modules/codec/substx3g.c

   1 /*****************************************************************************
   2  * substx3gsub.c : MP4 tx3g subtitles decoder
   3  *****************************************************************************
   4  * Copyright (C) 2014 VLC authors and VideoLAN
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation, Inc.,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <vlc_common.h>
  26 #include <vlc_plugin.h>
  27 #include <vlc_codec.h>
  28 #include <vlc_sout.h>
  29 #include <vlc_charset.h>
  30
  31 #include "substext.h"
  32 #include "../demux/mp4/minibox.h"
  33
  34 /*****************************************************************************
  35  * Module descriptor.
  36  *****************************************************************************/
  37 static int OpenDecoder ( vlc_object_t * );
  38 static void CloseDecoder ( vlc_object_t * );
  39 static int Decode( decoder_t *, block_t * );
  40 #ifdef ENABLE_SOUT
  41 static int OpenEncoder ( vlc_object_t * );
  42 static block_t * Encode( encoder_t *, subpicture_t * );
  43 #endif
  44
  45 vlc_module_begin ()
  46     set_description( N_("tx3g subtitles decoder") )
  47     set_shortname( N_("tx3g subtitles") )
  48     set_capability( "spu decoder", 100 )
  49     set_category( CAT_INPUT )
  50     set_subcategory( SUBCAT_INPUT_SCODEC )
  51     set_callbacks( OpenDecoder, CloseDecoder )
  52 #ifdef ENABLE_SOUT
  53     add_submodule ()
  54         set_description( N_("tx3g subtitles encoder") )
  55         set_shortname( N_("tx3g subtitles encoder") )
  56         set_capability( "encoder", 101 )
  57         set_callbacks( OpenEncoder, NULL )
  58 #endif
  59 vlc_module_end ()
  60
  61 /****************************************************************************
  62  * Local structs
  63  ****************************************************************************/
  64
  65 /*****************************************************************************
  66  * Local:
  67  *****************************************************************************/
  68
  69 #define FONT_FACE_BOLD      0x1
  70 #define FONT_FACE_ITALIC    0x2
  71 #define FONT_FACE_UNDERLINE 0x4
  72
  73 static int ConvertToVLCFlags( int i_atomflags )
  74 {
  75     int i_vlcstyles_flags = 0;
  76     if ( i_atomflags & FONT_FACE_BOLD )
  77         i_vlcstyles_flags |= STYLE_BOLD;
  78     if ( i_atomflags & FONT_FACE_ITALIC )
  79         i_vlcstyles_flags |= STYLE_ITALIC;
  80     if ( i_atomflags & FONT_FACE_UNDERLINE )
  81         i_vlcstyles_flags |= STYLE_UNDERLINE;
  82     return i_vlcstyles_flags;
  83 }
  84
  85 static size_t str8len( const char *psz_string )
  86 {
  87     const char *psz_tmp = psz_string;
  88     size_t i=0;
  89     while ( *psz_tmp )
  90     {
  91         if ( (*psz_tmp & 0xC0) != 0x80 ) i++;
  92         psz_tmp++;
  93     }
  94     return i;
  95 }
  96
  97 static char * str8indup( const char *psz_string, size_t i_skip, size_t n )
  98 {
  99     while( i_skip && *psz_string )
 100     {
 101         if ( (*psz_string & 0xC0) != 0x80 ) i_skip--;
 102         psz_string++;
 103     }
 104     if ( ! *psz_string || i_skip ) return NULL;
 105
 106     const char *psz_tmp = psz_string;
 107     while( n && *psz_tmp )
 108     {
 109         if ( (*psz_tmp & 0xC0) != 0x80 ) n--;
 110         psz_tmp++;
 111     }
 112     return strndup( psz_string, psz_tmp - psz_string );
 113 }
 114
 115 typedef struct tx3g_segment_t tx3g_segment_t;
 116
 117 struct tx3g_segment_t
 118 {
 119     text_segment_t *s;
 120     size_t i_size;
 121     tx3g_segment_t *p_next3g;
 122 };
 123
 124 static tx3g_segment_t * tx3g_segment_New( const char *psz_string )
 125 {
 126     tx3g_segment_t *p_seg = malloc( sizeof(tx3g_segment_t) );
 127     if( p_seg )
 128     {
 129         p_seg->i_size = 0;
 130         p_seg->p_next3g = NULL;
 131         p_seg->s = text_segment_New( psz_string );
 132         if( !p_seg->s )
 133         {
 134             free( p_seg );
 135             p_seg = NULL;
 136         }
 137     }
 138     return p_seg;
 139 }
 140
 141 static void SegmentDoSplit( tx3g_segment_t *p_segment, uint16_t i_start, uint16_t i_end,
 142                             tx3g_segment_t **pp_segment_left,
 143                             tx3g_segment_t **pp_segment_middle,
 144                             tx3g_segment_t **pp_segment_right )
 145 {
 146     tx3g_segment_t *p_segment_left = NULL, *p_segment_right = NULL, *p_segment_middle = NULL;
 147
 148     if ( (p_segment->i_size - i_start < 1) || (p_segment->i_size - i_end < 1) )
 149         goto error;
 150
 151     if ( i_start > 0 )
 152     {
 153         char* psz_text = str8indup( p_segment->s->psz_text, 0, i_start );
 154         p_segment_left = tx3g_segment_New( psz_text );
 155         free( psz_text );
 156         if ( !p_segment_left ) goto error;
 157         p_segment_left->s->style = text_style_Duplicate( p_segment->s->style );
 158         p_segment_left->i_size = str8len( p_segment_left->s->psz_text );
 159     }
 160
 161     char* psz_midtext = str8indup( p_segment->s->psz_text, i_start, i_end - i_start + 1 );
 162     p_segment_middle = tx3g_segment_New( psz_midtext );
 163     free( psz_midtext );
 164     if ( !p_segment_middle ) goto error;
 165     p_segment_middle->s->style = text_style_Duplicate( p_segment->s->style );
 166     p_segment_middle->i_size = str8len( p_segment_middle->s->psz_text );
 167
 168     if ( i_end < (p_segment->i_size - 1) )
 169     {
 170         char* psz_text = str8indup( p_segment->s->psz_text, i_end + 1, p_segment->i_size - i_end - 1 );
 171         p_segment_right = tx3g_segment_New( psz_text );
 172         free( psz_text );
 173         if ( !p_segment_right ) goto error;
 174         p_segment_right->s->style = text_style_Duplicate( p_segment->s->style );
 175         p_segment_right->i_size = str8len( p_segment_right->s->psz_text );
 176     }
 177
 178     if ( p_segment_left ) p_segment_left->p_next3g = p_segment_middle;
 179     if ( p_segment_right ) p_segment_middle->p_next3g = p_segment_right;
 180
 181     *pp_segment_left = p_segment_left;
 182     *pp_segment_middle = p_segment_middle;
 183     *pp_segment_right = p_segment_right;
 184
 185     return;
 186
 187 error:
 188     if( p_segment_middle )
 189     {
 190         text_segment_Delete( p_segment_middle->s );
 191         free( p_segment_middle );
 192     }
 193     if( p_segment_left )
 194     {
 195         text_segment_Delete( p_segment_left->s );
 196         free( p_segment_left );
 197     }
 198     *pp_segment_left = *pp_segment_middle = *pp_segment_right = NULL;
 199 }
 200
 201 static bool SegmentSplit( tx3g_segment_t *p_prev, tx3g_segment_t **pp_segment,
 202                           const uint16_t i_start, const uint16_t i_end,
 203                           const text_style_t *p_styles )
 204 {
 205     tx3g_segment_t *p_segment_left = NULL, *p_segment_middle = NULL, *p_segment_right = NULL;
 206
 207     if ( (*pp_segment)->i_size == 0 ) return false;
 208     if ( i_start > i_end ) return false;
 209     if ( (size_t)(i_end - i_start) > (*pp_segment)->i_size - 1 ) return false;
 210     if ( i_end > (*pp_segment)->i_size - 1 ) return false;
 211
 212     SegmentDoSplit( *pp_segment, i_start, i_end, &p_segment_left, &p_segment_middle, &p_segment_right );
 213     if ( !p_segment_middle )
 214     {
 215         /* Failed */
 216         text_segment_Delete( p_segment_left->s );
 217         free( p_segment_left );
 218         text_segment_Delete( p_segment_right->s );
 219         free( p_segment_right );
 220         return false;
 221     }
 222
 223     tx3g_segment_t *p_next3g = (*pp_segment)->p_next3g;
 224     text_segment_Delete( (*pp_segment)->s );
 225     free( *pp_segment );
 226     *pp_segment = ( p_segment_left ) ? p_segment_left : p_segment_middle ;
 227     if ( p_prev ) p_prev->p_next3g = *pp_segment;
 228
 229     if ( p_segment_right )
 230         p_segment_right->p_next3g = p_next3g;
 231     else
 232         p_segment_middle->p_next3g = p_next3g;
 233
 234     if( p_segment_middle->s->style )
 235         text_style_Merge( p_segment_middle->s->style, p_styles, true );
 236     else
 237         p_segment_middle->s->style = text_style_Duplicate( p_styles );
 238
 239     return true;
 240 }
 241
 242 /* Creates a new segment using the given style and split existing ones according
 243    to the start & end offsets */
 244 static void ApplySegmentStyle( tx3g_segment_t **pp_segment, const uint16_t i_absstart,
 245                                const uint16_t i_absend, const text_style_t *p_styles )
 246 {
 247     /* find the matching segment */
 248     uint16_t i_curstart = 0;
 249     tx3g_segment_t *p_prev = NULL;
 250     tx3g_segment_t *p_cur = *pp_segment;
 251     while ( p_cur )
 252     {
 253         uint16_t i_curend = i_curstart + p_cur->i_size - 1;
 254         if ( (i_absstart >= i_curstart) && (i_absend <= i_curend) )
 255         {
 256             /* segment found */
 257             if ( !SegmentSplit( p_prev, &p_cur, i_absstart - i_curstart,
 258                                 i_absend - i_curstart, p_styles ) )
 259                 return;
 260             if ( !p_prev ) *pp_segment = p_cur;
 261             break;
 262         }
 263         else
 264         {
 265             i_curstart += p_cur->i_size;
 266             p_prev = p_cur;
 267             p_cur = p_cur->p_next3g;
 268         }
 269     }
 270 }
 271
 272 /* Do relative size conversion using default style size (from stsd),
 273    as the line should always be 5%. Apply to each segment specific text size */
 274 static void FontSizeConvert( const text_style_t *p_reference, text_style_t *p_style )
 275 {
 276     if( unlikely(!p_style) )
 277     {
 278         return;
 279     }
 280     else if( unlikely(!p_reference) || p_reference->i_font_size == 0 )
 281     {
 282         p_style->i_font_size = 0;
 283         p_style->f_font_relsize = 5.0;
 284     }
 285     else
 286     {
 287         p_style->f_font_relsize = 5.0 * (float) p_style->i_font_size / p_reference->i_font_size;
 288         p_style->i_font_size = 0;
 289     }
 290 }
 291
 292 /*****************************************************************************
 293  * Decode:
 294  *****************************************************************************/
 295 static int Decode( decoder_t *p_dec, block_t *p_block )
 296 {
 297     subpicture_t  *p_spu = NULL;
 298
 299     if( p_block == NULL ) /* No Drain */
 300         return VLCDEC_SUCCESS;
 301
 302     if( ( p_block->i_flags & (BLOCK_FLAG_CORRUPTED) ) ||
 303           p_block->i_buffer < sizeof(uint16_t) )
 304     {
 305         block_Release( p_block );
 306         return VLCDEC_SUCCESS;
 307     }
 308
 309     uint8_t *p_buf = p_block->p_buffer;
 310
 311     /* Read our raw string and create the styled segment for HTML */
 312     uint16_t i_psz_bytelength = GetWBE( p_buf );
 313     if( p_block->i_buffer < i_psz_bytelength + 2U )
 314     {
 315         block_Release( p_block );
 316         return VLCDEC_SUCCESS;
 317     }
 318
 319     const uint8_t *p_pszstart = p_block->p_buffer + sizeof(uint16_t);
 320     char *psz_subtitle;
 321     if ( i_psz_bytelength > 2 &&
 322          ( !memcmp( p_pszstart, "\xFE\xFF", 2 ) || !memcmp( p_pszstart, "\xFF\xFE", 2 ) )
 323        )
 324     {
 325         psz_subtitle = FromCharset( "UTF-16", p_pszstart, i_psz_bytelength );
 326         if ( !psz_subtitle )
 327             return VLCDEC_SUCCESS;
 328     }
 329     else
 330     {
 331         psz_subtitle = strndup( (const char*) p_pszstart, i_psz_bytelength );
 332         if ( !psz_subtitle )
 333             return VLCDEC_SUCCESS;
 334     }
 335     p_buf += i_psz_bytelength + sizeof(uint16_t);
 336
 337     for( uint16_t i=0; i < i_psz_bytelength; i++ )
 338      if ( psz_subtitle[i] == '\r' ) psz_subtitle[i] = '\n';
 339
 340     tx3g_segment_t *p_segment3g = tx3g_segment_New( psz_subtitle );
 341     p_segment3g->i_size = str8len( psz_subtitle );
 342     free( psz_subtitle );
 343
 344     if ( !p_segment3g->s->psz_text )
 345     {
 346         text_segment_Delete( p_segment3g->s );
 347         free( p_segment3g );
 348         return VLCDEC_SUCCESS;
 349     }
 350
 351     /* Create the subpicture unit */
 352     p_spu = decoder_NewSubpictureText( p_dec );
 353     if( !p_spu )
 354     {
 355         text_segment_Delete( p_segment3g->s );
 356         free( p_segment3g );
 357         return VLCDEC_SUCCESS;
 358     }
 359
 360     subtext_updater_sys_t *p_spu_sys = p_spu->updater.p_sys;
 361     const text_style_t *p_root_style = (text_style_t *) p_dec->p_sys;
 362
 363     mp4_box_iterator_t it;
 364     mp4_box_iterator_Init( &it, p_buf,
 365                            p_block->i_buffer - (p_buf - p_block->p_buffer) );
 366     /* Parse our styles */
 367     if( p_dec->fmt_in.i_codec != VLC_CODEC_QTXT )
 368     while( mp4_box_iterator_Next( &it ) )
 369     {
 370         switch( it.i_type )
 371         {
 372
 373         case VLC_FOURCC('s','t','y','l'):
 374         {
 375             if( it.i_payload < 14 )
 376                 break;
 377
 378             uint16_t i_nbrecords = GetWBE(it.p_payload);
 379             uint16_t i_cur_record = 0;
 380
 381             it.p_payload += 2; it.i_payload -= 2;
 382             while( i_cur_record++ < i_nbrecords && it.i_payload >= 12 )
 383             {
 384                 uint16_t i_start = __MIN( GetWBE(it.p_payload), i_psz_bytelength - 1 );
 385                 uint16_t i_end =  GetWBE(it.p_payload + 2); /* index is past last char */
 386                 if( i_start < i_end )
 387                 {
 388                     i_end = VLC_CLIP( i_end - 1, i_start, i_psz_bytelength - 1 );
 389
 390                     text_style_t *p_style = text_style_Create( STYLE_NO_DEFAULTS );
 391                     if( p_style )
 392                     {
 393                         if( (p_style->i_style_flags = ConvertToVLCFlags( it.p_payload[6] )) )
 394                             p_style->i_features |= STYLE_HAS_FLAGS;
 395                         p_style->i_font_size = it.p_payload[7];
 396                         p_style->i_font_color = GetDWBE(&it.p_payload[8]) >> 8;// RGBA -> RGB
 397                         p_style->i_font_alpha = GetDWBE(&it.p_payload[8]) & 0xFF;
 398                         p_style->i_features |= STYLE_HAS_FONT_COLOR | STYLE_HAS_FONT_ALPHA;
 399                         ApplySegmentStyle( &p_segment3g, i_start, i_end, p_style );
 400                         text_style_Delete( p_style );
 401                     }
 402                 }
 403
 404                 it.p_payload += 12; it.i_payload -= 12;
 405             }
 406         }   break;
 407
 408
 409         default:
 410             break;
 411
 412         }
 413     }
 414
 415     p_spu->i_start    = p_block->i_pts;
 416     p_spu->i_stop     = p_block->i_pts + p_block->i_length;
 417     p_spu->b_ephemer  = (p_block->i_length == 0);
 418     p_spu->b_absolute = false;
 419
 420     p_spu_sys->region.align = SUBPICTURE_ALIGN_BOTTOM;
 421
 422     text_style_Merge( p_spu_sys->p_default_style, p_root_style, true );
 423     FontSizeConvert( p_root_style, p_spu_sys->p_default_style );
 424
 425     /* Unwrap */
 426     text_segment_t *p_text_segments = p_segment3g->s;
 427     text_segment_t *p_cur = p_text_segments;
 428     while( p_segment3g )
 429     {
 430         FontSizeConvert( p_root_style, p_segment3g->s->style );
 431
 432         tx3g_segment_t * p_old = p_segment3g;
 433         p_segment3g = p_segment3g->p_next3g;
 434         free( p_old );
 435         if( p_segment3g )
 436             p_cur->p_next = p_segment3g->s;
 437         p_cur = p_cur->p_next;
 438     }
 439
 440     p_spu_sys->region.p_segments = p_text_segments;
 441
 442     block_Release( p_block );
 443
 444     decoder_QueueSub( p_dec, p_spu );
 445     return VLCDEC_SUCCESS;
 446 }
 447
 448 /*****************************************************************************
 449  * Extradata Parsing
 450  *****************************************************************************/
 451 static void ParseExtradataTx3g( decoder_t *p_dec )
 452 {
 453     text_style_t *p_style = (text_style_t *) p_dec->p_sys;
 454     const uint8_t *p_extra = p_dec->fmt_in.p_extra;
 455
 456     if( p_dec->fmt_in.i_extra < 32 )
 457         return;
 458
 459     /* DF @0 */
 460     /* Just @4 */
 461
 462     /* BGColor @6 */
 463     p_style->i_background_color = GetDWBE(&p_extra[6]) >> 8;
 464     p_style->i_background_alpha = p_extra[9];
 465     p_style->i_features |= STYLE_HAS_BACKGROUND_COLOR|STYLE_HAS_BACKGROUND_ALPHA;
 466
 467     /* BoxRecord @10 */
 468
 469     /* StyleRecord @18 */
 470     p_style->i_style_flags = ConvertToVLCFlags( p_extra[24] );
 471     if( p_style->i_style_flags )
 472         p_style->i_features |= STYLE_HAS_FLAGS;
 473     p_style->i_font_size = p_extra[25];
 474     p_style->i_font_color = GetDWBE(&p_extra[26]) >> 8;// RGBA -> RGB
 475     p_style->i_font_alpha = p_extra[29];
 476     p_style->i_features |= STYLE_HAS_FONT_COLOR | STYLE_HAS_FONT_ALPHA;
 477
 478     /* FontTableBox @30 */
 479 }
 480
 481 static void ParseExtradataTextMedia( decoder_t *p_dec )
 482 {
 483     text_style_t *p_style = (text_style_t *) p_dec->p_sys;
 484     const uint8_t *p_extra = p_dec->fmt_in.p_extra;
 485
 486     if( p_dec->fmt_in.i_extra < 44 )
 487         return;
 488
 489     /* DF @0 */
 490     /* Just @4 */
 491
 492     /* BGColor @8, read top of 16 bits */
 493     p_style->i_background_color = (p_extra[8]  << 16) |
 494                                   (p_extra[10] <<  8) |
 495                                    p_extra[12];
 496     p_style->i_features |= STYLE_HAS_BACKGROUND_COLOR;
 497
 498     /* BoxRecord @14 */
 499     /* Reserved 64 @22 */
 500     /* Font # @30 */
 501
 502     /* Font Face @32 */
 503     p_style->i_style_flags = ConvertToVLCFlags( GetWBE(&p_extra[32]) );
 504     if( p_style->i_style_flags )
 505         p_style->i_features |= STYLE_HAS_FLAGS;
 506     /* Reserved 8 @34 */
 507     /* Reserved 16 @35 */
 508     /* FGColor @37 */
 509     p_style->i_font_color = (p_extra[37] << 16) |
 510                             (p_extra[39] <<  8) |
 511                              p_extra[41];
 512     p_style->i_features |= STYLE_HAS_FONT_COLOR;
 513
 514     /* FontName Pascal (8 + string) @43 */
 515 }
 516 /*****************************************************************************
 517  * Decoder entry/exit points
 518  *****************************************************************************/
 519 static void CloseDecoder( vlc_object_t *p_this )
 520 {
 521     decoder_t     *p_dec = (decoder_t *) p_this;
 522     text_style_Delete( (text_style_t *) p_dec->p_sys );
 523 }
 524
 525 static int OpenDecoder( vlc_object_t *p_this )
 526 {
 527     decoder_t     *p_dec = (decoder_t *) p_this;
 528
 529     if( p_dec->fmt_in.i_codec != VLC_CODEC_TX3G &&
 530         p_dec->fmt_in.i_codec != VLC_CODEC_QTXT )
 531         return VLC_EGENERIC;
 532
 533     p_dec->pf_decode = Decode;
 534
 535     p_dec->p_sys = text_style_Create( STYLE_NO_DEFAULTS );
 536     if( !p_dec->p_sys )
 537         return VLC_ENOMEM;
 538
 539     if( p_dec->fmt_in.i_codec == VLC_CODEC_TX3G )
 540         ParseExtradataTx3g( p_dec );
 541     else
 542         ParseExtradataTextMedia( p_dec );
 543
 544     p_dec->fmt_out.i_codec = VLC_CODEC_TEXT;
 545
 546     return VLC_SUCCESS;
 547 }
 548
 549 /*****************************************************************************
 550  * Encoder entry/exit
 551  *****************************************************************************/
 552 #ifdef ENABLE_SOUT
 553 static void FillExtradataTx3g( void **pp_extra, int *pi_extra )
 554 {
 555     size_t i_extra = 32 + 37;
 556     uint8_t *p_extra = calloc( 1, i_extra );
 557     if( p_extra )
 558     {
 559         p_extra[4] = 0x01;/* 1  center, horizontal */
 560         p_extra[5] = 0xFF;/* -1 bottom, vertical */
 561         SetDWBE( &p_extra[6],  0x000000FFU ); /* bgcolor */
 562         p_extra[25] = STYLE_DEFAULT_FONT_SIZE;
 563         SetDWBE( &p_extra[26], 0xFFFFFFFFU ); /* fgcolor */
 564
 565         /* FontTableBox */
 566         SetDWBE(&p_extra[32], 8 + 2 + 6 + 11 + 10);
 567         memcpy(&p_extra[36], "ftab", 4);
 568
 569         SetWBE(&p_extra[40], 3); /* entry count */
 570         /* Font Record 0 */
 571         p_extra[41] = 5;
 572         memcpy(&p_extra[42], "Serif", 5);
 573         /* Font Record 1 */
 574         p_extra[47] = 10;
 575         memcpy(&p_extra[48], "Sans-serif", 10);
 576         /* Font Record 2 */
 577         p_extra[58] = 9;
 578         memcpy(&p_extra[59], "Monospace", 9);
 579
 580         *pp_extra = p_extra;
 581         *pi_extra = i_extra;
 582     }
 583 }
 584
 585 static int OpenEncoder( vlc_object_t *p_this )
 586 {
 587     encoder_t *p_enc = (encoder_t *)p_this;
 588
 589     if( p_enc->fmt_out.i_codec != VLC_CODEC_TX3G )
 590         return VLC_EGENERIC;
 591
 592     p_enc->fmt_in.i_codec = VLC_CODEC_TEXT;
 593
 594     p_enc->p_sys = NULL;
 595
 596     p_enc->pf_encode_sub = Encode;
 597     p_enc->fmt_out.i_cat = SPU_ES;
 598
 599     if( !p_enc->fmt_out.i_extra )
 600         FillExtradataTx3g( &p_enc->fmt_out.p_extra, &p_enc->fmt_out.i_extra );
 601
 602     return VLC_SUCCESS;
 603 }
 604
 605 static int ConvertFromVLCFlags( const text_style_t *p_style )
 606 {
 607     int i_atomflags = 0;
 608     if( p_style->i_features & STYLE_HAS_FLAGS )
 609     {
 610         if ( p_style->i_style_flags & STYLE_BOLD )
 611             i_atomflags |= FONT_FACE_BOLD;
 612         if ( p_style->i_style_flags & STYLE_ITALIC )
 613             i_atomflags |= FONT_FACE_ITALIC;
 614         if ( p_style->i_style_flags & STYLE_UNDERLINE )
 615             i_atomflags |= FONT_FACE_UNDERLINE;
 616     }
 617     return i_atomflags;
 618 }
 619
 620 static uint32_t ConvertFromVLCColor( const text_style_t *p_style )
 621 {
 622     uint32_t rgba = 0;
 623     if( p_style->i_features & STYLE_HAS_FONT_COLOR )
 624         rgba = ((uint32_t)p_style->i_font_color) << 8;
 625     else
 626         rgba = 0xFFFFFF00U;
 627     if( p_style->i_features & STYLE_HAS_FONT_ALPHA )
 628         rgba |= p_style->i_font_alpha;
 629     else
 630         rgba |= 0xFF;
 631     return rgba;
 632 }
 633
 634 static bool NeedStyling( const text_segment_t *p_segment )
 635 {
 636     const text_style_t *p_style = p_segment->style;
 637     if( !p_style )
 638         return false;
 639
 640     if( p_style->i_features & STYLE_HAS_FLAGS )
 641     {
 642         if( p_style->i_style_flags & (STYLE_BOLD|STYLE_ITALIC|STYLE_UNDERLINE) )
 643             return true;
 644     }
 645
 646     if( p_style->i_features & (STYLE_HAS_FONT_COLOR|STYLE_HAS_FONT_ALPHA) )
 647         return true;
 648
 649     return false;
 650 }
 651
 652 static block_t *GetStylBlock( const text_segment_t *p_segment, size_t i_styles )
 653 {
 654     size_t i_start = 0;
 655     block_t *p_styl = block_Alloc( 10 + 12 * i_styles );
 656     if( p_styl )
 657     {
 658         SetDWBE( p_styl->p_buffer, p_styl->i_buffer );
 659         memcpy( &p_styl->p_buffer[4], "styl", 4 );
 660         SetWBE( &p_styl->p_buffer[8], i_styles );
 661         p_styl->i_buffer = 10;
 662         for( ; p_segment; p_segment = p_segment->p_next )
 663         {
 664             size_t i_len = str8len( p_segment->psz_text );
 665             if( NeedStyling( p_segment ) )
 666             {
 667                 uint8_t *p = &p_styl->p_buffer[p_styl->i_buffer];
 668                 SetWBE( &p[0], i_start );
 669                 SetWBE( &p[2], i_start + i_len );
 670                 SetWBE( &p[4], 0 );
 671                 p[6] = ConvertFromVLCFlags( p_segment->style );
 672                 p[7] = STYLE_DEFAULT_FONT_SIZE;
 673                 SetDWBE(&p[8], ConvertFromVLCColor( p_segment->style ) );
 674                 p_styl->i_buffer += 12;
 675             }
 676             i_start += i_len;
 677         }
 678     }
 679     return p_styl;
 680 }
 681
 682 static block_t * Encode( encoder_t *p_enc, subpicture_t *p_spu )
 683 {
 684     VLC_UNUSED(p_enc);
 685     const text_segment_t *p_segments = (p_spu->p_region)
 686                                      ? p_spu->p_region->p_text
 687                                      : NULL;
 688     size_t i_len = 0;
 689     size_t i_styles = 0;
 690
 691     for(const text_segment_t  *p_segment = p_segments;
 692                                p_segment; p_segment = p_segment->p_next )
 693     {
 694         if( p_segment->style )
 695             i_styles++;
 696         i_len += strlen( p_segment->psz_text );
 697     }
 698
 699     block_t *p_block = block_Alloc( i_len + 2 );
 700     if( !p_block )
 701         return NULL;
 702
 703     SetWBE(p_block->p_buffer, i_len);
 704     p_block->i_buffer = 2;
 705     for(const text_segment_t  *p_segment = p_segments;
 706                                p_segment; p_segment = p_segment->p_next )
 707     {
 708         size_t i_seglen = strlen(p_segment->psz_text);
 709         memcpy(&p_block->p_buffer[p_block->i_buffer],
 710                 p_segment->psz_text, i_seglen);
 711         p_block->i_buffer += i_seglen;
 712     }
 713     p_block->i_dts = p_block->i_pts = p_spu->i_start;
 714     p_block->i_length = p_spu->i_stop - p_spu->i_start;
 715
 716     if( i_styles > 0 )
 717         p_block->p_next = GetStylBlock( p_segments, i_styles );
 718
 719     return block_ChainGather( p_block );
 720 }
 721 #endif