modules/codec/zvbi.c

   1 /*****************************************************************************
   2  * zvbi.c : VBI and Teletext PES demux and decoder using libzvbi
   3  *****************************************************************************
   4  * Copyright (C) 2007, M2X
   5  * $Id$
   6  *
   7  * Authors: Derk-Jan Hartman <djhartman at m2x dot nl>
   8  *          Jean-Paul Saman <jpsaman at m2x dot nl>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24 /*****************************************************************************
  25  *
  26  * information on teletext format can be found here :
  27  * http://pdc.ro.nu/teletext.html
  28  *
  29  *****************************************************************************/
  30
  31 /* This module implements:
  32  * ETSI EN 301 775: VBI data in PES
  33  * ETSI EN 300 472: EBU Teletext data in PES
  34  * ETSI EN 300 706: Enhanced Teletext (libzvbi)
  35  * ETSI EN 300 231: Video Programme System [VPS] (libzvbi)
  36  * ETSI EN 300 294: 625-line Wide Screen Signaling [WSS] (libzvbi)
  37  * EIA-608 Revision A: Closed Captioning [CC] (libzvbi)
  38  */
  39
  40 #ifdef HAVE_CONFIG_H
  41 # include "config.h"
  42 #endif
  43
  44 #include <vlc_common.h>
  45 #include <vlc_plugin.h>
  46 #include <assert.h>
  47 #include <libzvbi.h>
  48
  49 #include <vlc_codec.h>
  50
  51 /*****************************************************************************
  52  * Module descriptor.
  53  *****************************************************************************/
  54 static int  Open ( vlc_object_t * );
  55 static void Close( vlc_object_t * );
  56
  57 #define PAGE_TEXT N_("Teletext page")
  58 #define PAGE_LONGTEXT N_("Open the indicated Teletext page." \
  59         "Default page is index 100")
  60
  61 #define OPAQUE_TEXT N_("Teletext transparency")
  62 #define OPAQUE_LONGTEXT N_("Setting vbi-opaque to false " \
  63         "makes the boxed text transparent." )
  64
  65 #define POS_TEXT N_("Teletext alignment")
  66 #define POS_LONGTEXT N_( \
  67   "You can enforce the teletext position on the video " \
  68   "(0=center, 1=left, 2=right, 4=top, 8=bottom, you can " \
  69   "also use combinations of these values, eg. 6 = top-right).")
  70
  71 #define TELX_TEXT N_("Teletext text subtitles")
  72 #define TELX_LONGTEXT N_( "Output teletext subtitles as text " \
  73   "instead of as RGBA" )
  74
  75 static const int pi_pos_values[] = { 0, 1, 2, 4, 8, 5, 6, 9, 10 };
  76 static const char *const ppsz_pos_descriptions[] =
  77 { N_("Center"), N_("Left"), N_("Right"), N_("Top"), N_("Bottom"),
  78   N_("Top-Left"), N_("Top-Right"), N_("Bottom-Left"), N_("Bottom-Right") };
  79
  80 vlc_module_begin ()
  81     set_description( N_("VBI and Teletext decoder") )
  82     set_shortname( N_("VBI & Teletext") )
  83     set_capability( "decoder", 51 )
  84     set_category( CAT_INPUT )
  85     set_subcategory( SUBCAT_INPUT_SCODEC )
  86     set_callbacks( Open, Close )
  87
  88     add_integer( "vbi-page", 100,
  89                  PAGE_TEXT, PAGE_LONGTEXT, false )
  90     add_bool( "vbi-opaque", true,
  91                  OPAQUE_TEXT, OPAQUE_LONGTEXT, false )
  92     add_integer( "vbi-position", 4, POS_TEXT, POS_LONGTEXT, false )
  93         change_integer_list( pi_pos_values, ppsz_pos_descriptions );
  94     add_bool( "vbi-text", false,
  95               TELX_TEXT, TELX_LONGTEXT, false )
  96 vlc_module_end ()
  97
  98 /****************************************************************************
  99  * Local structures
 100  ****************************************************************************/
 101
 102 // #define ZVBI_DEBUG
 103
 104 //Guessing table for missing "default region triplet"
 105 static const int pi_default_triplet[] = {
 106  0, 0,           // slo cze
 107  8,              // pol
 108  24,24,24,24,    //ssc scr slv rum
 109  32,32,32,32,32, //est lit rus bul ukr
 110  48,48,          //gre ell
 111  64,             //ara
 112  88,             //heb
 113  16 };           //default
 114 static const char *const ppsz_default_triplet[] = {
 115  "slo", "cze",
 116  "pol",
 117  "ssc", "scr", "slv", "rum",
 118  "est", "lit", "rus", "bul", "ukr",
 119  "gre", "ell",
 120  "ara",
 121  "heb",
 122  NULL
 123 };
 124
 125 typedef enum {
 126     ZVBI_KEY_RED    = 'r' << 16,
 127     ZVBI_KEY_GREEN  = 'g' << 16,
 128     ZVBI_KEY_YELLOW = 'y' << 16,
 129     ZVBI_KEY_BLUE   = 'b' << 16,
 130     ZVBI_KEY_INDEX  = 'i' << 16,
 131 } ttxt_key_id;
 132
 133 typedef enum {
 134     DATA_UNIT_EBU_TELETEXT_NON_SUBTITLE     = 0x02,
 135     DATA_UNIT_EBU_TELETEXT_SUBTITLE         = 0x03,
 136     DATA_UNIT_EBU_TELETEXT_INVERTED         = 0x0C,
 137
 138     DATA_UNIT_ZVBI_WSS_CPR1204              = 0xB4,
 139     DATA_UNIT_ZVBI_CLOSED_CAPTION_525       = 0xB5,
 140     DATA_UNIT_ZVBI_MONOCHROME_SAMPLES_525   = 0xB6,
 141
 142     DATA_UNIT_VPS                           = 0xC3,
 143     DATA_UNIT_WSS                           = 0xC4,
 144     DATA_UNIT_CLOSED_CAPTION                = 0xC5,
 145     DATA_UNIT_MONOCHROME_SAMPLES            = 0xC6,
 146
 147     DATA_UNIT_STUFFING                      = 0xFF,
 148 } data_unit_id;
 149
 150 struct decoder_sys_t
 151 {
 152     vbi_decoder *     p_vbi_dec;
 153     vbi_dvb_demux *   p_dvb_demux;
 154     unsigned int      i_last_page;
 155     bool              b_update;
 156     bool              b_text;   /* Subtitles as text */
 157
 158     vlc_mutex_t       lock; /* Lock to protect the following variables */
 159     /* Positioning of Teletext images */
 160     int               i_align;
 161     /* */
 162     unsigned int      i_wanted_page;
 163     unsigned int      i_wanted_subpage;
 164     /* */
 165     bool              b_opaque;
 166     struct {
 167         int pgno, subno;
 168     }                 nav_link[6];
 169     int               i_key[3];
 170 };
 171
 172 static subpicture_t *Decode( decoder_t *, block_t ** );
 173
 174 static subpicture_t *Subpicture( decoder_t *p_dec, video_format_t *p_fmt,
 175                                  bool b_text,
 176                                  int i_columns, int i_rows,
 177                                  int i_align, mtime_t i_pts );
 178
 179 static void EventHandler( vbi_event *ev, void *user_data );
 180 static int OpaquePage( picture_t *p_src, const vbi_page p_page,
 181                        const video_format_t fmt, bool b_opaque );
 182
 183 /* Properties callbacks */
 184 static int RequestPage( vlc_object_t *p_this, char const *psz_cmd,
 185                         vlc_value_t oldval, vlc_value_t newval, void *p_data );
 186 static int Opaque( vlc_object_t *p_this, char const *psz_cmd,
 187                    vlc_value_t oldval, vlc_value_t newval, void *p_data );
 188 static int Position( vlc_object_t *p_this, char const *psz_cmd,
 189                      vlc_value_t oldval, vlc_value_t newval, void *p_data );
 190 static int EventKey( vlc_object_t *p_this, char const *psz_cmd,
 191                      vlc_value_t oldval, vlc_value_t newval, void *p_data );
 192
 193 /*****************************************************************************
 194  * Open: probe the decoder and return score
 195  *****************************************************************************
 196  * Tries to launch a decoder and return score so that the interface is able
 197  * to chose.
 198  *****************************************************************************/
 199 static int Open( vlc_object_t *p_this )
 200 {
 201     decoder_t     *p_dec = (decoder_t *) p_this;
 202     decoder_sys_t *p_sys = NULL;
 203
 204     if( p_dec->fmt_in.i_codec != VLC_CODEC_TELETEXT )
 205         return VLC_EGENERIC;
 206
 207     p_dec->pf_decode_sub = Decode;
 208     p_sys = p_dec->p_sys = calloc( 1, sizeof(decoder_sys_t) );
 209     if( p_sys == NULL )
 210         return VLC_ENOMEM;
 211
 212     p_sys->i_key[0] = p_sys->i_key[1] = p_sys->i_key[2] = '*' - '0';
 213     p_sys->b_update = false;
 214     p_sys->p_vbi_dec = vbi_decoder_new();
 215     p_sys->p_dvb_demux = vbi_dvb_pes_demux_new( NULL, NULL );
 216     vlc_mutex_init( &p_sys->lock );
 217
 218     if( (p_sys->p_vbi_dec == NULL) || (p_sys->p_dvb_demux == NULL) )
 219     {
 220         msg_Err( p_dec, "VBI decoder/demux could not be created." );
 221         Close( p_this );
 222         return VLC_ENOMEM;
 223     }
 224
 225     /* Some broadcasters in countries with level 1 and level 1.5 still not send a G0 to do
 226      * matches against table 32 of ETSI 300 706. We try to do some best effort guessing
 227      * This is not perfect, but might handle some cases where we know the vbi language
 228      * is known. It would be better if people started sending G0 */
 229     for( int i = 0; ppsz_default_triplet[i] != NULL; i++ )
 230     {
 231         if( p_dec->fmt_in.psz_language && !strcasecmp( p_dec->fmt_in.psz_language, ppsz_default_triplet[i] ) )
 232         {
 233             vbi_teletext_set_default_region( p_sys->p_vbi_dec, pi_default_triplet[i]);
 234             msg_Dbg( p_dec, "overwriting default zvbi region: %d", pi_default_triplet[i] );
 235         }
 236     }
 237
 238     vbi_event_handler_register( p_sys->p_vbi_dec, VBI_EVENT_TTX_PAGE | VBI_EVENT_NETWORK |
 239 #ifdef ZVBI_DEBUG
 240                                 VBI_EVENT_CAPTION | VBI_EVENT_TRIGGER |
 241                                 VBI_EVENT_ASPECT | VBI_EVENT_PROG_INFO | VBI_EVENT_NETWORK_ID |
 242 #endif
 243                                 0 , EventHandler, p_dec );
 244
 245     /* Create the var on vlc_global. */
 246     p_sys->i_wanted_page = var_CreateGetInteger( p_dec, "vbi-page" );
 247     var_AddCallback( p_dec, "vbi-page", RequestPage, p_sys );
 248
 249     /* Check if the Teletext track has a known "initial page". */
 250     if( p_sys->i_wanted_page == 100 && p_dec->fmt_in.subs.teletext.i_magazine != -1 )
 251     {
 252         p_sys->i_wanted_page = 100 * p_dec->fmt_in.subs.teletext.i_magazine +
 253                                vbi_bcd2dec( p_dec->fmt_in.subs.teletext.i_page );
 254         var_SetInteger( p_dec, "vbi-page", p_sys->i_wanted_page );
 255     }
 256     p_sys->i_wanted_subpage = VBI_ANY_SUBNO;
 257
 258     p_sys->b_opaque = var_CreateGetBool( p_dec, "vbi-opaque" );
 259     var_AddCallback( p_dec, "vbi-opaque", Opaque, p_sys );
 260
 261     p_sys->i_align = var_CreateGetInteger( p_dec, "vbi-position" );
 262     var_AddCallback( p_dec, "vbi-position", Position, p_sys );
 263
 264     p_sys->b_text = var_CreateGetBool( p_dec, "vbi-text" );
 265 //    var_AddCallback( p_dec, "vbi-text", Text, p_sys );
 266
 267     /* Listen for keys */
 268     var_AddCallback( p_dec->p_libvlc, "key-pressed", EventKey, p_dec );
 269
 270     es_format_Init( &p_dec->fmt_out, SPU_ES, VLC_CODEC_SPU );
 271     if( p_sys->b_text )
 272         p_dec->fmt_out.video.i_chroma = VLC_CODEC_TEXT;
 273     else
 274         p_dec->fmt_out.video.i_chroma = VLC_CODEC_RGBA;
 275     return VLC_SUCCESS;
 276 }
 277
 278 /*****************************************************************************
 279  * Close:
 280  *****************************************************************************/
 281 static void Close( vlc_object_t *p_this )
 282 {
 283     decoder_t     *p_dec = (decoder_t*) p_this;
 284     decoder_sys_t *p_sys = p_dec->p_sys;
 285
 286     var_DelCallback( p_dec, "vbi-position", Position, p_sys );
 287     var_DelCallback( p_dec, "vbi-opaque", Opaque, p_sys );
 288     var_DelCallback( p_dec, "vbi-page", RequestPage, p_sys );
 289     var_DelCallback( p_dec->p_libvlc, "key-pressed", EventKey, p_dec );
 290
 291     vlc_mutex_destroy( &p_sys->lock );
 292
 293     if( p_sys->p_vbi_dec )
 294         vbi_decoder_delete( p_sys->p_vbi_dec );
 295     if( p_sys->p_dvb_demux )
 296         vbi_dvb_demux_delete( p_sys->p_dvb_demux );
 297     free( p_sys );
 298 }
 299
 300 #define MAX_SLICES 32
 301
 302 #ifdef WORDS_BIGENDIAN
 303 # define ZVBI_PIXFMT_RGBA32 VBI_PIXFMT_RGBA32_BE
 304 #else
 305 # define ZVBI_PIXFMT_RGBA32 VBI_PIXFMT_RGBA32_LE
 306 #endif
 307
 308
 309 /*****************************************************************************
 310  * Decode:
 311  *****************************************************************************/
 312 static subpicture_t *Decode( decoder_t *p_dec, block_t **pp_block )
 313 {
 314     decoder_sys_t   *p_sys = p_dec->p_sys;
 315     block_t         *p_block;
 316     subpicture_t    *p_spu = NULL;
 317     video_format_t  fmt;
 318     bool            b_cached = false;
 319     vbi_page        p_page;
 320     const uint8_t   *p_pos;
 321     unsigned int    i_left;
 322
 323     if( (pp_block == NULL) || (*pp_block == NULL) )
 324         return NULL;
 325
 326     p_block = *pp_block;
 327     *pp_block = NULL;
 328
 329     p_pos = p_block->p_buffer;
 330     i_left = p_block->i_buffer;
 331
 332     while( i_left > 0 )
 333     {
 334         vbi_sliced      p_sliced[MAX_SLICES];
 335         unsigned int    i_lines = 0;
 336         int64_t         i_pts;
 337
 338         i_lines = vbi_dvb_demux_cor( p_sys->p_dvb_demux, p_sliced,
 339                                      MAX_SLICES, &i_pts, &p_pos, &i_left );
 340
 341         if( i_lines > 0 )
 342             vbi_decode( p_sys->p_vbi_dec, p_sliced, i_lines, i_pts / 90000.0 );
 343     }
 344
 345     /* */
 346     vlc_mutex_lock( &p_sys->lock );
 347     const int i_align = p_sys->i_align;
 348     const unsigned int i_wanted_page = p_sys->i_wanted_page;
 349     const unsigned int i_wanted_subpage = p_sys->i_wanted_subpage;
 350     const bool b_opaque = p_sys->b_opaque;
 351     vlc_mutex_unlock( &p_sys->lock );
 352
 353     /* Try to see if the page we want is in the cache yet */
 354     memset( &p_page, 0, sizeof(vbi_page) );
 355     b_cached = vbi_fetch_vt_page( p_sys->p_vbi_dec, &p_page,
 356                                   vbi_dec2bcd( i_wanted_page ),
 357                                   i_wanted_subpage, VBI_WST_LEVEL_3p5,
 358                                   25, true );
 359
 360     if( i_wanted_page == p_sys->i_last_page && !p_sys->b_update )
 361         goto error;
 362
 363     if( !b_cached )
 364     {
 365         if( p_sys->i_last_page != i_wanted_page )
 366         {
 367             /* We need to reset the subtitle */
 368             p_spu = Subpicture( p_dec, &fmt, true,
 369                                 p_page.columns, p_page.rows,
 370                                 i_align, p_block->i_pts );
 371             if( !p_spu )
 372                 goto error;
 373             p_spu->p_region->psz_text = strdup("");
 374
 375             p_sys->b_update = true;
 376             p_sys->i_last_page = i_wanted_page;
 377             goto exit;
 378         }
 379         goto error;
 380     }
 381
 382     p_sys->b_update = false;
 383     p_sys->i_last_page = i_wanted_page;
 384 #ifdef ZVBI_DEBUG
 385     msg_Dbg( p_dec, "we now have page: %d ready for display",
 386              i_wanted_page );
 387 #endif
 388     /* If there is a page or sub to render, then we do that here */
 389     /* Create the subpicture unit */
 390     p_spu = Subpicture( p_dec, &fmt, p_sys->b_text,
 391                         p_page.columns, p_page.rows,
 392                         i_align, p_block->i_pts );
 393     if( !p_spu )
 394         goto error;
 395
 396     if( p_sys->b_text )
 397     {
 398         unsigned int i_textsize = 7000;
 399         int i_total;
 400         char p_text[i_textsize+1];
 401
 402         i_total = vbi_print_page_region( &p_page, p_text, i_textsize,
 403                         "UTF-8", 0, 0, 0, 0, p_page.columns, p_page.rows );
 404         p_text[i_total] = '\0';
 405         /* Strip off the pagenumber */
 406         if( i_total <= 40 )
 407             goto error;
 408         p_spu->p_region->psz_text = strdup( &p_text[8] );
 409
 410 #ifdef ZVBI_DEBUG
 411         msg_Info( p_dec, "page %x-%x(%d)\n%s", p_page.pgno, p_page.subno, i_total, p_text );
 412 #endif
 413     }
 414     else
 415     {
 416         picture_t *p_pic = p_spu->p_region->p_picture;
 417
 418         /* ZVBI is stupid enough to assume pitch == width */
 419         p_pic->p->i_pitch = 4 * fmt.i_width;
 420         vbi_draw_vt_page( &p_page, ZVBI_PIXFMT_RGBA32,
 421                           p_spu->p_region->p_picture->p->p_pixels, 1, 1 );
 422
 423         vlc_mutex_lock( &p_sys->lock );
 424         memcpy( p_sys->nav_link, &p_page.nav_link, sizeof( p_sys->nav_link )) ;
 425         vlc_mutex_unlock( &p_sys->lock );
 426
 427         OpaquePage( p_pic, p_page, fmt, b_opaque );
 428     }
 429
 430 exit:
 431     vbi_unref_page( &p_page );
 432     block_Release( p_block );
 433     return p_spu;
 434
 435 error:
 436     vbi_unref_page( &p_page );
 437     if( p_spu != NULL )
 438     {
 439         decoder_DeleteSubpicture( p_dec, p_spu );
 440         p_spu = NULL;
 441     }
 442
 443     block_Release( p_block );
 444     return NULL;
 445 }
 446
 447 static subpicture_t *Subpicture( decoder_t *p_dec, video_format_t *p_fmt,
 448                                  bool b_text,
 449                                  int i_columns, int i_rows, int i_align,
 450                                  mtime_t i_pts )
 451 {
 452     video_format_t fmt;
 453     subpicture_t *p_spu;
 454
 455     /* If there is a page or sub to render, then we do that here */
 456     /* Create the subpicture unit */
 457     p_spu = decoder_NewSubpicture( p_dec, NULL );
 458     if( !p_spu )
 459     {
 460         msg_Warn( p_dec, "can't get spu buffer" );
 461         return NULL;
 462     }
 463
 464     memset( &fmt, 0, sizeof(video_format_t) );
 465     fmt.i_chroma = b_text ? VLC_CODEC_TEXT :
 466                                    VLC_CODEC_RGBA;
 467     if( b_text )
 468     {
 469         fmt.i_bits_per_pixel = 0;
 470         fmt.i_sar_num = 0;
 471         fmt.i_sar_den = 0;
 472     }
 473     else
 474     {
 475         fmt.i_sar_num = 1;
 476         fmt.i_sar_den = 1;
 477         fmt.i_width = fmt.i_visible_width = i_columns * 12;
 478         fmt.i_height = fmt.i_visible_height = i_rows * 10;
 479         fmt.i_bits_per_pixel = 32;
 480     }
 481     fmt.i_x_offset = fmt.i_y_offset = 0;
 482
 483     p_spu->p_region = subpicture_region_New( &fmt );
 484     if( p_spu->p_region == NULL )
 485     {
 486         msg_Err( p_dec, "cannot allocate SPU region" );
 487         decoder_DeleteSubpicture( p_dec, p_spu );
 488         return NULL;
 489     }
 490
 491     p_spu->p_region->i_x = 0;
 492     p_spu->p_region->i_y = 0;
 493     p_spu->p_region->i_align = i_align;
 494
 495     p_spu->i_start = i_pts;
 496     p_spu->i_stop = 0;
 497     p_spu->b_ephemer = true;
 498     p_spu->b_absolute = false;
 499
 500     if( !b_text )
 501     {
 502         p_spu->i_original_picture_width = fmt.i_width;
 503         p_spu->i_original_picture_height = fmt.i_height;
 504     }
 505
 506     /* */
 507     *p_fmt = fmt;
 508     return p_spu;
 509 }
 510
 511 static void EventHandler( vbi_event *ev, void *user_data )
 512 {
 513     decoder_t *p_dec        = (decoder_t *)user_data;
 514     decoder_sys_t *p_sys    = p_dec->p_sys;
 515
 516     if( ev->type == VBI_EVENT_TTX_PAGE )
 517     {
 518 #ifdef ZVBI_DEBUG
 519         msg_Info( p_dec, "Page %03x.%02x ",
 520                     ev->ev.ttx_page.pgno,
 521                     ev->ev.ttx_page.subno & 0xFF);
 522 #endif
 523         if( p_sys->i_last_page == vbi_bcd2dec( ev->ev.ttx_page.pgno ) )
 524             p_sys->b_update = true;
 525 #ifdef ZVBI_DEBUG
 526         if( ev->ev.ttx_page.clock_update )
 527             msg_Dbg( p_dec, "clock" );
 528         if( ev->ev.ttx_page.header_update )
 529             msg_Dbg( p_dec, "header" );
 530 #endif
 531     }
 532     else if( ev->type == VBI_EVENT_CLOSE )
 533         msg_Dbg( p_dec, "Close event" );
 534     else if( ev->type == VBI_EVENT_CAPTION )
 535         msg_Dbg( p_dec, "Caption line: %x", ev->ev.caption.pgno );
 536     else if( ev->type == VBI_EVENT_NETWORK )
 537     {
 538         msg_Dbg( p_dec, "Network change");
 539         vbi_network n = ev->ev.network;
 540         msg_Dbg( p_dec, "Network id:%d name: %s, call: %s ", n.nuid, n.name, n.call );
 541     }
 542     else if( ev->type == VBI_EVENT_TRIGGER )
 543         msg_Dbg( p_dec, "Trigger event" );
 544     else if( ev->type == VBI_EVENT_ASPECT )
 545         msg_Dbg( p_dec, "Aspect update" );
 546     else if( ev->type == VBI_EVENT_PROG_INFO )
 547         msg_Dbg( p_dec, "Program info received" );
 548     else if( ev->type == VBI_EVENT_NETWORK_ID )
 549         msg_Dbg( p_dec, "Network ID changed" );
 550 }
 551
 552 static int OpaquePage( picture_t *p_src, const vbi_page p_page,
 553                        const video_format_t fmt, bool b_opaque )
 554 {
 555     unsigned int    x, y;
 556
 557     assert( fmt.i_chroma == VLC_CODEC_RGBA );
 558
 559     /* Kludge since zvbi doesn't provide an option to specify opacity. */
 560     for( y = 0; y < fmt.i_height; y++ )
 561     {
 562         for( x = 0; x < fmt.i_width; x++ )
 563         {
 564             const vbi_opacity opacity = p_page.text[ y/10 * p_page.columns + x/12 ].opacity;
 565             const int background = p_page.text[ y/10 * p_page.columns + x/12 ].background;
 566             uint32_t *p_pixel = (uint32_t*)&p_src->p->p_pixels[y * p_src->p->i_pitch + 4*x];
 567
 568             switch( opacity )
 569             {
 570             /* Show video instead of this character */
 571             case VBI_TRANSPARENT_SPACE:
 572                 *p_pixel = 0;
 573                 break;
 574             /* Display foreground and background color */
 575             /* To make the boxed text "closed captioning" transparent
 576              * change true to false.
 577              */
 578             case VBI_OPAQUE:
 579             /* alpha blend video into background color */
 580             case VBI_SEMI_TRANSPARENT:
 581                 if( b_opaque )
 582                     break;
 583             /* Full text transparency. only foreground color is show */
 584             case VBI_TRANSPARENT_FULL:
 585                 if( (*p_pixel) == (0xff000000 | p_page.color_map[background] ) )
 586                     *p_pixel = 0;
 587                 break;
 588             }
 589         }
 590     }
 591     /* end of kludge */
 592     return VLC_SUCCESS;
 593 }
 594
 595 /* Callbacks */
 596 static int RequestPage( vlc_object_t *p_this, char const *psz_cmd,
 597                         vlc_value_t oldval, vlc_value_t newval, void *p_data )
 598 {
 599     decoder_sys_t *p_sys = p_data;
 600     VLC_UNUSED(p_this); VLC_UNUSED(psz_cmd); VLC_UNUSED(oldval);
 601
 602     vlc_mutex_lock( &p_sys->lock );
 603     switch( newval.i_int )
 604     {
 605         case ZVBI_KEY_RED:
 606             p_sys->i_wanted_page = vbi_bcd2dec( p_sys->nav_link[0].pgno );
 607             p_sys->i_wanted_subpage = p_sys->nav_link[0].subno;
 608             break;
 609         case ZVBI_KEY_GREEN:
 610             p_sys->i_wanted_page = vbi_bcd2dec( p_sys->nav_link[1].pgno );
 611             p_sys->i_wanted_subpage = p_sys->nav_link[1].subno;
 612             break;
 613         case ZVBI_KEY_YELLOW:
 614             p_sys->i_wanted_page = vbi_bcd2dec( p_sys->nav_link[2].pgno );
 615             p_sys->i_wanted_subpage = p_sys->nav_link[2].subno;
 616             break;
 617         case ZVBI_KEY_BLUE:
 618             p_sys->i_wanted_page = vbi_bcd2dec( p_sys->nav_link[3].pgno );
 619             p_sys->i_wanted_subpage = p_sys->nav_link[3].subno;
 620             break;
 621         case ZVBI_KEY_INDEX:
 622             p_sys->i_wanted_page = vbi_bcd2dec( p_sys->nav_link[5].pgno ); /* #4 is SKIPPED */
 623             p_sys->i_wanted_subpage = p_sys->nav_link[5].subno;
 624             break;
 625     }
 626     if( newval.i_int > 0 && newval.i_int < 999 )
 627     {
 628         p_sys->i_wanted_page = newval.i_int;
 629         p_sys->i_wanted_subpage = VBI_ANY_SUBNO;
 630     }
 631     vlc_mutex_unlock( &p_sys->lock );
 632
 633     return VLC_SUCCESS;
 634 }
 635
 636 static int Opaque( vlc_object_t *p_this, char const *psz_cmd,
 637                    vlc_value_t oldval, vlc_value_t newval, void *p_data )
 638 {
 639     decoder_sys_t *p_sys = p_data;
 640     VLC_UNUSED(p_this); VLC_UNUSED(psz_cmd); VLC_UNUSED(oldval);
 641
 642     vlc_mutex_lock( &p_sys->lock );
 643     p_sys->b_opaque = newval.b_bool;
 644     p_sys->b_update = true;
 645     vlc_mutex_unlock( &p_sys->lock );
 646
 647     return VLC_SUCCESS;
 648 }
 649
 650 static int Position( vlc_object_t *p_this, char const *psz_cmd,
 651                      vlc_value_t oldval, vlc_value_t newval, void *p_data )
 652 {
 653     decoder_sys_t *p_sys = p_data;
 654     VLC_UNUSED(p_this); VLC_UNUSED(psz_cmd); VLC_UNUSED(oldval);
 655
 656     vlc_mutex_lock( &p_sys->lock );
 657     p_sys->i_align = newval.i_int;
 658     vlc_mutex_unlock( &p_sys->lock );
 659
 660     return VLC_SUCCESS;
 661 }
 662
 663 static int EventKey( vlc_object_t *p_this, char const *psz_cmd,
 664                         vlc_value_t oldval, vlc_value_t newval, void *p_data )
 665 {
 666     decoder_t *p_dec = p_data;
 667     decoder_sys_t *p_sys = p_dec->p_sys;
 668
 669     VLC_UNUSED(psz_cmd); VLC_UNUSED(oldval); VLC_UNUSED( p_this );
 670
 671     /* FIXME: Capture + and - key for subpage browsing */
 672     if( newval.i_int == '-' || newval.i_int == '+' )
 673     {
 674         vlc_mutex_lock( &p_sys->lock );
 675         if( p_sys->i_wanted_subpage == VBI_ANY_SUBNO && newval.i_int == '+' )
 676             p_sys->i_wanted_subpage = vbi_dec2bcd(1);
 677         else if ( newval.i_int == '+' )
 678             p_sys->i_wanted_subpage = vbi_add_bcd( p_sys->i_wanted_subpage, 1);
 679         else if( newval.i_int == '-')
 680             p_sys->i_wanted_subpage = vbi_add_bcd( p_sys->i_wanted_subpage, 0xF9999999); /* BCD complement - 1 */
 681
 682         if ( !vbi_bcd_digits_greater( p_sys->i_wanted_subpage, 0x00 ) || vbi_bcd_digits_greater( p_sys->i_wanted_subpage, 0x99 ) )
 683                 p_sys->i_wanted_subpage = VBI_ANY_SUBNO;
 684         else
 685             msg_Info( p_dec, "subpage: %d",
 686                       vbi_bcd2dec( p_sys->i_wanted_subpage) );
 687
 688         p_sys->b_update = true;
 689         vlc_mutex_unlock( &p_sys->lock );
 690     }
 691
 692     /* Capture 0-9 for page selection */
 693     if( newval.i_int < '0' || newval.i_int > '9' )
 694         return VLC_SUCCESS;
 695
 696     vlc_mutex_lock( &p_sys->lock );
 697     p_sys->i_key[0] = p_sys->i_key[1];
 698     p_sys->i_key[1] = p_sys->i_key[2];
 699     p_sys->i_key[2] = (int)(newval.i_int - '0');
 700     msg_Info( p_dec, "page: %c%c%c", (char)(p_sys->i_key[0]+'0'),
 701               (char)(p_sys->i_key[1]+'0'), (char)(p_sys->i_key[2]+'0') );
 702
 703     int i_new_page = 0;
 704
 705     if( p_sys->i_key[0] > 0 && p_sys->i_key[0] <= 8 &&
 706         p_sys->i_key[1] >= 0 && p_sys->i_key[1] <= 9 &&
 707         p_sys->i_key[2] >= 0 && p_sys->i_key[2] <= 9 )
 708     {
 709         i_new_page = p_sys->i_key[0]*100 + p_sys->i_key[1]*10 + p_sys->i_key[2];
 710         p_sys->i_key[0] = p_sys->i_key[1] = p_sys->i_key[2] = '*' - '0';
 711     }
 712     vlc_mutex_unlock( &p_sys->lock );
 713
 714     if( i_new_page > 0 )
 715         var_SetInteger( p_dec, "vbi-page", i_new_page );
 716
 717     return VLC_SUCCESS;
 718 }