research.m1stereo.tv/gitweb/ - melted/blob - src/modules/gtk2/producer_pango.c

   1 /*
   2  * producer_pango.c -- a pango-based titler
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Dan Dennedy <dan@dennedy.org>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library 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 GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include <framework/mlt_producer.h>
  22 #include <framework/mlt_frame.h>
  23 #include <framework/mlt_geometry.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <gdk-pixbuf/gdk-pixbuf.h>
  27 #include <pango/pangoft2.h>
  28 #include <freetype/freetype.h>
  29 #include <iconv.h>
  30 #include <pthread.h>
  31 #include <ctype.h>
  32
  33 typedef struct producer_pango_s *producer_pango;
  34
  35 typedef enum
  36 {
  37         pango_align_left = 0,
  38         pango_align_center,
  39         pango_align_right
  40 } pango_align;
  41
  42 static pthread_mutex_t pango_mutex = PTHREAD_MUTEX_INITIALIZER;
  43
  44 struct producer_pango_s
  45 {
  46         struct mlt_producer_s parent;
  47         int width;
  48         int height;
  49         uint8_t *image;
  50         uint8_t *alpha;
  51         char *fgcolor;
  52         char *bgcolor;
  53         int   align;
  54         int   pad;
  55         char *markup;
  56         char *text;
  57         char *font;
  58         int weight;
  59 };
  60
  61 // special color type used by internal pango routines
  62 typedef struct
  63 {
  64         uint8_t r, g, b, a;
  65 } rgba_color;
  66
  67 // Forward declarations
  68 static int producer_get_frame( mlt_producer parent, mlt_frame_ptr frame, int index );
  69 static void producer_close( mlt_producer parent );
  70 static void pango_draw_background( GdkPixbuf *pixbuf, rgba_color bg );
  71 static GdkPixbuf *pango_get_pixbuf( const char *markup, const char *text, const char *font,
  72         rgba_color fg, rgba_color bg, int pad, int align, int weight, int size );
  73
  74 /** Return nonzero if the two strings are equal, ignoring case, up to
  75     the first n characters.
  76 */
  77 int strncaseeq(const char *s1, const char *s2, size_t n)
  78 {
  79         for ( ; n > 0; n--)
  80         {
  81                 if (tolower(*s1++) != tolower(*s2++))
  82                         return 0;
  83         }
  84         return 1;
  85 }
  86
  87 /** Parse the alignment property.
  88 */
  89
  90 static int alignment_parse( char* align )
  91 {
  92         int ret = pango_align_left;
  93
  94         if ( align == NULL );
  95         else if ( isdigit( align[ 0 ] ) )
  96                 ret = atoi( align );
  97         else if ( align[ 0 ] == 'c' || align[ 0 ] == 'm' )
  98                 ret = pango_align_center;
  99         else if ( align[ 0 ] == 'r' )
 100                 ret = pango_align_right;
 101
 102         return ret;
 103 }
 104
 105 static PangoFT2FontMap *fontmap = NULL;
 106
 107 mlt_producer producer_pango_init( const char *filename )
 108 {
 109         producer_pango this = calloc( sizeof( struct producer_pango_s ), 1 );
 110         if ( this != NULL && mlt_producer_init( &this->parent, this ) == 0 )
 111         {
 112                 mlt_producer producer = &this->parent;
 113
 114                 pthread_mutex_lock( &pango_mutex );
 115                 if ( fontmap == NULL )
 116                         fontmap = (PangoFT2FontMap*) pango_ft2_font_map_new();
 117                 g_type_init();
 118                 pthread_mutex_unlock( &pango_mutex );
 119
 120                 producer->get_frame = producer_get_frame;
 121                 producer->close = ( mlt_destructor )producer_close;
 122
 123                 // Get the properties interface
 124                 mlt_properties properties = MLT_PRODUCER_PROPERTIES( &this->parent );
 125
 126                 // Set the default properties
 127                 mlt_properties_set( properties, "fgcolour", "0xffffffff" );
 128                 mlt_properties_set( properties, "bgcolour", "0x00000000" );
 129                 mlt_properties_set_int( properties, "align", pango_align_left );
 130                 mlt_properties_set_int( properties, "pad", 0 );
 131                 mlt_properties_set( properties, "text", "" );
 132                 mlt_properties_set( properties, "font", "Sans 48" );
 133                 mlt_properties_set( properties, "encoding", "UTF-8" );
 134                 mlt_properties_set_int( properties, "weight", PANGO_WEIGHT_NORMAL );
 135
 136                 if ( filename == NULL )
 137                 {
 138                         mlt_properties_set( properties, "markup", "" );
 139                 }
 140                 else if ( filename[ 0 ] == '+' || strstr( filename, "/+" ) )
 141                 {
 142                         char *copy = strdup( filename + 1 );
 143                         char *markup = copy;
 144                         if ( strstr( markup, "/+" ) )
 145                                 markup = strstr( markup, "/+" ) + 2;
 146                         ( *strrchr( markup, '.' ) ) = '\0';
 147                         while ( strchr( markup, '~' ) )
 148                                 ( *strchr( markup, '~' ) ) = '\n';
 149                         mlt_properties_set( properties, "resource", filename );
 150                         mlt_properties_set( properties, "markup", markup );
 151                         free( copy );
 152                 }
 153                 else if ( strstr( filename, ".mpl" ) )
 154                 {
 155                         int i = 0;
 156                         mlt_properties contents = mlt_properties_load( filename );
 157                         mlt_geometry key_frames = mlt_geometry_init( );
 158                         struct mlt_geometry_item_s item;
 159                         mlt_properties_set( properties, "resource", filename );
 160                         mlt_properties_set_data( properties, "contents", contents, 0, ( mlt_destructor )mlt_properties_close, NULL );
 161                         mlt_properties_set_data( properties, "key_frames", key_frames, 0, ( mlt_destructor )mlt_geometry_close, NULL );
 162
 163                         // Make sure we have at least one entry
 164                         if ( mlt_properties_get( contents, "0" ) == NULL )
 165                                 mlt_properties_set( contents, "0", "" );
 166
 167                         for ( i = 0; i < mlt_properties_count( contents ); i ++ )
 168                         {
 169                                 char *name = mlt_properties_get_name( contents, i );
 170                                 char *value = mlt_properties_get_value( contents, i );
 171                                 while ( value != NULL && strchr( value, '~' ) )
 172                                         ( *strchr( value, '~' ) ) = '\n';
 173                                 item.frame = atoi( name );
 174                                 mlt_geometry_insert( key_frames, &item );
 175                         }
 176                 }
 177                 else
 178                 {
 179                         FILE *f = fopen( filename, "r" );
 180                         if ( f != NULL )
 181                         {
 182                                 char line[81];
 183                                 char *markup = NULL;
 184                                 size_t size = 0;
 185                                 line[80] = '\0';
 186
 187                                 while ( fgets( line, 80, f ) )
 188                                 {
 189                                         size += strlen( line ) + 1;
 190                                         if ( markup )
 191                                         {
 192                                                 markup = realloc( markup, size );
 193                                                 strcat( markup, line );
 194                                         }
 195                                         else
 196                                         {
 197                                                 markup = strdup( line );
 198                                         }
 199                                 }
 200                                 fclose( f );
 201
 202                                 if ( markup[ strlen( markup ) - 1 ] == '\n' )
 203                                         markup[ strlen( markup ) - 1 ] = '\0';
 204
 205                                 mlt_properties_set( properties, "resource", filename );
 206                                 mlt_properties_set( properties, "markup", ( markup == NULL ? "" : markup ) );
 207                                 free( markup );
 208                         }
 209                         else
 210                         {
 211                                 mlt_properties_set( properties, "markup", "" );
 212                         }
 213                 }
 214
 215                 return producer;
 216         }
 217         free( this );
 218         return NULL;
 219 }
 220
 221 static void set_string( char **string, char *value, char *fallback )
 222 {
 223         if ( value != NULL )
 224         {
 225                 free( *string );
 226                 *string = strdup( value );
 227         }
 228         else if ( *string == NULL && fallback != NULL )
 229         {
 230                 *string = strdup( fallback );
 231         }
 232         else if ( *string != NULL && fallback == NULL )
 233         {
 234                 free( *string );
 235                 *string = NULL;
 236         }
 237 }
 238
 239 rgba_color parse_color( char *color )
 240 {
 241         rgba_color result = { 0xff, 0xff, 0xff, 0xff };
 242
 243         if ( !strncmp( color, "0x", 2 ) )
 244         {
 245                 unsigned int temp = 0;
 246                 sscanf( color + 2, "%x", &temp );
 247                 result.r = ( temp >> 24 ) & 0xff;
 248                 result.g = ( temp >> 16 ) & 0xff;
 249                 result.b = ( temp >> 8 ) & 0xff;
 250                 result.a = ( temp ) & 0xff;
 251         }
 252         else if ( !strcmp( color, "red" ) )
 253         {
 254                 result.r = 0xff;
 255                 result.g = 0x00;
 256                 result.b = 0x00;
 257         }
 258         else if ( !strcmp( color, "green" ) )
 259         {
 260                 result.r = 0x00;
 261                 result.g = 0xff;
 262                 result.b = 0x00;
 263         }
 264         else if ( !strcmp( color, "blue" ) )
 265         {
 266                 result.r = 0x00;
 267                 result.g = 0x00;
 268                 result.b = 0xff;
 269         }
 270         else
 271         {
 272                 unsigned int temp = 0;
 273                 sscanf( color, "%d", &temp );
 274                 result.r = ( temp >> 24 ) & 0xff;
 275                 result.g = ( temp >> 16 ) & 0xff;
 276                 result.b = ( temp >> 8 ) & 0xff;
 277                 result.a = ( temp ) & 0xff;
 278         }
 279
 280         return result;
 281 }
 282
 283 /** Convert a string property to UTF-8
 284 */
 285 static int iconv_utf8( mlt_properties properties, char *prop_name, const char* encoding )
 286 {
 287         char *text = mlt_properties_get( properties, prop_name );
 288         int result = -1;
 289
 290         iconv_t cd = iconv_open( "UTF-8", encoding );
 291         if ( cd != ( iconv_t )-1 )
 292         {
 293                 char *inbuf_p = text;
 294                 size_t inbuf_n = strlen( text );
 295                 size_t outbuf_n = inbuf_n * 6;
 296                 char *outbuf = mlt_pool_alloc( outbuf_n );
 297                 char *outbuf_p = outbuf;
 298
 299                 memset( outbuf, 0, outbuf_n );
 300
 301                 if ( text != NULL && strcmp( text, "" ) && iconv( cd, &inbuf_p, &inbuf_n, &outbuf_p, &outbuf_n ) != -1 )
 302                         mlt_properties_set( properties, prop_name, outbuf );
 303                 else
 304                         mlt_properties_set( properties, prop_name, "" );
 305
 306                 mlt_pool_release( outbuf );
 307                 iconv_close( cd );
 308                 result = 0;
 309         }
 310         return result;
 311 }
 312
 313 static void refresh_image( mlt_frame frame, int width, int height )
 314 {
 315         // Pixbuf
 316         GdkPixbuf *pixbuf = mlt_properties_get_data( MLT_FRAME_PROPERTIES( frame ), "pixbuf", NULL );
 317
 318         // Obtain properties of frame
 319         mlt_properties properties = MLT_FRAME_PROPERTIES( frame );
 320
 321         // Obtain the producer pango for this frame
 322         producer_pango this = mlt_properties_get_data( properties, "producer_pango", NULL );
 323
 324         // Obtain the producer
 325         mlt_producer producer = &this->parent;
 326
 327         // Obtain the producer properties
 328         mlt_properties producer_props = MLT_PRODUCER_PROPERTIES( producer );
 329
 330         // Get producer properties
 331         char *fg = mlt_properties_get( producer_props, "fgcolour" );
 332         char *bg = mlt_properties_get( producer_props, "bgcolour" );
 333         int align = alignment_parse( mlt_properties_get( producer_props, "align" ) );
 334         int pad = mlt_properties_get_int( producer_props, "pad" );
 335         char *markup = mlt_properties_get( producer_props, "markup" );
 336         char *text = mlt_properties_get( producer_props, "text" );
 337         char *font = mlt_properties_get( producer_props, "font" );
 338         char *encoding = mlt_properties_get( producer_props, "encoding" );
 339         int weight = mlt_properties_get_int( producer_props, "weight" );
 340         int size = mlt_properties_get_int( producer_props, "size" );
 341         int property_changed = 0;
 342
 343         if ( pixbuf == NULL )
 344         {
 345                 // Check for file support
 346                 int position = mlt_properties_get_position( properties, "pango_position" );
 347                 mlt_properties contents = mlt_properties_get_data( producer_props, "contents", NULL );
 348                 mlt_geometry key_frames = mlt_properties_get_data( producer_props, "key_frames", NULL );
 349                 struct mlt_geometry_item_s item;
 350                 if ( contents != NULL )
 351                 {
 352                         char temp[ 20 ];
 353                         mlt_geometry_prev_key( key_frames, &item, position );
 354                         sprintf( temp, "%d", item.frame );
 355                         markup = mlt_properties_get( contents, temp );
 356                 }
 357
 358                 // See if any properties changed
 359                 property_changed = ( align != this->align );
 360                 property_changed = property_changed || ( this->fgcolor == NULL || ( fg && strcmp( fg, this->fgcolor ) ) );
 361                 property_changed = property_changed || ( this->bgcolor == NULL || ( bg && strcmp( bg, this->bgcolor ) ) );
 362                 property_changed = property_changed || ( pad != this->pad );
 363                 property_changed = property_changed || ( markup && this->markup && strcmp( markup, this->markup ) );
 364                 property_changed = property_changed || ( text && this->text && strcmp( text, this->text ) );
 365                 property_changed = property_changed || ( font && this->font && strcmp( font, this->font ) );
 366                 property_changed = property_changed || ( weight != this->weight );
 367
 368                 // Save the properties for next comparison
 369                 this->align = align;
 370                 this->pad = pad;
 371                 set_string( &this->fgcolor, fg, "0xffffffff" );
 372                 set_string( &this->bgcolor, bg, "0x00000000" );
 373                 set_string( &this->markup, markup, NULL );
 374                 set_string( &this->text, text, NULL );
 375                 set_string( &this->font, font, "Sans 48" );
 376                 this->weight = weight;
 377         }
 378
 379         if ( pixbuf == NULL && property_changed )
 380         {
 381                 rgba_color fgcolor = parse_color( this->fgcolor );
 382                 rgba_color bgcolor = parse_color( this->bgcolor );
 383
 384                 mlt_pool_release( this->image );
 385                 mlt_pool_release( this->alpha );
 386                 this->image = NULL;
 387                 this->alpha = NULL;
 388
 389                 // Convert from specified encoding to UTF-8
 390                 if ( encoding != NULL && !strncaseeq( encoding, "utf-8", 5 ) && !strncaseeq( encoding, "utf8", 4 ) )
 391                 {
 392                         if ( markup != NULL && iconv_utf8( producer_props, "markup", encoding ) != -1 )
 393                         {
 394                                 markup = mlt_properties_get( producer_props, "markup" );
 395                                 set_string( &this->markup, markup, NULL );
 396                         }
 397                         if ( text != NULL && iconv_utf8( producer_props, "text", encoding ) != -1 )
 398                         {
 399                                 text = mlt_properties_get( producer_props, "text" );
 400                                 set_string( &this->text, text, NULL );
 401                         }
 402                 }
 403
 404                 // Render the title
 405                 pixbuf = pango_get_pixbuf( markup, text, font, fgcolor, bgcolor, pad, align, weight, size );
 406
 407                 if ( pixbuf != NULL )
 408                 {
 409                         // Register this pixbuf for destruction and reuse
 410                         mlt_properties_set_data( producer_props, "pixbuf", pixbuf, 0, ( mlt_destructor )g_object_unref, NULL );
 411                         g_object_ref( pixbuf );
 412                         mlt_properties_set_data( MLT_FRAME_PROPERTIES( frame ), "pixbuf", pixbuf, 0, ( mlt_destructor )g_object_unref, NULL );
 413
 414                         mlt_properties_set_int( producer_props, "real_width", gdk_pixbuf_get_width( pixbuf ) );
 415                         mlt_properties_set_int( producer_props, "real_height", gdk_pixbuf_get_height( pixbuf ) );
 416
 417                         // Store the width/height of the pixbuf temporarily
 418                         this->width = gdk_pixbuf_get_width( pixbuf );
 419                         this->height = gdk_pixbuf_get_height( pixbuf );
 420                 }
 421         }
 422         else if ( pixbuf == NULL && ( width > 0 && ( this->image == NULL || width != this->width || height != this->height ) ) )
 423         {
 424                 mlt_pool_release( this->image );
 425                 mlt_pool_release( this->alpha );
 426                 this->image = NULL;
 427                 this->alpha = NULL;
 428
 429                 pixbuf = mlt_properties_get_data( producer_props, "pixbuf", NULL );
 430         }
 431
 432         // If we have a pixbuf and a valid width
 433         if ( pixbuf && width > 0 )
 434         {
 435                 char *interps = mlt_properties_get( properties, "rescale.interp" );
 436                 int interp = GDK_INTERP_BILINEAR;
 437
 438                 if ( strcmp( interps, "nearest" ) == 0 )
 439                         interp = GDK_INTERP_NEAREST;
 440                 else if ( strcmp( interps, "tiles" ) == 0 )
 441                         interp = GDK_INTERP_TILES;
 442                 else if ( strcmp( interps, "hyper" ) == 0 )
 443                         interp = GDK_INTERP_HYPER;
 444
 445 // fprintf(stderr,"%s: scaling from %dx%d to %dx%d\n", __FILE__, this->width, this->height, width, height);
 446
 447                 // Note - the original pixbuf is already safe and ready for destruction
 448                 pixbuf = gdk_pixbuf_scale_simple( pixbuf, width, height, interp );
 449
 450                 // Store width and height
 451                 this->width = width;
 452                 this->height = height;
 453
 454                 // Allocate/define image
 455                 this->image = mlt_pool_alloc( width * ( height + 1 ) * 2 );
 456                 this->alpha = mlt_pool_alloc( this->width * this->height );
 457
 458                 // Convert the image
 459                 mlt_convert_rgb24a_to_yuv422( gdk_pixbuf_get_pixels( pixbuf ),
 460                                                                           this->width, this->height,
 461                                                                           gdk_pixbuf_get_rowstride( pixbuf ),
 462                                                                           this->image, this->alpha );
 463
 464                 // Finished with pixbuf now
 465                 g_object_unref( pixbuf );
 466         }
 467
 468         // Set width/height
 469         mlt_properties_set_int( properties, "width", this->width );
 470         mlt_properties_set_int( properties, "height", this->height );
 471         mlt_properties_set_int( properties, "real_width", mlt_properties_get_int( producer_props, "real_width" ) );
 472         mlt_properties_set_int( properties, "real_height", mlt_properties_get_int( producer_props, "real_height" ) );
 473
 474         // pass the image data without destructor
 475         mlt_properties_set_data( properties, "image", this->image, this->width * ( this->height + 1 ) * 2, NULL, NULL );
 476         mlt_properties_set_data( properties, "alpha", this->alpha, this->width * this->height, NULL, NULL );
 477 }
 478
 479 static int producer_get_image( mlt_frame frame, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
 480 {
 481         // Obtain properties of frame
 482         mlt_properties properties = MLT_FRAME_PROPERTIES( frame );
 483
 484         // We need to know the size of the image to clone it
 485         int image_size = 0;
 486         int alpha_size = 0;
 487
 488         // Alpha channel
 489         uint8_t *alpha = NULL;
 490
 491         *width = mlt_properties_get_int( properties, "rescale_width" );
 492         *height = mlt_properties_get_int( properties, "rescale_height" );
 493
 494         // Refresh the image
 495         pthread_mutex_lock( &pango_mutex );
 496         refresh_image( frame, *width, *height );
 497
 498         // Get the image
 499         *buffer = mlt_properties_get_data( properties, "image", &image_size );
 500         alpha = mlt_properties_get_data( properties, "alpha", &alpha_size );
 501
 502         // Get width and height
 503         *width = mlt_properties_get_int( properties, "width" );
 504         *height = mlt_properties_get_int( properties, "height" );
 505
 506         // Always clone here to allow 'animated' text
 507         if ( *buffer != NULL )
 508         {
 509                 // Clone the image and the alpha
 510                 uint8_t *image_copy = mlt_pool_alloc( image_size );
 511                 uint8_t *alpha_copy = mlt_pool_alloc( alpha_size );
 512
 513                 memcpy( image_copy, *buffer, image_size );
 514
 515                 // Copy or default the alpha
 516                 if ( alpha != NULL )
 517                         memcpy( alpha_copy, alpha, alpha_size );
 518                 else
 519                         memset( alpha_copy, 255, alpha_size );
 520
 521                 // Now update properties so we free the copy after
 522                 mlt_properties_set_data( properties, "image", image_copy, image_size, mlt_pool_release, NULL );
 523                 mlt_properties_set_data( properties, "alpha", alpha_copy, alpha_size, mlt_pool_release, NULL );
 524
 525                 // We're going to pass the copy on
 526                 *buffer = image_copy;
 527         }
 528         else
 529         {
 530                 // TODO: Review all cases of invalid images
 531                 *buffer = mlt_pool_alloc( 50 * 50 * 2 );
 532                 mlt_properties_set_data( properties, "image", *buffer, image_size, mlt_pool_release, NULL );
 533                 *width = 50;
 534                 *height = 50;
 535         }
 536
 537         pthread_mutex_unlock( &pango_mutex );
 538
 539         return 0;
 540 }
 541
 542 static uint8_t *producer_get_alpha_mask( mlt_frame this )
 543 {
 544         // Obtain properties of frame
 545         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
 546
 547         // Return the alpha mask
 548         return mlt_properties_get_data( properties, "alpha", NULL );
 549 }
 550
 551 static int producer_get_frame( mlt_producer producer, mlt_frame_ptr frame, int index )
 552 {
 553         producer_pango this = producer->child;
 554
 555         // Generate a frame
 556         *frame = mlt_frame_init( MLT_PRODUCER_SERVICE( producer ) );
 557
 558         // Obtain properties of frame and producer
 559         mlt_properties properties = MLT_FRAME_PROPERTIES( *frame );
 560
 561         // Set the producer on the frame properties
 562         mlt_properties_set_data( properties, "producer_pango", this, 0, NULL, NULL );
 563
 564         // Update timecode on the frame we're creating
 565         mlt_frame_set_position( *frame, mlt_producer_position( producer ) );
 566         mlt_properties_set_position( properties, "pango_position", mlt_producer_frame( producer ) );
 567
 568         // Refresh the pango image
 569         pthread_mutex_lock( &pango_mutex );
 570         refresh_image( *frame, 0, 0 );
 571         pthread_mutex_unlock( &pango_mutex );
 572
 573         // Set producer-specific frame properties
 574         mlt_properties_set_int( properties, "progressive", 1 );
 575         mlt_properties_set_double( properties, "aspect_ratio", 1 );
 576
 577         // Set alpha call back
 578         ( *frame )->get_alpha_mask = producer_get_alpha_mask;
 579
 580         // Stack the get image callback
 581         mlt_frame_push_get_image( *frame, producer_get_image );
 582
 583         // Calculate the next timecode
 584         mlt_producer_prepare_next( producer );
 585
 586         return 0;
 587 }
 588
 589 static void producer_close( mlt_producer parent )
 590 {
 591         producer_pango this = parent->child;
 592         mlt_pool_release( this->image );
 593         mlt_pool_release( this->alpha );
 594         free( this->fgcolor );
 595         free( this->bgcolor );
 596         free( this->markup );
 597         free( this->text );
 598         free( this->font );
 599         parent->close = NULL;
 600         mlt_producer_close( parent );
 601         free( this );
 602 }
 603
 604 static void pango_draw_background( GdkPixbuf *pixbuf, rgba_color bg )
 605 {
 606         int ww = gdk_pixbuf_get_width( pixbuf );
 607         int hh = gdk_pixbuf_get_height( pixbuf );
 608         uint8_t *p = gdk_pixbuf_get_pixels( pixbuf );
 609         int i, j;
 610
 611         for ( j = 0; j < hh; j++ )
 612         {
 613                 for ( i = 0; i < ww; i++ )
 614                 {
 615                         *p++ = bg.r;
 616                         *p++ = bg.g;
 617                         *p++ = bg.b;
 618                         *p++ = bg.a;
 619                 }
 620         }
 621 }
 622
 623 static GdkPixbuf *pango_get_pixbuf( const char *markup, const char *text, const char *font, rgba_color fg, rgba_color bg, int pad, int align, int weight, int size )
 624 {
 625         PangoContext *context = pango_ft2_font_map_create_context( fontmap );
 626         PangoLayout *layout = pango_layout_new( context );
 627         int w, h, x;
 628         int i, j;
 629         GdkPixbuf *pixbuf = NULL;
 630         FT_Bitmap bitmap;
 631         uint8_t *src = NULL;
 632         uint8_t* dest = NULL;
 633         uint8_t *d, *s, a;
 634         int stride;
 635         PangoFontDescription *desc = pango_font_description_from_string( font );
 636
 637         pango_ft2_font_map_set_resolution( fontmap, 72, 72 );
 638         pango_layout_set_width( layout, -1 ); // set wrapping constraints
 639         pango_font_description_set_weight( desc, ( PangoWeight ) weight  );
 640         if ( size != 0 )
 641                 pango_font_description_set_absolute_size( desc, PANGO_SCALE * size );
 642         pango_layout_set_font_description( layout, desc );
 643 //      pango_layout_set_spacing( layout, space );
 644         pango_layout_set_alignment( layout, ( PangoAlignment ) align  );
 645         if ( markup != NULL && strcmp( markup, "" ) != 0 )
 646         {
 647                 pango_layout_set_markup( layout, markup, strlen( markup ) );
 648         }
 649         else if ( text != NULL && strcmp( text, "" ) != 0 )
 650         {
 651                 // Replace all ~'s with a line feed (silly convention, but handy)
 652                 char *copy = strdup( text );
 653                 while ( strchr( copy, '~' ) )
 654                         ( *strchr( copy, '~' ) ) = '\n';
 655                 pango_layout_set_text( layout, copy, strlen( copy ) );
 656                 free( copy );
 657         }
 658         else
 659         {
 660                 // Pango doesn't like empty strings
 661                 pango_layout_set_text( layout, "  ", 2 );
 662         }
 663         pango_layout_get_pixel_size( layout, &w, &h );
 664
 665         // Interpret size property as an absolute pixel height and compensate for
 666         // freetype's "interpretation" of our absolute size request. This gives
 667         // precise control over compositing and better quality by reducing scaling
 668         // artifacts with composite geometries that constrain the dimensions.
 669         // If you do not want this, then put the size in the font property or in
 670         // the pango markup.
 671         if ( size != 0 )
 672         {
 673                 pango_font_description_set_absolute_size( desc, PANGO_SCALE * size * size/h );
 674                 pango_layout_set_font_description( layout, desc );
 675                 pango_layout_get_pixel_size( layout, &w, &h );
 676         }
 677
 678         pixbuf = gdk_pixbuf_new( GDK_COLORSPACE_RGB, TRUE /* has alpha */, 8, w + 2 * pad, h + 2 * pad );
 679         pango_draw_background( pixbuf, bg );
 680
 681         stride = gdk_pixbuf_get_rowstride( pixbuf );
 682
 683         bitmap.width     = w;
 684         bitmap.pitch     = 32 * ( ( w + 31 ) / 31 );
 685         bitmap.rows      = h;
 686         bitmap.buffer    = mlt_pool_alloc( h * bitmap.pitch );
 687         bitmap.num_grays = 256;
 688         bitmap.pixel_mode = ft_pixel_mode_grays;
 689
 690         memset( bitmap.buffer, 0, h * bitmap.pitch );
 691
 692         pango_ft2_render_layout( &bitmap, layout, 0, 0 );
 693
 694         src = bitmap.buffer;
 695         x = ( gdk_pixbuf_get_width( pixbuf ) - w - 2 * pad ) * align / 2 + pad;
 696         dest = gdk_pixbuf_get_pixels( pixbuf ) + 4 * x + pad * stride;
 697         j = h;
 698
 699         while( j -- )
 700         {
 701                 d = dest;
 702                 s = src;
 703                 i = w;
 704                 while( i -- )
 705                 {
 706                         a = *s ++;
 707                         *d++ = ( a * fg.r + ( 255 - a ) * bg.r ) >> 8;
 708                         *d++ = ( a * fg.g + ( 255 - a ) * bg.g ) >> 8;
 709                         *d++ = ( a * fg.b + ( 255 - a ) * bg.b ) >> 8;
 710                         *d++ = ( a * fg.a + ( 255 - a ) * bg.a ) >> 8;
 711                 }
 712                 dest += stride;
 713                 src += bitmap.pitch;
 714         }
 715         mlt_pool_release( bitmap.buffer );
 716         pango_font_description_free( desc );
 717         g_object_unref( layout );
 718         g_object_unref( context );
 719
 720         return pixbuf;
 721 }