * 11000;
 429         p_spu->b_ephemer = true;
 430     }
 431
 432     /* Get rid of padding bytes */
 433     if( p_sys->i_spu_size > i_index + 1 )
 434     {
 435         /* Zero or one padding byte are quite usual
 436          * More than one padding byte - this is very strange, but
 437          * we can ignore them. */
 438         msg_Warn( p_dec, "%i padding bytes, we usually get 0 or 1 of them",
 439                   p_sys->i_spu_size - i_index );
 440     }
 441
 442     /* Successfully parsed ! */
 443     return VLC_SUCCESS;
 444 }
 445
 446 /*****************************************************************************
 447  * ParseRLE: parse the RLE part of the subtitle
 448  *****************************************************************************
 449  * This part parses the subtitle graphical data and stores it in a more
 450  * convenient structure for later decoding. For more information on the
 451  * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
 452  *****************************************************************************/
 453 static int ParseRLE( decoder_t *p_dec,
 454                      subpicture_data_t *p_spu_data,
 455                      const spu_properties_t *p_spu_properties )
 456 {
 457     decoder_sys_t *p_sys = p_dec->p_sys;
 458
 459     const unsigned int i_width = p_spu_properties->i_width;
 460     const unsigned int i_height = p_spu_properties->i_height;
 461     unsigned int i_x, i_y;
 462
 463     uint16_t *p_dest = p_spu_data->p_data;
 464
 465     /* The subtitles are interlaced, we need two offsets */
 466     unsigned int  i_id = 0;                   /* Start on the even SPU layer */
 467     unsigned int  pi_table[ 2 ];
 468     unsigned int *pi_offset;
 469
 470     /* Cropping */
 471     bool b_empty_top = true;
 472     unsigned int i_skipped_top = 0, i_skipped_bottom = 0;
 473     unsigned int i_transparent_code = 0;
 474
 475     /* Colormap statistics */
 476     int i_border = -1;
 477     int stats[4]; stats[0] = stats[1] = stats[2] = stats[3] = 0;
 478
 479     pi_table[ 0 ] = p_spu_data->pi_offset[ 0 ] << 1;
 480     pi_table[ 1 ] = p_spu_data->pi_offset[ 1 ] << 1;
 481
 482     for( i_y = 0 ; i_y < i_height ; i_y++ )
 483     {
 484         unsigned int i_code;
 485         pi_offset = pi_table + i_id;
 486
 487         for( i_x = 0 ; i_x < i_width ; i_x += i_code >> 2 )
 488         {
 489             i_code = 0;
 490             for( unsigned int i_min = 1; i_min <= 0x40 && i_code < i_min; i_min <<= 2 )
 491             {
 492                 if( (*pi_offset >> 1) >= p_sys->i_spu_size )
 493                 {
 494                     msg_Err( p_dec, "out of bounds while reading rle" );
 495                     return VLC_EGENERIC;
 496                 }
 497                 i_code = AddNibble( i_code, &p_sys->buffer[4], pi_offset );
 498             }
 499             if( i_code < 0x0004 )
 500             {
 501                 /* If the 14 first bits are set to 0, then it's a
 502                  * new line. We emulate it. */
 503                 i_code |= ( i_width - i_x ) << 2;
 504             }
 505
 506             if( ( (i_code >> 2) + i_x + i_y * i_width ) > i_height * i_width )
 507             {
 508                 msg_Err( p_dec, "out of bounds, %i at (%i,%i) is out of %ix%i",
 509                          i_code >> 2, i_x, i_y, i_width, i_height );
 510                 return VLC_EGENERIC;
 511             }
 512
 513             /* Try to find the border color */
 514             if( p_spu_data->pi_alpha[ i_code & 0x3 ] != 0x00 )
 515             {
 516                 i_border = i_code & 0x3;
 517                 stats[i_border] += i_code >> 2;
 518             }
 519
 520             /* Auto crop subtitles (a lot more optimized) */
 521             if( p_spu_data->b_auto_crop )
 522             {
 523                 if( !i_y )
 524                 {
 525                     /* We assume that if the first line is transparent, then
 526                      * it is using the palette index for the
 527                      * (background) transparent color */
 528                     if( (i_code >> 2) == i_width &&
 529                         p_spu_data->pi_alpha[ i_code & 0x3 ] == 0x00 )
 530                     {
 531                         i_transparent_code = i_code;
 532                     }
 533                     else
 534                     {
 535                         p_spu_data->b_auto_crop = false;
 536                     }
 537                 }
 538
 539                 if( i_code == i_transparent_code )
 540                 {
 541                     if( b_empty_top )
 542                     {
 543                         /* This is a blank top line, we skip it */
 544                       i_skipped_top++;
 545                     }
 546                     else
 547                     {
 548                         /* We can't be sure the current lines will be skipped,
 549                          * so we store the code just in case. */
 550                       *p_dest++ = i_code;
 551                       i_skipped_bottom++;
 552                     }
 553                 }
 554                 else
 555                 {
 556                     /* We got a valid code, store it */
 557                     *p_dest++ = i_code;
 558
 559                     /* Valid code means no blank line */
 560                     b_empty_top = false;
 561                     i_skipped_bottom = 0;
 562                 }
 563             }
 564             else
 565             {
 566                 *p_dest++ = i_code;
 567             }
 568         }
 569
 570         /* Check that we didn't go too far */
 571         if( i_x > i_width )
 572         {
 573             msg_Err( p_dec, "i_x overflowed, %i > %i", i_x, i_width );
 574             return VLC_EGENERIC;
 575         }
 576
 577         /* Byte-align the stream */
 578         if( *pi_offset & 0x1 )
 579         {
 580             (*pi_offset)++;
 581         }
 582
 583         /* Swap fields */
 584         i_id = ~i_id & 0x1;
 585     }
 586
 587     /* We shouldn't get any padding bytes */
 588     if( i_y < i_height )
 589     {
 590         msg_Err( p_dec, "padding bytes found in RLE sequence" );
 591         msg_Err( p_dec, "send mail to <sam@zoy.org> if you "
 592                         "want to help debugging this" );
 593
 594         /* Skip them just in case */
 595         while( i_y < i_height )
 596         {
 597             *p_dest++ = i_width << 2;
 598             i_y++;
 599         }
 600
 601         return VLC_EGENERIC;
 602     }
 603
 604 #ifdef DEBUG_SPUDEC
 605     msg_Dbg( p_dec, "valid subtitle, size: %ix%i, position: %i,%i",
 606              p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y );
 607 #endif
 608
 609     /* Crop if necessary */
 610     if( i_skipped_top || i_skipped_bottom )
 611     {
 612 #ifdef DEBUG_SPUDEC
 613         int i_y = p_spu->i_y + i_skipped_top;
 614         int i_height = p_spu->i_height - (i_skipped_top + i_skipped_bottom);
 615 #endif
 616         p_spu_data->i_y_top_offset = i_skipped_top;
 617         p_spu_data->i_y_bottom_offset = i_skipped_bottom;
 618 #ifdef DEBUG_SPUDEC
 619         msg_Dbg( p_dec, "cropped to: %ix%i, position: %i,%i",
 620                  p_spu->i_width, i_height, p_spu->i_x, i_y );
 621 #endif
 622     }
 623
 624     /* Handle color if no palette was found */
 625     if( !p_spu_data->b_palette )
 626     {
 627         int i, i_inner = -1, i_shade = -1;
 628
 629         /* Set the border color */
 630         if( i_border != -1 )
 631         {
 632             p_spu_data->pi_yuv[i_border][0] = 0x00;
 633             p_spu_data->pi_yuv[i_border][1] = 0x80;
 634             p_spu_data->pi_yuv[i_border][2] = 0x80;
 635             stats[i_border] = 0;
 636         }
 637
 638         /* Find the inner colors */
 639         for( i = 0 ; i < 4 && i_inner == -1 ; i++ )
 640         {
 641             if( stats[i] )
 642             {
 643                 i_inner = i;
 644             }
 645         }
 646
 647         for(       ; i < 4 && i_shade == -1 ; i++ )
 648         {
 649             if( stats[i] )
 650             {
 651                 if( stats[i] > stats[i_inner] )
 652                 {
 653                     i_shade = i_inner;
 654                     i_inner = i;
 655                 }
 656                 else
 657                 {
 658                     i_shade = i;
 659                 }
 660             }
 661         }
 662
 663         /* Set the inner color */
 664         if( i_inner != -1 )
 665         {
 666             p_spu_data->pi_yuv[i_inner][0] = 0xff;
 667             p_spu_data->pi_yuv[i_inner][1] = 0x80;
 668             p_spu_data->pi_yuv[i_inner][2] = 0x80;
 669         }
 670
 671         /* Set the anti-aliasing color */
 672         if( i_shade != -1 )
 673         {
 674             p_spu_data->pi_yuv[i_shade][0] = 0x80;
 675             p_spu_data->pi_yuv[i_shade][1] = 0x80;
 676             p_spu_data->pi_yuv[i_shade][2] = 0x80;
 677         }
 678
 679 #ifdef DEBUG_SPUDEC
 680         msg_Dbg( p_dec, "using custom palette (border %i, inner %i, shade %i)",
 681                  i_border, i_inner, i_shade );
 682 #endif
 683     }
 684
 685     return VLC_SUCCESS;
 686 }
 687
 688 static void Render( decoder_t *p_dec, subpicture_t *p_spu,
 689                     subpicture_data_t *p_spu_data,
 690                     const spu_properties_t *p_spu_properties )
 691 {
 692     uint8_t *p_p;
 693     int i_x, i_y, i_len, i_color, i_pitch;
 694     const uint16_t *p_source = p_spu_data->p_data;
 695     video_format_t fmt;
 696     video_palette_t palette;
 697
 698     /* Create a new subpicture region */
 699     video_format_Init( &fmt, VLC_CODEC_YUVP );
 700     fmt.i_sar_num = 0; /* 0 means use aspect ratio of background video */
 701     fmt.i_sar_den = 1;
 702     fmt.i_width = fmt.i_visible_width = p_spu_properties->i_width;
 703     fmt.i_height = fmt.i_visible_height = p_spu_properties->i_height -
 704         p_spu_data->i_y_top_offset - p_spu_data->i_y_bottom_offset;
 705     fmt.i_x_offset = fmt.i_y_offset = 0;
 706     fmt.p_palette = &palette;
 707     fmt.p_palette->i_entries = 4;
 708     for( i_x = 0; i_x < fmt.p_palette->i_entries; i_x++ )
 709     {
 710         fmt.p_palette->palette[i_x][0] = p_spu_data->pi_yuv[i_x][0];
 711         fmt.p_palette->palette[i_x][1] = p_spu_data->pi_yuv[i_x][1];
 712         fmt.p_palette->palette[i_x][2] = p_spu_data->pi_yuv[i_x][2];
 713         fmt.p_palette->palette[i_x][3] = p_spu_data->pi_alpha[i_x] * 0x11;
 714     }
 715
 716     p_spu->p_region = subpicture_region_New( &fmt );
 717     if( !p_spu->p_region )
 718     {
 719         fmt.p_palette = NULL;
 720         video_format_Clean( &fmt );
 721         msg_Err( p_dec, "cannot allocate SPU region" );
 722         return;
 723     }
 724
 725     p_spu->p_region->i_x = p_spu_properties->i_x;
 726     p_spu->p_region->i_y = p_spu_properties->i_y + p_spu_data->i_y_top_offset;
 727     p_p = p_spu->p_region->p_picture->p->p_pixels;
 728     i_pitch = p_spu->p_region->p_picture->p->i_pitch;
 729
 730     /* Draw until we reach the bottom of the subtitle */
 731     for( i_y = 0; i_y < (int)fmt.i_height * i_pitch; i_y += i_pitch )
 732     {
 733         /* Draw until we reach the end of the line */
 734         for( i_x = 0 ; i_x < (int)fmt.i_width; i_x += i_len )
 735         {
 736             /* Get the RLE part, then draw the line */
 737             i_color = *p_source & 0x3;
 738             i_len = *p_source++ >> 2;
 739             memset( p_p + i_x + i_y, i_color, i_len );
 740         }
 741     }
 742
 743     fmt.p_palette = NULL;
 744     video_format_Clean( &fmt );
 745 }