git.sesse.net Git - vlc/blob - modules/codec/subtitles/subsusf.c

   1 /*****************************************************************************
   2  * subsusf.c : USF subtitles decoder
   3  *****************************************************************************
   4  * Copyright (C) 2000-2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Bernie Purcell <bitmap@videolan.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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #include "subsdec.h"
  25
  26 /*****************************************************************************
  27  * Local prototypes
  28  *****************************************************************************/
  29 static int  OpenDecoder   ( vlc_object_t * );
  30 static void CloseDecoder  ( vlc_object_t * );
  31
  32 static subpicture_t *DecodeBlock   ( decoder_t *, block_t ** );
  33 static char         *CreatePlainText( char * );
  34 static int           ParseImageAttachments( decoder_t *p_dec );
  35
  36 static subpicture_t        *ParseText     ( decoder_t *, block_t * );
  37 static void                 ParseUSFHeader( decoder_t * );
  38 static subpicture_region_t *ParseUSFString( decoder_t *, char *, subpicture_t * );
  39 static subpicture_region_t *LoadEmbeddedImage( decoder_t *p_dec, subpicture_t *p_spu, const char *psz_filename, int i_transparent_color );
  40
  41 /*****************************************************************************
  42  * Module descriptor.
  43  *****************************************************************************/
  44
  45 vlc_module_begin();
  46     set_capability( "decoder", 40 );
  47     set_callbacks( OpenDecoder, CloseDecoder );
  48     set_category( CAT_INPUT );
  49     set_subcategory( SUBCAT_INPUT_SCODEC );
  50     /* We inherit subsdec-align and subsdec-formatted from subsdec.c */
  51 vlc_module_end();
  52
  53 /*****************************************************************************
  54  * OpenDecoder: probe the decoder and return score
  55  *****************************************************************************
  56  * Tries to launch a decoder and return score so that the interface is able
  57  * to chose.
  58  *****************************************************************************/
  59 static int OpenDecoder( vlc_object_t *p_this )
  60 {
  61     decoder_t     *p_dec = (decoder_t*)p_this;
  62     decoder_sys_t *p_sys;
  63     vlc_value_t    val;
  64
  65     if( p_dec->fmt_in.i_codec != VLC_FOURCC('u','s','f',' ') )
  66     {
  67         return VLC_EGENERIC;
  68     }
  69
  70     p_dec->pf_decode_sub = DecodeBlock;
  71
  72     /* Allocate the memory needed to store the decoder's structure */
  73     if( ( p_dec->p_sys = p_sys =
  74           (decoder_sys_t *)calloc(1, sizeof(decoder_sys_t)) ) == NULL )
  75     {
  76         msg_Err( p_dec, "out of memory" );
  77         return VLC_ENOMEM;
  78     }
  79
  80     /* Unused fields of p_sys - not needed for USF decoding */
  81     p_sys->b_ass = VLC_FALSE;
  82     p_sys->iconv_handle = (vlc_iconv_t)-1;
  83     p_sys->b_autodetect_utf8 = VLC_FALSE;
  84
  85     /* init of p_sys */
  86     p_sys->i_align = 0;
  87     p_sys->i_original_height = -1;
  88     p_sys->i_original_width = -1;
  89     TAB_INIT( p_sys->i_ssa_styles, p_sys->pp_ssa_styles );
  90     TAB_INIT( p_sys->i_images, p_sys->pp_images );
  91
  92     /* USF subtitles are mandated to be UTF-8, so don't need vlc_iconv */
  93
  94     var_Create( p_dec, "subsdec-align", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
  95     var_Get( p_dec, "subsdec-align", &val );
  96     p_sys->i_align = val.i_int;
  97
  98     ParseImageAttachments( p_dec );
  99
 100     if( var_CreateGetBool( p_dec, "subsdec-formatted" ) )
 101     {
 102         if( p_dec->fmt_in.i_extra > 0 )
 103             ParseUSFHeader( p_dec );
 104     }
 105
 106     return VLC_SUCCESS;
 107 }
 108
 109 /****************************************************************************
 110  * DecodeBlock: the whole thing
 111  ****************************************************************************
 112  * This function must be fed with complete subtitles units.
 113  ****************************************************************************/
 114 static subpicture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 115 {
 116     subpicture_t *p_spu = NULL;
 117
 118     if( !pp_block || *pp_block == NULL ) return NULL;
 119
 120     p_spu = ParseText( p_dec, *pp_block );
 121
 122     block_Release( *pp_block );
 123     *pp_block = NULL;
 124
 125     return p_spu;
 126 }
 127
 128 /*****************************************************************************
 129  * CloseDecoder: clean up the decoder
 130  *****************************************************************************/
 131 static void CloseDecoder( vlc_object_t *p_this )
 132 {
 133     decoder_t *p_dec = (decoder_t *)p_this;
 134     decoder_sys_t *p_sys = p_dec->p_sys;
 135
 136     if( p_sys->pp_ssa_styles )
 137     {
 138         int i;
 139         for( i = 0; i < p_sys->i_ssa_styles; i++ )
 140         {
 141             if( !p_sys->pp_ssa_styles[i] )
 142                 continue;
 143
 144             if( p_sys->pp_ssa_styles[i]->psz_stylename )
 145                 free( p_sys->pp_ssa_styles[i]->psz_stylename );
 146             if( p_sys->pp_ssa_styles[i]->font_style.psz_fontname )
 147                 free( p_sys->pp_ssa_styles[i]->font_style.psz_fontname );
 148             if( p_sys->pp_ssa_styles[i] )
 149                 free( p_sys->pp_ssa_styles[i] );
 150         }
 151         TAB_CLEAN( p_sys->i_ssa_styles, p_sys->pp_ssa_styles );
 152     }
 153     if( p_sys->pp_images )
 154     {
 155         int i;
 156         for( i = 0; i < p_sys->i_images; i++ )
 157         {
 158             if( !p_sys->pp_images[i] )
 159                 continue;
 160
 161             if( p_sys->pp_images[i]->p_pic )
 162                 p_sys->pp_images[i]->p_pic->pf_release( p_sys->pp_images[i]->p_pic );
 163             if( p_sys->pp_images[i]->psz_filename )
 164                 free( p_sys->pp_images[i]->psz_filename );
 165
 166             free( p_sys->pp_images[i] );
 167         }
 168         TAB_CLEAN( p_sys->i_images, p_sys->pp_images );
 169     }
 170
 171     free( p_sys );
 172 }
 173
 174 /*****************************************************************************
 175  * ParseText: parse an text subtitle packet and send it to the video output
 176  *****************************************************************************/
 177 static subpicture_t *ParseText( decoder_t *p_dec, block_t *p_block )
 178 {
 179     decoder_sys_t *p_sys = p_dec->p_sys;
 180     subpicture_t *p_spu = NULL;
 181     char *psz_subtitle = NULL;
 182
 183     /* We cannot display a subpicture with no date */
 184     if( p_block->i_pts == 0 )
 185     {
 186         msg_Warn( p_dec, "subtitle without a date" );
 187         return NULL;
 188     }
 189
 190     /* Check validity of packet data */
 191     /* An "empty" line containing only \0 can be used to force
 192        and ephemer picture from the screen */
 193     if( p_block->i_buffer < 1 )
 194     {
 195         msg_Warn( p_dec, "no subtitle data" );
 196         return NULL;
 197     }
 198
 199     /* Should be resiliant against bad subtitles */
 200     psz_subtitle = strndup( (const char *)p_block->p_buffer,
 201                             p_block->i_buffer );
 202     if( psz_subtitle == NULL )
 203         return NULL;
 204
 205     /* USF Subtitles are mandated to be UTF-8 -- make sure it is */
 206     if (EnsureUTF8( psz_subtitle ) == NULL)
 207     {
 208         msg_Err( p_dec, _("USF subtitles must be in UTF-8 format.\n"
 209                  "This stream contains USF subtitles which aren't.") );
 210     }
 211
 212     /* Create the subpicture unit */
 213     p_spu = p_dec->pf_spu_buffer_new( p_dec );
 214     if( !p_spu )
 215     {
 216         msg_Warn( p_dec, "can't get spu buffer" );
 217         if( psz_subtitle ) free( psz_subtitle );
 218         return NULL;
 219     }
 220
 221     p_spu->b_pausable = VLC_TRUE;
 222
 223     /* Decode USF strings */
 224     p_spu->p_region = ParseUSFString( p_dec, psz_subtitle, p_spu );
 225
 226     p_spu->i_start = p_block->i_pts;
 227     p_spu->i_stop = p_block->i_pts + p_block->i_length;
 228     p_spu->b_ephemer = (p_block->i_length == 0);
 229     p_spu->b_absolute = VLC_FALSE;
 230     p_spu->i_original_picture_width = p_sys->i_original_width;
 231     p_spu->i_original_picture_height = p_sys->i_original_height;
 232
 233     if( psz_subtitle ) free( psz_subtitle );
 234
 235     return p_spu;
 236 }
 237
 238 static char *GrabAttributeValue( const char *psz_attribute,
 239                                  const char *psz_tag_start )
 240 {
 241     if( psz_attribute && psz_tag_start )
 242     {
 243         char *psz_tag_end = strchr( psz_tag_start, '>' );
 244         char *psz_found   = strcasestr( psz_tag_start, psz_attribute );
 245
 246         if( psz_found )
 247         {
 248             psz_found += strlen( psz_attribute );
 249
 250             if(( *(psz_found++) == '=' ) &&
 251                ( *(psz_found++) == '\"' ))
 252             {
 253                 if( psz_found < psz_tag_end )
 254                 {
 255                     int   i_len = strcspn( psz_found, "\"" );
 256                     return strndup( psz_found, i_len );
 257                 }
 258             }
 259         }
 260     }
 261     return NULL;
 262 }
 263
 264 static ssa_style_t *ParseStyle( decoder_sys_t *p_sys, char *psz_subtitle )
 265 {
 266     ssa_style_t *p_style   = NULL;
 267     char        *psz_style = GrabAttributeValue( "style", psz_subtitle );
 268
 269     if( psz_style )
 270     {
 271         int i;
 272
 273         for( i = 0; i < p_sys->i_ssa_styles; i++ )
 274         {
 275             if( !strcmp( p_sys->pp_ssa_styles[i]->psz_stylename, psz_style ) )
 276                 p_style = p_sys->pp_ssa_styles[i];
 277         }
 278         free( psz_style );
 279     }
 280     return p_style;
 281 }
 282
 283 static int ParsePositionAttributeList( char *psz_subtitle, int *i_align,
 284                                        int *i_x, int *i_y )
 285 {
 286     int   i_mask = 0;
 287
 288     char *psz_align    = GrabAttributeValue( "alignment", psz_subtitle );
 289     char *psz_margin_x = GrabAttributeValue( "horizontal-margin", psz_subtitle );
 290     char *psz_margin_y = GrabAttributeValue( "vertical-margin", psz_subtitle );
 291     /* -- UNSUPPORTED
 292     char *psz_relative = GrabAttributeValue( "relative-to", psz_subtitle );
 293     char *psz_rotate_x = GrabAttributeValue( "rotate-x", psz_subtitle );
 294     char *psz_rotate_y = GrabAttributeValue( "rotate-y", psz_subtitle );
 295     char *psz_rotate_z = GrabAttributeValue( "rotate-z", psz_subtitle );
 296     */
 297
 298     *i_align = SUBPICTURE_ALIGN_BOTTOM;
 299     *i_x = 0;
 300     *i_y = 0;
 301
 302     if( psz_align )
 303     {
 304         if( !strcasecmp( "TopLeft", psz_align ) )
 305             *i_align = SUBPICTURE_ALIGN_TOP | SUBPICTURE_ALIGN_LEFT;
 306         else if( !strcasecmp( "TopCenter", psz_align ) )
 307             *i_align = SUBPICTURE_ALIGN_TOP;
 308         else if( !strcasecmp( "TopRight", psz_align ) )
 309             *i_align = SUBPICTURE_ALIGN_TOP | SUBPICTURE_ALIGN_RIGHT;
 310         else if( !strcasecmp( "MiddleLeft", psz_align ) )
 311             *i_align = SUBPICTURE_ALIGN_LEFT;
 312         else if( !strcasecmp( "MiddleCenter", psz_align ) )
 313             *i_align = 0;
 314         else if( !strcasecmp( "MiddleRight", psz_align ) )
 315             *i_align = SUBPICTURE_ALIGN_RIGHT;
 316         else if( !strcasecmp( "BottomLeft", psz_align ) )
 317             *i_align = SUBPICTURE_ALIGN_BOTTOM | SUBPICTURE_ALIGN_LEFT;
 318         else if( !strcasecmp( "BottomCenter", psz_align ) )
 319             *i_align = SUBPICTURE_ALIGN_BOTTOM;
 320         else if( !strcasecmp( "BottomRight", psz_align ) )
 321             *i_align = SUBPICTURE_ALIGN_BOTTOM | SUBPICTURE_ALIGN_RIGHT;
 322
 323         i_mask |= ATTRIBUTE_ALIGNMENT;
 324         free( psz_align );
 325     }
 326     if( psz_margin_x )
 327     {
 328         *i_x = atoi( psz_margin_x );
 329         if( strchr( psz_margin_x, '%' ) )
 330             i_mask |= ATTRIBUTE_X_PERCENT;
 331         else
 332             i_mask |= ATTRIBUTE_X;
 333
 334         free( psz_margin_x );
 335     }
 336     if( psz_margin_y )
 337     {
 338         *i_y = atoi( psz_margin_y );
 339         if( strchr( psz_margin_y, '%' ) )
 340             i_mask |= ATTRIBUTE_Y_PERCENT;
 341         else
 342             i_mask |= ATTRIBUTE_Y;
 343
 344         free( psz_margin_y );
 345     }
 346     return i_mask;
 347 }
 348
 349 static void SetupPositions( subpicture_region_t *p_region, char *psz_subtitle )
 350 {
 351     int           i_mask = 0;
 352     int           i_align;
 353     int           i_x, i_y;
 354
 355     i_mask = ParsePositionAttributeList( psz_subtitle, &i_align, &i_x, &i_y );
 356
 357     if( i_mask & ATTRIBUTE_ALIGNMENT )
 358         p_region->i_align = i_align;
 359
 360     /* TODO: Setup % based offsets properly, without adversely affecting
 361      *       everything else in vlc. Will address with separate patch, to
 362      *       prevent this one being any more complicated.
 363      */
 364     if( i_mask & ATTRIBUTE_X )
 365         p_region->i_x = i_x;
 366     else if( i_mask & ATTRIBUTE_X_PERCENT )
 367         p_region->i_x = 0;
 368
 369     if( i_mask & ATTRIBUTE_Y )
 370         p_region->i_y = i_y;
 371     else if( i_mask & ATTRIBUTE_Y_PERCENT )
 372         p_region->i_y = 0;
 373 }
 374
 375 static subpicture_region_t *CreateTextRegion( decoder_t *p_dec,
 376                                               subpicture_t *p_spu,
 377                                               char *psz_subtitle,
 378                                               int i_len,
 379                                               int i_sys_align )
 380 {
 381     decoder_sys_t        *p_sys = p_dec->p_sys;
 382     subpicture_region_t  *p_text_region;
 383     video_format_t        fmt;
 384
 385     /* Create a new subpicture region */
 386     memset( &fmt, 0, sizeof(video_format_t) );
 387     fmt.i_chroma = VLC_FOURCC('T','E','X','T');
 388     fmt.i_aspect = 0;
 389     fmt.i_width = fmt.i_height = 0;
 390     fmt.i_x_offset = fmt.i_y_offset = 0;
 391     p_text_region = p_spu->pf_create_region( VLC_OBJECT(p_dec), &fmt );
 392
 393     if( p_text_region != NULL )
 394     {
 395         ssa_style_t  *p_style = NULL;
 396
 397         p_text_region->psz_text = NULL;
 398         p_text_region->psz_html = strndup( psz_subtitle, i_len );
 399         if( ! p_text_region->psz_html )
 400         {
 401             msg_Err( p_dec, "out of memory" );
 402             p_spu->pf_destroy_region( VLC_OBJECT(p_dec), p_text_region );
 403             return NULL;
 404         }
 405
 406         p_style = ParseStyle( p_sys, p_text_region->psz_html );
 407         if( !p_style )
 408         {
 409             int i;
 410
 411             for( i = 0; i < p_sys->i_ssa_styles; i++ )
 412             {
 413                 if( !strcasecmp( p_sys->pp_ssa_styles[i]->psz_stylename, "Default" ) )
 414                     p_style = p_sys->pp_ssa_styles[i];
 415             }
 416         }
 417
 418         if( p_style )
 419         {
 420             msg_Dbg( p_dec, "style is: %s", p_style->psz_stylename );
 421
 422             p_text_region->p_style = &p_style->font_style;
 423             p_text_region->i_align = p_style->i_align;
 424
 425             /* TODO: Setup % based offsets properly, without adversely affecting
 426              *       everything else in vlc. Will address with separate patch,
 427              *       to prevent this one being any more complicated.
 428
 429                      * p_style->i_margin_percent_h;
 430                      * p_style->i_margin_percent_v;
 431              */
 432             p_text_region->i_x         = p_style->i_margin_h;
 433             p_text_region->i_y         = p_style->i_margin_v;
 434
 435         }
 436         else
 437         {
 438             p_text_region->i_align = SUBPICTURE_ALIGN_BOTTOM | i_sys_align;
 439             p_text_region->i_x = i_sys_align ? 20 : 0;
 440             p_text_region->i_y = 10;
 441         }
 442         /* Look for position arguments which may override the style-based
 443          * defaults.
 444          */
 445         SetupPositions( p_text_region, psz_subtitle );
 446
 447         p_text_region->p_next = NULL;
 448     }
 449     return p_text_region;
 450 }
 451
 452 static int ParseImageAttachments( decoder_t *p_dec )
 453 {
 454     decoder_sys_t        *p_sys = p_dec->p_sys;
 455     input_attachment_t  **pp_attachments;
 456     int                   i_attachments_cnt;
 457     int                   k = 0;
 458
 459     if( VLC_SUCCESS != decoder_GetInputAttachments( p_dec, &pp_attachments, &i_attachments_cnt ))
 460         return VLC_EGENERIC;
 461
 462     for( k = 0; k < i_attachments_cnt; k++ )
 463     {
 464         input_attachment_t *p_attach = pp_attachments[k];
 465
 466         vlc_fourcc_t  type  = 0;
 467
 468         if( ( !strcmp( p_attach->psz_mime, "image/bmp" ) )      || /* BMP */
 469             ( !strcmp( p_attach->psz_mime, "image/x-bmp" ) )    ||
 470             ( !strcmp( p_attach->psz_mime, "image/x-bitmap" ) ) ||
 471             ( !strcmp( p_attach->psz_mime, "image/x-ms-bmp" ) ) )
 472         {
 473              type = VLC_FOURCC('b','m','p',' ');
 474         }
 475         else if( ( !strcmp( p_attach->psz_mime, "image/x-portable-anymap" ) )  || /* PNM */
 476                  ( !strcmp( p_attach->psz_mime, "image/x-portable-bitmap" ) )  || /* PBM */
 477                  ( !strcmp( p_attach->psz_mime, "image/x-portable-graymap" ) ) || /* PGM */
 478                  ( !strcmp( p_attach->psz_mime, "image/x-portable-pixmap" ) ) )   /* PPM */
 479         {
 480             type = VLC_FOURCC('p','n','m',' ');
 481         }
 482         else if ( !strcmp( p_attach->psz_mime, "image/gif" ) )         /* GIF */
 483             type = VLC_FOURCC('g','i','f',' ');
 484         else if ( !strcmp( p_attach->psz_mime, "image/jpeg" ) )        /* JPG, JPEG */
 485             type = VLC_FOURCC('j','p','e','g');
 486         else if ( !strcmp( p_attach->psz_mime, "image/pcx" ) )         /* PCX */
 487             type = VLC_FOURCC('p','c','x',' ');
 488         else if ( !strcmp( p_attach->psz_mime, "image/png" ) )         /* PNG */
 489             type = VLC_FOURCC('p','n','g',' ');
 490         else if ( !strcmp( p_attach->psz_mime, "image/tiff" ) )        /* TIF, TIFF */
 491             type = VLC_FOURCC('t','i','f','f');
 492         else if ( !strcmp( p_attach->psz_mime, "image/x-tga" ) )       /* TGA */
 493             type = VLC_FOURCC('t','g','a',' ');
 494         else if ( !strcmp( p_attach->psz_mime, "image/x-xpixmap") )    /* XPM */
 495             type = VLC_FOURCC('x','p','m',' ');
 496
 497         if( ( type != 0 ) &&
 498             ( p_attach->i_data > 0 ) &&
 499             ( p_attach->p_data != NULL ) )
 500         {
 501             picture_t         *p_pic = NULL;
 502             image_handler_t   *p_image;
 503
 504             p_image = image_HandlerCreate( p_dec );
 505             if( p_image != NULL )
 506             {
 507                 block_t   *p_block;
 508
 509                 p_block = block_New( p_image->p_parent, p_attach->i_data );
 510
 511                 if( p_block != NULL )
 512                 {
 513                     video_format_t     fmt_in;
 514                     video_format_t     fmt_out;
 515
 516                     memcpy( p_block->p_buffer, p_attach->p_data, p_attach->i_data );
 517
 518                     memset( &fmt_in,  0, sizeof( video_format_t));
 519                     memset( &fmt_out, 0, sizeof( video_format_t));
 520
 521                     fmt_in.i_chroma  = type;
 522                     fmt_out.i_chroma = VLC_FOURCC('Y','U','V','A');
 523
 524                     /* Find a suitable decoder module */
 525                     if( module_Exists( p_dec, "sdl_image" ) )
 526                     {
 527                         /* ffmpeg thinks it can handle bmp properly but it can't (at least
 528                          * not all of them), so use sdl_image if it is available */
 529
 530                         vlc_value_t val;
 531
 532                         var_Create( p_dec, "codec", VLC_VAR_MODULE | VLC_VAR_DOINHERIT );
 533                         val.psz_string = (char*) "sdl_image";
 534                         var_Set( p_dec, "codec", val );
 535                     }
 536
 537                     p_pic = image_Read( p_image, p_block, &fmt_in, &fmt_out );
 538                     var_Destroy( p_dec, "codec" );
 539                 }
 540
 541                 image_HandlerDelete( p_image );
 542             }
 543             if( p_pic )
 544             {
 545                 image_attach_t *p_picture = malloc( sizeof(image_attach_t) );
 546
 547                 if( p_picture )
 548                 {
 549                     p_picture->psz_filename = strdup( p_attach->psz_name );
 550                     p_picture->p_pic = p_pic;
 551
 552                     TAB_APPEND( p_sys->i_images, p_sys->pp_images, p_picture );
 553                 }
 554             }
 555         }
 556         vlc_input_attachment_Delete( pp_attachments[ k ] );
 557     }
 558     free( pp_attachments );
 559
 560     return VLC_SUCCESS;
 561 }
 562
 563 static void ParseUSFHeaderTags( decoder_t *p_dec, xml_reader_t *p_xml_reader )
 564 {
 565     decoder_sys_t *p_sys = p_dec->p_sys;
 566     char *psz_node;
 567     ssa_style_t *p_style = NULL;
 568     int i_style_level = 0;
 569     int i_metadata_level = 0;
 570
 571     while ( xml_ReaderRead( p_xml_reader ) == 1 )
 572     {
 573         switch ( xml_ReaderNodeType( p_xml_reader ) )
 574         {
 575             case XML_READER_TEXT:
 576             case XML_READER_NONE:
 577                 break;
 578             case XML_READER_ENDELEM:
 579                 psz_node = xml_ReaderName( p_xml_reader );
 580
 581                 if( !psz_node )
 582                     break;
 583                 switch (i_style_level)
 584                 {
 585                     case 0:
 586                         if( !strcasecmp( "metadata", psz_node ) && (i_metadata_level == 1) )
 587                         {
 588                             i_metadata_level--;
 589                         }
 590                         break;
 591                     case 1:
 592                         if( !strcasecmp( "styles", psz_node ) )
 593                         {
 594                             i_style_level--;
 595                         }
 596                         break;
 597                     case 2:
 598                         if( !strcasecmp( "style", psz_node ) )
 599                         {
 600                             TAB_APPEND( p_sys->i_ssa_styles, p_sys->pp_ssa_styles, p_style );
 601
 602                             p_style = NULL;
 603                             i_style_level--;
 604                         }
 605                         break;
 606                 }
 607
 608                 free( psz_node );
 609                 break;
 610             case XML_READER_STARTELEM:
 611                 psz_node = xml_ReaderName( p_xml_reader );
 612
 613                 if( !psz_node )
 614                     break;
 615
 616                 if( !strcasecmp( "metadata", psz_node ) && (i_style_level == 0) )
 617                 {
 618                     i_metadata_level++;
 619                 }
 620                 else if( !strcasecmp( "resolution", psz_node ) &&
 621                          ( i_metadata_level == 1) )
 622                 {
 623                     while ( xml_ReaderNextAttr( p_xml_reader ) == VLC_SUCCESS )
 624                     {
 625                         char *psz_name = xml_ReaderName ( p_xml_reader );
 626                         char *psz_value = xml_ReaderValue ( p_xml_reader );
 627
 628                         if( psz_name && psz_value )
 629                         {
 630                             if( !strcasecmp( "x", psz_name ) )
 631                                 p_sys->i_original_width = atoi( psz_value );
 632                             else if( !strcasecmp( "y", psz_name ) )
 633                                 p_sys->i_original_height = atoi( psz_value );
 634                         }
 635                         if( psz_name )  free( psz_name );
 636                         if( psz_value ) free( psz_value );
 637                     }
 638                 }
 639                 else if( !strcasecmp( "styles", psz_node ) && (i_style_level == 0) )
 640                 {
 641                     i_style_level++;
 642                 }
 643                 else if( !strcasecmp( "style", psz_node ) && (i_style_level == 1) )
 644                 {
 645                     i_style_level++;
 646
 647                     p_style = calloc( 1, sizeof(ssa_style_t) );
 648                     if( ! p_style )
 649                     {
 650                         msg_Err( p_dec, "out of memory" );
 651                         free( psz_node );
 652                         break;
 653                     }
 654                     /* All styles are supposed to default to Default, and then
 655                      * one or more settings are over-ridden.
 656                      * At the moment this only effects styles defined AFTER
 657                      * Default in the XML
 658                      */
 659                     int i;
 660                     for( i = 0; i < p_sys->i_ssa_styles; i++ )
 661                     {
 662                         if( !strcasecmp( p_sys->pp_ssa_styles[i]->psz_stylename, "Default" ) )
 663                         {
 664                             ssa_style_t *p_default_style = p_sys->pp_ssa_styles[i];
 665
 666                             memcpy( p_style, p_default_style, sizeof( ssa_style_t ) );
 667                             p_style->font_style.psz_fontname = strdup( p_style->font_style.psz_fontname );
 668                             p_style->psz_stylename = NULL;
 669                         }
 670                     }
 671
 672                     while ( xml_ReaderNextAttr( p_xml_reader ) == VLC_SUCCESS )
 673                     {
 674                         char *psz_name = xml_ReaderName ( p_xml_reader );
 675                         char *psz_value = xml_ReaderValue ( p_xml_reader );
 676
 677                         if( psz_name && psz_value )
 678                         {
 679                             if( !strcasecmp( "name", psz_name ) )
 680                                 p_style->psz_stylename = strdup( psz_value);
 681                         }
 682                         if( psz_name )  free( psz_name );
 683                         if( psz_value ) free( psz_value );
 684                     }
 685                 }
 686                 else if( !strcasecmp( "fontstyle", psz_node ) && (i_style_level == 2) )
 687                 {
 688                     while ( xml_ReaderNextAttr( p_xml_reader ) == VLC_SUCCESS )
 689                     {
 690                         char *psz_name = xml_ReaderName ( p_xml_reader );
 691                         char *psz_value = xml_ReaderValue ( p_xml_reader );
 692
 693                         if( psz_name && psz_value )
 694                         {
 695                             if( !strcasecmp( "face", psz_name ) )
 696                             {
 697                                 if( p_style->font_style.psz_fontname )
 698                                     free( p_style->font_style.psz_fontname );
 699                                 p_style->font_style.psz_fontname = strdup( psz_value );
 700                             }
 701                             else if( !strcasecmp( "size", psz_name ) )
 702                             {
 703                                 if( ( *psz_value == '+' ) || ( *psz_value == '-' ) )
 704                                 {
 705                                     int i_value = atoi( psz_value );
 706
 707                                     if( ( i_value >= -5 ) && ( i_value <= 5 ) )
 708                                         p_style->font_style.i_font_size  +=
 709                                             ( i_value * p_style->font_style.i_font_size ) / 10;
 710                                     else if( i_value < -5 )
 711                                         p_style->font_style.i_font_size  = - i_value;
 712                                     else if( i_value > 5 )
 713                                         p_style->font_style.i_font_size  = i_value;
 714                                 }
 715                                 else
 716                                     p_style->font_style.i_font_size  = atoi( psz_value );
 717                             }
 718                             else if( !strcasecmp( "italic", psz_name ) )
 719                             {
 720                                 if( !strcasecmp( "yes", psz_value ))
 721                                     p_style->font_style.i_style_flags |= STYLE_ITALIC;
 722                                 else
 723                                     p_style->font_style.i_style_flags &= ~STYLE_ITALIC;
 724                             }
 725                             else if( !strcasecmp( "weight", psz_name ) )
 726                             {
 727                                 if( !strcasecmp( "bold", psz_value ))
 728                                     p_style->font_style.i_style_flags |= STYLE_BOLD;
 729                                 else
 730                                     p_style->font_style.i_style_flags &= ~STYLE_BOLD;
 731                             }
 732                             else if( !strcasecmp( "underline", psz_name ) )
 733                             {
 734                                 if( !strcasecmp( "yes", psz_value ))
 735                                     p_style->font_style.i_style_flags |= STYLE_UNDERLINE;
 736                                 else
 737                                     p_style->font_style.i_style_flags &= ~STYLE_UNDERLINE;
 738                             }
 739                             else if( !strcasecmp( "color", psz_name ) )
 740                             {
 741                                 if( *psz_value == '#' )
 742                                 {
 743                                     unsigned long col = strtol(psz_value+1, NULL, 16);
 744                                     p_style->font_style.i_font_color = (col & 0x00ffffff);
 745                                     p_style->font_style.i_font_alpha = (col >> 24) & 0xff;
 746                                 }
 747                             }
 748                             else if( !strcasecmp( "outline-color", psz_name ) )
 749                             {
 750                                 if( *psz_value == '#' )
 751                                 {
 752                                     unsigned long col = strtol(psz_value+1, NULL, 16);
 753                                     p_style->font_style.i_outline_color = (col & 0x00ffffff);
 754                                     p_style->font_style.i_outline_alpha = (col >> 24) & 0xff;
 755                                 }
 756                             }
 757                             else if( !strcasecmp( "outline-level", psz_name ) )
 758                             {
 759                                 p_style->font_style.i_outline_width = atoi( psz_value );
 760                             }
 761                             else if( !strcasecmp( "shadow-color", psz_name ) )
 762                             {
 763                                 if( *psz_value == '#' )
 764                                 {
 765                                     unsigned long col = strtol(psz_value+1, NULL, 16);
 766                                     p_style->font_style.i_shadow_color = (col & 0x00ffffff);
 767                                     p_style->font_style.i_shadow_alpha = (col >> 24) & 0xff;
 768                                 }
 769                             }
 770                             else if( !strcasecmp( "shadow-level", psz_name ) )
 771                             {
 772                                 p_style->font_style.i_shadow_width = atoi( psz_value );
 773                             }
 774                             else if( !strcasecmp( "back-color", psz_name ) )
 775                             {
 776                                 if( *psz_value == '#' )
 777                                 {
 778                                     unsigned long col = strtol(psz_value+1, NULL, 16);
 779                                     p_style->font_style.i_karaoke_background_color = (col & 0x00ffffff);
 780                                     p_style->font_style.i_karaoke_background_alpha = (col >> 24) & 0xff;
 781                                 }
 782                             }
 783                             else if( !strcasecmp( "spacing", psz_name ) )
 784                             {
 785                                 p_style->font_style.i_spacing = atoi( psz_value );
 786                             }
 787                         }
 788                         if( psz_name )  free( psz_name );
 789                         if( psz_value ) free( psz_value );
 790                     }
 791                 }
 792                 else if( !strcasecmp( "position", psz_node ) && (i_style_level == 2) )
 793                 {
 794                     while ( xml_ReaderNextAttr( p_xml_reader ) == VLC_SUCCESS )
 795                     {
 796                         char *psz_name = xml_ReaderName ( p_xml_reader );
 797                         char *psz_value = xml_ReaderValue ( p_xml_reader );
 798
 799                         if( psz_name && psz_value )
 800                         {
 801                             if( !strcasecmp( "alignment", psz_name ) )
 802                             {
 803                                 if( !strcasecmp( "TopLeft", psz_value ) )
 804                                     p_style->i_align = SUBPICTURE_ALIGN_TOP | SUBPICTURE_ALIGN_LEFT;
 805                                 else if( !strcasecmp( "TopCenter", psz_value ) )
 806                                     p_style->i_align = SUBPICTURE_ALIGN_TOP;
 807                                 else if( !strcasecmp( "TopRight", psz_value ) )
 808                                     p_style->i_align = SUBPICTURE_ALIGN_TOP | SUBPICTURE_ALIGN_RIGHT;
 809                                 else if( !strcasecmp( "MiddleLeft", psz_value ) )
 810                                     p_style->i_align = SUBPICTURE_ALIGN_LEFT;
 811                                 else if( !strcasecmp( "MiddleCenter", psz_value ) )
 812                                     p_style->i_align = 0;
 813                                 else if( !strcasecmp( "MiddleRight", psz_value ) )
 814                                     p_style->i_align = SUBPICTURE_ALIGN_RIGHT;
 815                                 else if( !strcasecmp( "BottomLeft", psz_value ) )
 816                                     p_style->i_align = SUBPICTURE_ALIGN_BOTTOM | SUBPICTURE_ALIGN_LEFT;
 817                                 else if( !strcasecmp( "BottomCenter", psz_value ) )
 818                                     p_style->i_align = SUBPICTURE_ALIGN_BOTTOM;
 819                                 else if( !strcasecmp( "BottomRight", psz_value ) )
 820                                     p_style->i_align = SUBPICTURE_ALIGN_BOTTOM | SUBPICTURE_ALIGN_RIGHT;
 821                             }
 822                             else if( !strcasecmp( "horizontal-margin", psz_name ) )
 823                             {
 824                                 if( strchr( psz_value, '%' ) )
 825                                 {
 826                                     p_style->i_margin_h = 0;
 827                                     p_style->i_margin_percent_h = atoi( psz_value );
 828                                 }
 829                                 else
 830                                 {
 831                                     p_style->i_margin_h = atoi( psz_value );
 832                                     p_style->i_margin_percent_h = 0;
 833                                 }
 834                             }
 835                             else if( !strcasecmp( "vertical-margin", psz_name ) )
 836                             {
 837                                 if( strchr( psz_value, '%' ) )
 838                                 {
 839                                     p_style->i_margin_v = 0;
 840                                     p_style->i_margin_percent_v = atoi( psz_value );
 841                                 }
 842                                 else
 843                                 {
 844                                     p_style->i_margin_v = atoi( psz_value );
 845                                     p_style->i_margin_percent_v = 0;
 846                                 }
 847                             }
 848                         }
 849                         if( psz_name )  free( psz_name );
 850                         if( psz_value ) free( psz_value );
 851                     }
 852                 }
 853
 854                 free( psz_node );
 855                 break;
 856         }
 857     }
 858     if( p_style ) free( p_style );
 859 }
 860
 861
 862
 863 static subpicture_region_t *ParseUSFString( decoder_t *p_dec,
 864                                             char *psz_subtitle,
 865                                             subpicture_t *p_spu_in )
 866 {
 867     decoder_sys_t        *p_sys = p_dec->p_sys;
 868     subpicture_t         *p_spu = p_spu_in;
 869     subpicture_region_t  *p_region_first = NULL;
 870     subpicture_region_t  *p_region_upto  = p_region_first;
 871
 872     while( *psz_subtitle )
 873     {
 874         if( *psz_subtitle == '<' )
 875         {
 876             char *psz_end = NULL;
 877
 878             if(( !strncasecmp( psz_subtitle, "<text ", 6 )) ||
 879                ( !strncasecmp( psz_subtitle, "<text>", 6 )))
 880             {
 881                 psz_end = strcasestr( psz_subtitle, "</text>" );
 882
 883                 if( psz_end )
 884                 {
 885                     subpicture_region_t  *p_text_region;
 886
 887                     psz_end += strcspn( psz_end, ">" ) + 1;
 888
 889                     p_text_region = CreateTextRegion( p_dec,
 890                                                       p_spu,
 891                                                       psz_subtitle,
 892                                                       psz_end - psz_subtitle,
 893                                                       p_sys->i_align );
 894
 895                     if( p_text_region )
 896                     {
 897                         p_text_region->psz_text = CreatePlainText( p_text_region->psz_html );
 898
 899                         if( ! var_CreateGetBool( p_dec, "subsdec-formatted" ) )
 900                         {
 901                             free( p_text_region->psz_html );
 902                             p_text_region->psz_html = NULL;
 903                         }
 904                     }
 905
 906                     if( !p_region_first )
 907                     {
 908                         p_region_first = p_region_upto = p_text_region;
 909                     }
 910                     else if( p_text_region )
 911                     {
 912                         p_region_upto->p_next = p_text_region;
 913                         p_region_upto = p_region_upto->p_next;
 914                     }
 915                 }
 916             }
 917             else if(( !strncasecmp( psz_subtitle, "<karaoke ", 9 )) ||
 918                     ( !strncasecmp( psz_subtitle, "<karaoke>", 9 )))
 919             {
 920                 psz_end = strcasestr( psz_subtitle, "</karaoke>" );
 921
 922                 if( psz_end )
 923                 {
 924                     subpicture_region_t  *p_text_region;
 925
 926                     psz_end += strcspn( psz_end, ">" ) + 1;
 927
 928                     p_text_region = CreateTextRegion( p_dec,
 929                                                       p_spu,
 930                                                       psz_subtitle,
 931                                                       psz_end - psz_subtitle,
 932                                                       p_sys->i_align );
 933
 934                     if( p_text_region )
 935                     {
 936                         if( ! var_CreateGetBool( p_dec, "subsdec-formatted" ) )
 937                         {
 938                             free( p_text_region->psz_html );
 939                             p_text_region->psz_html = NULL;
 940                         }
 941                     }
 942                     if( !p_region_first )
 943                     {
 944                         p_region_first = p_region_upto = p_text_region;
 945                     }
 946                     else if( p_text_region )
 947                     {
 948                         p_region_upto->p_next = p_text_region;
 949                         p_region_upto = p_region_upto->p_next;
 950                     }
 951                 }
 952             }
 953             else if(( !strncasecmp( psz_subtitle, "<image ", 7 )) ||
 954                     ( !strncasecmp( psz_subtitle, "<image>", 7 )))
 955             {
 956                 subpicture_region_t *p_image_region = NULL;
 957
 958                 char *psz_end = strcasestr( psz_subtitle, "</image>" );
 959                 char *psz_content = strchr( psz_subtitle, '>' );
 960                 int   i_transparent = -1;
 961
 962                 /* If a colorkey parameter is specified, then we have to map
 963                  * that index in the picture through as transparent (it is
 964                  * required by the USF spec but is also recommended that if the
 965                  * creator really wants a transparent colour that they use a
 966                  * type like PNG that properly supports it; this goes doubly
 967                  * for VLC because the pictures are stored internally in YUV
 968                  * and the resulting colour-matching may not produce the
 969                  * desired results.)
 970                  */
 971                 char *psz_tmp = GrabAttributeValue( "colorkey", psz_subtitle );
 972                 if( psz_tmp )
 973                 {
 974                     if( *psz_tmp == '#' )
 975                         i_transparent = strtol( psz_tmp + 1, NULL, 16 ) & 0x00ffffff;
 976                     free( psz_tmp );
 977                 }
 978                 if( psz_content && ( psz_content < psz_end ) )
 979                 {
 980                     char *psz_filename = strndup( &psz_content[1], psz_end - &psz_content[1] );
 981                     if( psz_filename )
 982                     {
 983                         p_image_region = LoadEmbeddedImage( p_dec, p_spu,
 984                                             psz_filename, i_transparent );
 985                         free( psz_filename );
 986                     }
 987                 }
 988
 989                 if( psz_end ) psz_end += strcspn( psz_end, ">" ) + 1;
 990
 991                 if( p_image_region )
 992                 {
 993                     SetupPositions( p_image_region, psz_subtitle );
 994
 995                     p_image_region->p_next   = NULL;
 996                     p_image_region->psz_text = NULL;
 997                     p_image_region->psz_html = NULL;
 998
 999                 }
1000                 if( !p_region_first )
1001                 {
1002                     p_region_first = p_region_upto = p_image_region;
1003                 }
1004                 else if( p_image_region )
1005                 {
1006                     p_region_upto->p_next = p_image_region;
1007                     p_region_upto = p_region_upto->p_next;
1008                 }
1009             }
1010             if( psz_end )
1011                 psz_subtitle = psz_end - 1;
1012
1013             psz_subtitle += strcspn( psz_subtitle, ">" );
1014         }
1015
1016         psz_subtitle++;
1017     }
1018
1019     return p_region_first;
1020 }
1021
1022 /*****************************************************************************
1023  * ParseUSFHeader: Retrieve global formatting information etc
1024  *****************************************************************************/
1025 static void ParseUSFHeader( decoder_t *p_dec )
1026 {
1027     stream_t      *p_sub = NULL;
1028     xml_t         *p_xml = NULL;
1029     xml_reader_t  *p_xml_reader = NULL;
1030
1031     p_sub = stream_MemoryNew( VLC_OBJECT(p_dec),
1032                               p_dec->fmt_in.p_extra,
1033                               p_dec->fmt_in.i_extra,
1034                               VLC_TRUE );
1035     if( !p_sub )
1036         return;
1037
1038     p_xml = xml_Create( p_dec );
1039     if( p_xml )
1040     {
1041         p_xml_reader = xml_ReaderCreate( p_xml, p_sub );
1042         if( p_xml_reader )
1043         {
1044             /* Look for Root Node */
1045             if( xml_ReaderRead( p_xml_reader ) == 1 )
1046             {
1047                 char *psz_node = xml_ReaderName( p_xml_reader );
1048
1049                 if( !strcasecmp( "usfsubtitles", psz_node ) )
1050                     ParseUSFHeaderTags( p_dec, p_xml_reader );
1051
1052                 free( psz_node );
1053             }
1054
1055             xml_ReaderDelete( p_xml, p_xml_reader );
1056         }
1057         xml_Delete( p_xml );
1058     }
1059     stream_Delete( p_sub );
1060 }
1061
1062 /* Function now handles tags which has attribute values, and tries
1063  * to deal with &' commands too. It no longer modifies the string
1064  * in place, so that the original text can be reused
1065  */
1066 static char *StripTags( char *psz_subtitle )
1067 {
1068     char *psz_text_start;
1069     char *psz_text;
1070
1071     psz_text = psz_text_start = malloc( strlen( psz_subtitle ) + 1 );
1072     if( !psz_text_start )
1073         return NULL;
1074
1075     while( *psz_subtitle )
1076     {
1077         /* Mask out any pre-existing LFs in the subtitle */
1078         if( *psz_subtitle == '\n' )
1079             *psz_subtitle = ' ';
1080
1081         if( *psz_subtitle == '<' )
1082         {
1083             if( strncasecmp( psz_subtitle, "<br/>", 5 ) == 0 )
1084                 *psz_text++ = '\n';
1085
1086             psz_subtitle += strcspn( psz_subtitle, ">" );
1087         }
1088         else if( *psz_subtitle == '&' )
1089         {
1090             if( !strncasecmp( psz_subtitle, "&lt;", 4 ))
1091             {
1092                 *psz_text++ = '<';
1093                 psz_subtitle += strcspn( psz_subtitle, ";" );
1094             }
1095             else if( !strncasecmp( psz_subtitle, "&gt;", 4 ))
1096             {
1097                 *psz_text++ = '>';
1098                 psz_subtitle += strcspn( psz_subtitle, ";" );
1099             }
1100             else if( !strncasecmp( psz_subtitle, "&amp;", 5 ))
1101             {
1102                 *psz_text++ = '&';
1103                 psz_subtitle += strcspn( psz_subtitle, ";" );
1104             }
1105             else if( !strncasecmp( psz_subtitle, "&quot;", 6 ))
1106             {
1107                 *psz_text++ = '\"';
1108                 psz_subtitle += strcspn( psz_subtitle, ";" );
1109             }
1110             else
1111             {
1112                 /* Assume it is just a normal ampersand */
1113                 *psz_text++ = '&';
1114             }
1115         }
1116         else
1117         {
1118             *psz_text++ = *psz_subtitle;
1119         }
1120
1121         psz_subtitle++;
1122     }
1123     *psz_text = '\0';
1124     psz_text_start = realloc( psz_text_start, strlen( psz_text_start ) + 1 );
1125
1126     return psz_text_start;
1127 }
1128
1129 /* Turn a HTML subtitle, turn into a plain-text version,
1130  *  complete with sensible whitespace compaction
1131  */
1132
1133 static char *CreatePlainText( char *psz_subtitle )
1134 {
1135     char *psz_text = StripTags( psz_subtitle );
1136     char *s;
1137
1138     if( !psz_text )
1139         return NULL;
1140
1141     s = strpbrk( psz_text, "\t\r\n " );
1142     while( s )
1143     {
1144         int   k;
1145         char  spc = ' ';
1146         int   i_whitespace = strspn( s, "\t\r\n " );
1147
1148         /* Favour '\n' over other whitespaces - if one of these
1149          * occurs in the whitespace use a '\n' as our value,
1150          * otherwise just use a ' '
1151          */
1152         for( k = 0; k < i_whitespace; k++ )
1153             if( s[k] == '\n' ) spc = '\n';
1154
1155         if( i_whitespace > 1 )
1156         {
1157             memmove( &s[1],
1158                      &s[i_whitespace],
1159                      strlen( s ) - i_whitespace + 1 );
1160         }
1161         *s++ = spc;
1162
1163         s = strpbrk( s, "\t\r\n " );
1164     }
1165     return psz_text;
1166 }
1167
1168 /****************************************************************************
1169  * download and resize image located at psz_url
1170  ***************************************************************************/
1171 static subpicture_region_t *LoadEmbeddedImage( decoder_t *p_dec,
1172                                                subpicture_t *p_spu,
1173                                                const char *psz_filename,
1174                                                int i_transparent_color )
1175 {
1176     decoder_sys_t         *p_sys = p_dec->p_sys;
1177     subpicture_region_t   *p_region;
1178     video_format_t         fmt_out;
1179     int                    k;
1180     picture_t             *p_pic = NULL;
1181
1182     for( k = 0; k < p_sys->i_images; k++ )
1183     {
1184         if( p_sys->pp_images &&
1185             !strcmp( p_sys->pp_images[k]->psz_filename, psz_filename ) )
1186         {
1187             p_pic = p_sys->pp_images[k]->p_pic;
1188             break;
1189         }
1190     }
1191
1192     if( !p_pic )
1193     {
1194         msg_Err( p_dec, "Unable to read image %s", psz_filename );
1195         return NULL;
1196     }
1197
1198     /* Display the feed's image */
1199     memset( &fmt_out, 0, sizeof( video_format_t));
1200
1201     fmt_out.i_chroma = VLC_FOURCC('Y','U','V','A');
1202     fmt_out.i_aspect = VOUT_ASPECT_FACTOR;
1203     fmt_out.i_sar_num = fmt_out.i_sar_den = 1;
1204     fmt_out.i_width =
1205         fmt_out.i_visible_width = p_pic->p[Y_PLANE].i_visible_pitch;
1206     fmt_out.i_height =
1207         fmt_out.i_visible_height = p_pic->p[Y_PLANE].i_visible_lines;
1208
1209     p_region = p_spu->pf_create_region( VLC_OBJECT(p_dec), &fmt_out );
1210     if( !p_region )
1211     {
1212         msg_Err( p_dec, "cannot allocate SPU region" );
1213         return NULL;
1214     }
1215     vout_CopyPicture( p_dec, &p_region->picture, p_pic );
1216
1217     /* This isn't the best way to do this - if you really want transparency, then
1218      * you're much better off using an image type that supports it like PNG. The
1219      * spec requires this support though.
1220      */
1221     if( i_transparent_color > 0 )
1222     {
1223         uint8_t i_r = ( i_transparent_color >> 16 ) & 0xff;
1224         uint8_t i_g = ( i_transparent_color >>  8 ) & 0xff;
1225         uint8_t i_b = ( i_transparent_color       ) & 0xff;
1226         uint8_t i_y = ( ( (  66 * i_r + 129 * i_g +  25 * i_b + 128 ) >> 8 ) + 16 );
1227         uint8_t i_u =   ( ( -38 * i_r -  74 * i_g + 112 * i_b + 128 ) >> 8 ) + 128 ;
1228         uint8_t i_v =   ( ( 112 * i_r -  94 * i_g -  18 * i_b + 128 ) >> 8 ) + 128 ;
1229
1230         if( ( p_region->picture.Y_PITCH == p_region->picture.U_PITCH ) &&
1231             ( p_region->picture.Y_PITCH == p_region->picture.V_PITCH ) &&
1232             ( p_region->picture.Y_PITCH == p_region->picture.A_PITCH ) )
1233         {
1234             int i_lines = p_region->picture.p[ Y_PLANE ].i_lines;
1235             if( i_lines > p_region->picture.p[ U_PLANE ].i_lines )
1236                 i_lines = p_region->picture.p[ U_PLANE ].i_lines;
1237             if( i_lines > p_region->picture.p[ V_PLANE ].i_lines )
1238                 i_lines = p_region->picture.p[ V_PLANE ].i_lines;
1239             if( i_lines > p_region->picture.p[ A_PLANE ].i_lines )
1240                 i_lines = p_region->picture.p[ A_PLANE ].i_lines;
1241
1242             int   i;
1243
1244             for( i = 0; i < p_region->picture.A_PITCH * i_lines; i++ )
1245             {
1246                 if(( p_region->picture.Y_PIXELS[ i ] == i_y ) &&
1247                    ( p_region->picture.U_PIXELS[ i ] == i_u ) &&
1248                    ( p_region->picture.V_PIXELS[ i ] == i_v ) )
1249                 {
1250                     p_region->picture.A_PIXELS[ i ] = 1;
1251                 }
1252             }
1253         }
1254     }
1255     return p_region;
1256 }