modules/codec/libass.c

   1 /*****************************************************************************
   2  * SSA/ASS subtitle decoder using libass.
   3  *****************************************************************************
   4  * Copyright (C) 2008-2009 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@videolan.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 #   include "config.h"
  30 #endif
  31
  32 #include <string.h>
  33 #include <limits.h>
  34 #include <assert.h>
  35 #include <math.h>
  36
  37 #include <vlc_common.h>
  38 #include <vlc_plugin.h>
  39 #include <vlc_codec.h>
  40 #include <vlc_input.h>
  41 #include <vlc_dialog.h>
  42
  43 #include <ass/ass.h>
  44
  45 #if defined(_WIN32)
  46 #   include <vlc_charset.h>
  47 #endif
  48
  49 /*****************************************************************************
  50  * Module descriptor
  51  *****************************************************************************/
  52 static int  Create ( vlc_object_t * );
  53 static void Destroy( vlc_object_t * );
  54
  55 vlc_module_begin ()
  56     set_shortname( N_("Subtitles (advanced)"))
  57     set_description( N_("Subtitle renderers using libass") )
  58     set_capability( "spu decoder", 100 )
  59     set_category( CAT_INPUT )
  60     set_subcategory( SUBCAT_INPUT_SCODEC )
  61     set_callbacks( Create, Destroy )
  62 vlc_module_end ()
  63
  64 /*****************************************************************************
  65  * Local prototypes
  66  *****************************************************************************/
  67 static int DecodeBlock( decoder_t *, block_t * );
  68 static void Flush( decoder_t * );
  69
  70 /* */
  71 struct decoder_sys_t
  72 {
  73     mtime_t        i_max_stop;
  74
  75     /* The following fields of decoder_sys_t are shared between decoder and spu units */
  76     vlc_mutex_t    lock;
  77     int            i_refcount;
  78
  79     /* */
  80     ASS_Library    *p_library;
  81     ASS_Renderer   *p_renderer;
  82     video_format_t fmt;
  83
  84     /* */
  85     ASS_Track      *p_track;
  86 };
  87 static void DecSysRelease( decoder_sys_t *p_sys );
  88 static void DecSysHold( decoder_sys_t *p_sys );
  89
  90 /* */
  91 static int SubpictureValidate( subpicture_t *,
  92                                bool, const video_format_t *,
  93                                bool, const video_format_t *,
  94                                mtime_t );
  95 static void SubpictureUpdate( subpicture_t *,
  96                               const video_format_t *,
  97                               const video_format_t *,
  98                               mtime_t );
  99 static void SubpictureDestroy( subpicture_t * );
 100
 101 struct subpicture_updater_sys_t
 102 {
 103     decoder_sys_t *p_dec_sys;
 104     void          *p_subs_data;
 105     int           i_subs_len;
 106     mtime_t       i_pts;
 107
 108     ASS_Image     *p_img;
 109 };
 110
 111 typedef struct
 112 {
 113     int x0;
 114     int y0;
 115     int x1;
 116     int y1;
 117 } rectangle_t;
 118
 119 static int BuildRegions( rectangle_t *p_region, int i_max_region, ASS_Image *p_img_list, int i_width, int i_height );
 120 static void RegionDraw( subpicture_region_t *p_region, ASS_Image *p_img );
 121
 122 //#define DEBUG_REGION
 123
 124 /*****************************************************************************
 125  * Create: Open libass decoder.
 126  *****************************************************************************/
 127 static int Create( vlc_object_t *p_this )
 128 {
 129     decoder_t *p_dec = (decoder_t *)p_this;
 130     decoder_sys_t *p_sys;
 131
 132     if( p_dec->fmt_in.i_codec != VLC_CODEC_SSA )
 133         return VLC_EGENERIC;
 134
 135     p_dec->pf_decode = DecodeBlock;
 136     p_dec->pf_flush  = Flush;
 137
 138     p_dec->p_sys = p_sys = malloc( sizeof( decoder_sys_t ) );
 139     if( !p_sys )
 140         return VLC_ENOMEM;
 141
 142     /* */
 143     vlc_mutex_init( &p_sys->lock );
 144     p_sys->i_refcount = 1;
 145     memset( &p_sys->fmt, 0, sizeof(p_sys->fmt) );
 146     p_sys->i_max_stop = VLC_TS_INVALID;
 147     p_sys->p_library  = NULL;
 148     p_sys->p_renderer = NULL;
 149     p_sys->p_track    = NULL;
 150
 151     /* Create libass library */
 152     ASS_Library *p_library = p_sys->p_library = ass_library_init();
 153     if( !p_library )
 154     {
 155         msg_Warn( p_dec, "Libass library creation failed" );
 156         DecSysRelease( p_sys );
 157         return VLC_EGENERIC;
 158     }
 159
 160     /* load attachments */
 161     input_attachment_t  **pp_attachments;
 162     int                   i_attachments;
 163     if( decoder_GetInputAttachments( p_dec, &pp_attachments, &i_attachments ))
 164     {
 165         i_attachments = 0;
 166         pp_attachments = NULL;
 167     }
 168     for( int k = 0; k < i_attachments; k++ )
 169     {
 170         input_attachment_t *p_attach = pp_attachments[k];
 171
 172         bool found = false;
 173
 174         /* Check mimetype*/
 175         if( !strcasecmp( p_attach->psz_mime, "application/x-truetype-font" ) )
 176             found = true;
 177         /* Then extension */
 178         else if( !found && strlen( p_attach->psz_name ) > 4 )
 179         {
 180             char *ext = p_attach->psz_name + strlen( p_attach->psz_name ) - 4;
 181
 182             if( !strcasecmp( ext, ".ttf" ) || !strcasecmp( ext, ".otf" ) || !strcasecmp( ext, ".ttc" ) )
 183                 found = true;
 184         }
 185
 186         if( found )
 187         {
 188             msg_Dbg( p_dec, "adding embedded font %s", p_attach->psz_name );
 189
 190             ass_add_font( p_sys->p_library, p_attach->psz_name, p_attach->p_data, p_attach->i_data );
 191         }
 192         vlc_input_attachment_Delete( p_attach );
 193     }
 194     free( pp_attachments );
 195
 196     ass_set_extract_fonts( p_library, true );
 197     ass_set_style_overrides( p_library, NULL );
 198
 199     /* Create the renderer */
 200     ASS_Renderer *p_renderer = p_sys->p_renderer = ass_renderer_init( p_library );
 201     if( !p_renderer )
 202     {
 203         msg_Warn( p_dec, "Libass renderer creation failed" );
 204         DecSysRelease( p_sys );
 205         return VLC_EGENERIC;
 206     }
 207
 208     ass_set_use_margins( p_renderer, false);
 209     //if( false )
 210     //    ass_set_margins( p_renderer, int t, int b, int l, int r);
 211     ass_set_font_scale( p_renderer, 1.0 );
 212     ass_set_line_spacing( p_renderer, 0.0 );
 213
 214 #if defined( __ANDROID__ )
 215     const char *psz_font, *psz_family;
 216     const char *psz_font_droid = "/system/fonts/DroidSans-Bold.ttf";
 217     const char *psz_family_droid = "Droid Sans Bold";
 218     const char *psz_font_noto = "/system/fonts/NotoSansCJK-Regular.ttc";
 219     const char *psz_family_noto = "Noto Sans";
 220
 221     // Workaround for Android 5.0+, since libass doesn't parse the XML yet
 222     if( access( psz_font_noto, R_OK ) != -1 )
 223     {
 224         psz_font = psz_font_noto;
 225         psz_family = psz_family_noto;
 226     }
 227     else
 228     {
 229         psz_font = psz_font_droid;
 230         psz_family = psz_family_droid;
 231     }
 232
 233 #elif defined( __APPLE__ )
 234     const char *psz_font = NULL; /* We don't ship a default font with VLC */
 235     const char *psz_family = "Helvetica Neue"; /* Use HN if we can't find anything more suitable - Arial is not on all Apple platforms */
 236 #else
 237     const char *psz_font = NULL; /* We don't ship a default font with VLC */
 238     const char *psz_family = "Arial"; /* Use Arial if we can't find anything more suitable */
 239 #endif
 240
 241 #ifdef HAVE_FONTCONFIG
 242 #if defined(_WIN32)
 243     vlc_dialog_id *p_dialog_id =
 244         vlc_dialog_display_progress( p_dec, true, 0.0, NULL,
 245                                     _("Building font cache"),
 246                                     _( "Please wait while your font cache is rebuilt.\n"
 247                                     "This should take less than a minute." ) );
 248 #endif
 249     ass_set_fonts( p_renderer, psz_font, psz_family, ASS_FONTPROVIDER_AUTODETECT, NULL, 1 );  // setup default font/family
 250 #if defined(_WIN32)
 251     if( p_dialog_id != 0 )
 252         vlc_dialog_release( p_dec, p_dialog_id );
 253 #endif
 254 #else
 255     ass_set_fonts( p_renderer, psz_font, psz_family, ASS_FONTPROVIDER_AUTODETECT, NULL, 0 );
 256 #endif
 257
 258     /* Anything else than NONE will break smooth img updating.
 259        TODO: List and force ASS_HINTING_LIGHT for known problematic fonts */
 260     ass_set_hinting( p_renderer, ASS_HINTING_NONE );
 261
 262     /* Add a track */
 263     ASS_Track *p_track = p_sys->p_track = ass_new_track( p_sys->p_library );
 264     if( !p_track )
 265     {
 266         DecSysRelease( p_sys );
 267         return VLC_EGENERIC;
 268     }
 269     ass_process_codec_private( p_track, p_dec->fmt_in.p_extra, p_dec->fmt_in.i_extra );
 270
 271     p_dec->fmt_out.i_codec = VLC_CODEC_RGBA;
 272
 273     return VLC_SUCCESS;
 274 }
 275
 276 /*****************************************************************************
 277  * Destroy: finish
 278  *****************************************************************************/
 279 static void Destroy( vlc_object_t *p_this )
 280 {
 281     decoder_t *p_dec = (decoder_t *)p_this;
 282
 283     DecSysRelease( p_dec->p_sys );
 284 }
 285
 286 static void DecSysHold( decoder_sys_t *p_sys )
 287 {
 288     vlc_mutex_lock( &p_sys->lock );
 289     p_sys->i_refcount++;
 290     vlc_mutex_unlock( &p_sys->lock );
 291 }
 292 static void DecSysRelease( decoder_sys_t *p_sys )
 293 {
 294     /* */
 295     vlc_mutex_lock( &p_sys->lock );
 296     p_sys->i_refcount--;
 297     if( p_sys->i_refcount > 0 )
 298     {
 299         vlc_mutex_unlock( &p_sys->lock );
 300         return;
 301     }
 302     vlc_mutex_unlock( &p_sys->lock );
 303     vlc_mutex_destroy( &p_sys->lock );
 304
 305     if( p_sys->p_track )
 306         ass_free_track( p_sys->p_track );
 307     if( p_sys->p_renderer )
 308         ass_renderer_done( p_sys->p_renderer );
 309     if( p_sys->p_library )
 310         ass_library_done( p_sys->p_library );
 311
 312     free( p_sys );
 313 }
 314
 315 /*****************************************************************************
 316  * Flush:
 317  *****************************************************************************/
 318 static void Flush( decoder_t *p_dec )
 319 {
 320     decoder_sys_t *p_sys = p_dec->p_sys;
 321
 322     p_sys->i_max_stop = VLC_TS_INVALID;
 323 }
 324
 325 /****************************************************************************
 326  * DecodeBlock:
 327  ****************************************************************************/
 328 static int DecodeBlock( decoder_t *p_dec, block_t *p_block )
 329 {
 330     decoder_sys_t *p_sys = p_dec->p_sys;
 331
 332     subpicture_t *p_spu = NULL;
 333
 334     if( p_block == NULL ) /* No Drain */
 335         return VLCDEC_SUCCESS;
 336
 337     if( p_block->i_flags & BLOCK_FLAG_CORRUPTED )
 338     {
 339         Flush( p_dec );
 340         block_Release( p_block );
 341         return VLCDEC_SUCCESS;
 342     }
 343
 344     if( p_block->i_buffer == 0 || p_block->p_buffer[0] == '\0' )
 345     {
 346         block_Release( p_block );
 347         return VLCDEC_SUCCESS;
 348     }
 349
 350     subpicture_updater_sys_t *p_spu_sys = malloc( sizeof(*p_spu_sys) );
 351     if( !p_spu_sys )
 352     {
 353         block_Release( p_block );
 354         return VLCDEC_SUCCESS;
 355     }
 356
 357     subpicture_updater_t updater = {
 358         .pf_validate = SubpictureValidate,
 359         .pf_update   = SubpictureUpdate,
 360         .pf_destroy  = SubpictureDestroy,
 361         .p_sys       = p_spu_sys,
 362     };
 363     p_spu = decoder_NewSubpicture( p_dec, &updater );
 364     if( !p_spu )
 365     {
 366         msg_Warn( p_dec, "can't get spu buffer" );
 367         free( p_spu_sys );
 368         block_Release( p_block );
 369         return VLCDEC_SUCCESS;
 370     }
 371
 372     p_spu_sys->p_img = NULL;
 373     p_spu_sys->p_dec_sys = p_sys;
 374     p_spu_sys->i_subs_len = p_block->i_buffer;
 375     p_spu_sys->p_subs_data = malloc( p_block->i_buffer );
 376     p_spu_sys->i_pts = p_block->i_pts;
 377     if( !p_spu_sys->p_subs_data )
 378     {
 379         subpicture_Delete( p_spu );
 380         block_Release( p_block );
 381         return VLCDEC_SUCCESS;
 382     }
 383     memcpy( p_spu_sys->p_subs_data, p_block->p_buffer,
 384             p_block->i_buffer );
 385
 386     p_spu->i_start = p_block->i_pts;
 387     p_spu->i_stop = __MAX( p_sys->i_max_stop, p_block->i_pts + p_block->i_length );
 388     p_spu->b_ephemer = true;
 389     p_spu->b_absolute = true;
 390
 391     p_sys->i_max_stop = p_spu->i_stop;
 392
 393     vlc_mutex_lock( &p_sys->lock );
 394     if( p_sys->p_track )
 395     {
 396         ass_process_chunk( p_sys->p_track, p_spu_sys->p_subs_data, p_spu_sys->i_subs_len,
 397                            p_block->i_pts / 1000, p_block->i_length / 1000 );
 398     }
 399     vlc_mutex_unlock( &p_sys->lock );
 400
 401     DecSysHold( p_sys ); /* Keep a reference for the returned subpicture */
 402
 403     block_Release( p_block );
 404
 405     decoder_QueueSub( p_dec, p_spu );
 406     return VLCDEC_SUCCESS;
 407 }
 408
 409 /****************************************************************************
 410  *
 411  ****************************************************************************/
 412 static int SubpictureValidate( subpicture_t *p_subpic,
 413                                bool b_fmt_src, const video_format_t *p_fmt_src,
 414                                bool b_fmt_dst, const video_format_t *p_fmt_dst,
 415                                mtime_t i_ts )
 416 {
 417     decoder_sys_t *p_sys = p_subpic->updater.p_sys->p_dec_sys;
 418
 419     vlc_mutex_lock( &p_sys->lock );
 420
 421     video_format_t fmt = *p_fmt_dst;
 422     fmt.i_chroma         = VLC_CODEC_RGBA;
 423     fmt.i_bits_per_pixel = 0;
 424     fmt.i_x_offset       = 0;
 425     fmt.i_y_offset       = 0;
 426     if( b_fmt_src || b_fmt_dst )
 427     {
 428         ass_set_frame_size( p_sys->p_renderer, fmt.i_visible_width, fmt.i_visible_height );
 429         const double src_ratio = (double)p_fmt_src->i_visible_width / p_fmt_src->i_visible_height;
 430         const double dst_ratio = (double)p_fmt_dst->i_visible_width / p_fmt_dst->i_visible_height;
 431         ass_set_aspect_ratio( p_sys->p_renderer, dst_ratio / src_ratio, 1 );
 432         p_sys->fmt = fmt;
 433     }
 434
 435     /* */
 436     const mtime_t i_stream_date = p_subpic->updater.p_sys->i_pts + (i_ts - p_subpic->i_start);
 437     int i_changed;
 438     ASS_Image *p_img = ass_render_frame( p_sys->p_renderer, p_sys->p_track,
 439                                          i_stream_date/1000, &i_changed );
 440
 441     if( !i_changed && !b_fmt_src && !b_fmt_dst &&
 442         (p_img != NULL) == (p_subpic->p_region != NULL) )
 443     {
 444         vlc_mutex_unlock( &p_sys->lock );
 445         return VLC_SUCCESS;
 446     }
 447     p_subpic->updater.p_sys->p_img = p_img;
 448
 449     /* The lock is released by SubpictureUpdate */
 450     return VLC_EGENERIC;
 451 }
 452
 453 static void SubpictureUpdate( subpicture_t *p_subpic,
 454                               const video_format_t *p_fmt_src,
 455                               const video_format_t *p_fmt_dst,
 456                               mtime_t i_ts )
 457 {
 458     VLC_UNUSED( p_fmt_src ); VLC_UNUSED( p_fmt_dst ); VLC_UNUSED( i_ts );
 459
 460     decoder_sys_t *p_sys = p_subpic->updater.p_sys->p_dec_sys;
 461
 462     video_format_t fmt = p_sys->fmt;
 463     ASS_Image *p_img = p_subpic->updater.p_sys->p_img;
 464
 465     /* */
 466     p_subpic->i_original_picture_height = fmt.i_visible_height;
 467     p_subpic->i_original_picture_width = fmt.i_visible_width;
 468
 469     /* XXX to improve efficiency we merge regions that are close minimizing
 470      * the lost surface.
 471      * libass tends to create a lot of small regions and thus spu engine
 472      * reinstanciate a lot the scaler, and as we do not support subpel blending
 473      * it looks ugly (text unaligned).
 474      */
 475     const int i_max_region = 4;
 476     rectangle_t region[i_max_region];
 477     const int i_region = BuildRegions( region, i_max_region, p_img, fmt.i_width, fmt.i_height );
 478
 479     if( i_region <= 0 )
 480     {
 481         vlc_mutex_unlock( &p_sys->lock );
 482         return;
 483     }
 484
 485     /* Allocate the regions and draw them */
 486     subpicture_region_t **pp_region_last = &p_subpic->p_region;
 487
 488     for( int i = 0; i < i_region; i++ )
 489     {
 490         subpicture_region_t *r;
 491         video_format_t fmt_region;
 492
 493         /* */
 494         fmt_region = fmt;
 495         fmt_region.i_width =
 496         fmt_region.i_visible_width  = region[i].x1 - region[i].x0;
 497         fmt_region.i_height =
 498         fmt_region.i_visible_height = region[i].y1 - region[i].y0;
 499
 500         r = subpicture_region_New( &fmt_region );
 501         if( !r )
 502             break;
 503         r->i_x = region[i].x0;
 504         r->i_y = region[i].y0;
 505         r->i_align = SUBPICTURE_ALIGN_TOP | SUBPICTURE_ALIGN_LEFT;
 506
 507         /* */
 508         RegionDraw( r, p_img );
 509
 510         /* */
 511         *pp_region_last = r;
 512         pp_region_last = &r->p_next;
 513     }
 514     vlc_mutex_unlock( &p_sys->lock );
 515
 516 }
 517 static void SubpictureDestroy( subpicture_t *p_subpic )
 518 {
 519     subpicture_updater_sys_t *p_sys = p_subpic->updater.p_sys;
 520
 521     DecSysRelease( p_sys->p_dec_sys );
 522     free( p_sys->p_subs_data );
 523     free( p_sys );
 524 }
 525
 526 static rectangle_t r_create( int x0, int y0, int x1, int y1 )
 527 {
 528     rectangle_t r = { x0, y0, x1, y1 };
 529     return r;
 530 }
 531 static rectangle_t r_img( const ASS_Image *p_img )
 532 {
 533     return r_create( p_img->dst_x, p_img->dst_y, p_img->dst_x+p_img->w, p_img->dst_y+p_img->h );
 534 }
 535 static void r_add( rectangle_t *r, const rectangle_t *n )
 536 {
 537     r->x0 = __MIN( r->x0, n->x0 );
 538     r->y0 = __MIN( r->y0, n->y0 );
 539     r->x1 = __MAX( r->x1, n->x1 );
 540     r->y1 = __MAX( r->y1, n->y1 );
 541 }
 542 static int r_surface( const rectangle_t *r )
 543 {
 544     return (r->x1-r->x0) * (r->y1-r->y0);
 545 }
 546 static bool r_overlap( const rectangle_t *a, const rectangle_t *b, int i_dx, int i_dy )
 547 {
 548     return  __MAX(a->x0-i_dx, b->x0) < __MIN( a->x1+i_dx, b->x1 ) &&
 549             __MAX(a->y0-i_dy, b->y0) < __MIN( a->y1+i_dy, b->y1 );
 550 }
 551
 552 static int BuildRegions( rectangle_t *p_region, int i_max_region, ASS_Image *p_img_list, int i_width, int i_height )
 553 {
 554     ASS_Image *p_tmp;
 555     int i_count;
 556
 557 #ifdef DEBUG_REGION
 558     int64_t i_ck_start = mdate();
 559 #endif
 560
 561     for( p_tmp = p_img_list, i_count = 0; p_tmp != NULL; p_tmp = p_tmp->next )
 562         if( p_tmp->w > 0 && p_tmp->h > 0 )
 563             i_count++;
 564     if( i_count <= 0 )
 565         return 0;
 566
 567     ASS_Image **pp_img = calloc( i_count, sizeof(*pp_img) );
 568     if( !pp_img )
 569         return 0;
 570
 571     for( p_tmp = p_img_list, i_count = 0; p_tmp != NULL; p_tmp = p_tmp->next )
 572         if( p_tmp->w > 0 && p_tmp->h > 0 )
 573             pp_img[i_count++] = p_tmp;
 574
 575     /* */
 576     const int i_w_inc = __MAX( ( i_width + 49 ) / 50, 32 );
 577     const int i_h_inc = __MAX( ( i_height + 99 ) / 100, 32 );
 578     int i_maxh = i_w_inc;
 579     int i_maxw = i_h_inc;
 580     int i_region;
 581     rectangle_t region[i_max_region+1];
 582
 583     i_region = 0;
 584     for( int i_used = 0; i_used < i_count; )
 585     {
 586         int n;
 587         for( n = 0; n < i_count; n++ )
 588         {
 589             if( pp_img[n] )
 590                 break;
 591         }
 592         assert( i_region < i_max_region + 1 );
 593         region[i_region++] = r_img( pp_img[n] );
 594         pp_img[n] = NULL; i_used++;
 595
 596         bool b_ok;
 597         do {
 598             b_ok = false;
 599             for( n = 0; n < i_count; n++ )
 600             {
 601                 ASS_Image *p_img = pp_img[n];
 602                 if( !p_img )
 603                     continue;
 604                 rectangle_t r = r_img( p_img );
 605
 606                 int k;
 607                 int i_best = -1;
 608                 int i_best_s = INT_MAX;
 609                 for( k = 0; k < i_region; k++ )
 610                 {
 611                     if( !r_overlap( &region[k], &r, i_maxw, i_maxh ) )
 612                         continue;
 613                     int s = r_surface( &r );
 614                     if( s < i_best_s )
 615                     {
 616                         i_best_s = s;
 617                         i_best = k;
 618                     }
 619                 }
 620                 if( i_best >= 0 )
 621                 {
 622                     r_add( &region[i_best], &r );
 623                     pp_img[n] = NULL; i_used++;
 624                     b_ok = true;
 625                 }
 626             }
 627         } while( b_ok );
 628
 629         if( i_region > i_max_region )
 630         {
 631             int i_best_i = -1;
 632             int i_best_j = -1;
 633             int i_best_ds = INT_MAX;
 634
 635             /* merge best */
 636             for( int i = 0; i < i_region; i++ )
 637             {
 638                 for( int j = i+1; j < i_region; j++ )
 639                 {
 640                     rectangle_t rect = region[i];
 641                     r_add( &rect, &region[j] );
 642                     int ds = r_surface( &rect ) - r_surface( &region[i] ) - r_surface( &region[j] );
 643
 644                     if( ds < i_best_ds )
 645                     {
 646                         i_best_i = i;
 647                         i_best_j = j;
 648                         i_best_ds = ds;
 649                     }
 650                 }
 651             }
 652 #ifdef DEBUG_REGION
 653             msg_Err( p_spu, "Merging %d and %d", i_best_i, i_best_j );
 654 #endif
 655             if( i_best_j >= 0 && i_best_i >= 0 )
 656             {
 657                 r_add( &region[i_best_i], &region[i_best_j] );
 658
 659                 if( i_best_j+1 < i_region )
 660                     memmove( &region[i_best_j], &region[i_best_j+1], sizeof(*region) * ( i_region - (i_best_j+1)  ) );
 661                 i_region--;
 662             }
 663         }
 664     }
 665
 666     /* */
 667     for( int n = 0; n < i_region; n++ )
 668         p_region[n] = region[n];
 669
 670 #ifdef DEBUG_REGION
 671     int64_t i_ck_time = mdate() - i_ck_start;
 672     msg_Err( p_spu, "ASS: %d objects merged into %d region in %d micros", i_count, i_region, (int)(i_ck_time) );
 673 #endif
 674
 675     free( pp_img );
 676
 677     return i_region;
 678 }
 679
 680 static void RegionDraw( subpicture_region_t *p_region, ASS_Image *p_img )
 681 {
 682     const plane_t *p = &p_region->p_picture->p[0];
 683     const int i_x = p_region->i_x;
 684     const int i_y = p_region->i_y;
 685     const int i_width  = p_region->fmt.i_width;
 686     const int i_height = p_region->fmt.i_height;
 687
 688     memset( p->p_pixels, 0x00, p->i_pitch * p->i_lines );
 689     for( ; p_img != NULL; p_img = p_img->next )
 690     {
 691         if( p_img->dst_x < i_x || p_img->dst_x + p_img->w > i_x + i_width ||
 692             p_img->dst_y < i_y || p_img->dst_y + p_img->h > i_y + i_height )
 693             continue;
 694
 695         const unsigned r = (p_img->color >> 24)&0xff;
 696         const unsigned g = (p_img->color >> 16)&0xff;
 697         const unsigned b = (p_img->color >>  8)&0xff;
 698         const unsigned a = (p_img->color      )&0xff;
 699         int x, y;
 700
 701         for( y = 0; y < p_img->h; y++ )
 702         {
 703             for( x = 0; x < p_img->w; x++ )
 704             {
 705                 const unsigned alpha = p_img->bitmap[y*p_img->stride+x];
 706                 const unsigned an = (255 - a) * alpha / 255;
 707
 708                 uint8_t *p_rgba = &p->p_pixels[(y+p_img->dst_y-i_y) * p->i_pitch + 4 * (x+p_img->dst_x-i_x)];
 709                 const unsigned ao = p_rgba[3];
 710
 711                 /* Native endianness, but RGBA ordering */
 712                 if( ao == 0 )
 713                 {
 714                     /* Optimized but the else{} will produce the same result */
 715                     p_rgba[0] = r;
 716                     p_rgba[1] = g;
 717                     p_rgba[2] = b;
 718                     p_rgba[3] = an;
 719                 }
 720                 else
 721                 {
 722                     p_rgba[3] = 255 - ( 255 - p_rgba[3] ) * ( 255 - an ) / 255;
 723                     if( p_rgba[3] != 0 )
 724                     {
 725                         p_rgba[0] = ( p_rgba[0] * ao * (255-an) / 255 + r * an ) / p_rgba[3];
 726                         p_rgba[1] = ( p_rgba[1] * ao * (255-an) / 255 + g * an ) / p_rgba[3];
 727                         p_rgba[2] = ( p_rgba[2] * ao * (255-an) / 255 + b * an ) / p_rgba[3];
 728                     }
 729                 }
 730             }
 731         }
 732     }
 733
 734 #ifdef DEBUG_REGION
 735     /* XXX Draw a box for debug */
 736 #define P(x,y) ((uint32_t*)&p->p_pixels[(y)*p->i_pitch + 4*(x)])
 737     for( int y = 0; y < p->i_lines; y++ )
 738         *P(0,y) = *P(p->i_visible_pitch/4-1,y) = 0xff000000;
 739     for( int x = 0; x < p->i_visible_pitch; x++ )
 740         *P(x/4,0) = *P(x/4,p->i_visible_lines-1) = 0xff000000;
 741 #undef P
 742 #endif
 743 }
 744