modules/codec/telx.c

   1 /*****************************************************************************
   2  * telx.c : Minimalistic Teletext subtitles decoder
   3  *****************************************************************************
   4  * Copyright (C) 2007 Vincent Penne
   5  * Some code converted from ProjectX java dvb decoder (c) 2001-2005 by dvb.matt
   6  * $Id$
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22 /*****************************************************************************
  23  *
  24  * information on teletext format can be found here :
  25  * http://pdc.ro.nu/teletext.html
  26  *
  27  *****************************************************************************/
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31 #include <assert.h>
  32 #include <stdint.h>
  33
  34 #include <vlc_common.h>
  35 #include <vlc_plugin.h>
  36
  37 #include <vlc_bits.h>
  38 #include <vlc_codec.h>
  39
  40 /* #define TELX_DEBUG */
  41 #ifdef TELX_DEBUG
  42 #   define dbg( a ) msg_Dbg a
  43 #else
  44 #   define dbg( a )
  45 #endif
  46
  47 /*****************************************************************************
  48  * Module descriptor.
  49  *****************************************************************************/
  50 static int  Open ( vlc_object_t * );
  51 static void Close( vlc_object_t * );
  52 static int  Decode( decoder_t *, block_t * );
  53
  54 #define OVERRIDE_PAGE_TEXT N_("Override page")
  55 #define OVERRIDE_PAGE_LONGTEXT N_("Override the indicated page, try this if " \
  56         "your subtitles don't appear (-1 = autodetect from TS, " \
  57         "0 = autodetect from teletext, " \
  58         ">0 = actual page number, usually 888 or 889).")
  59
  60 #define IGNORE_SUB_FLAG_TEXT N_("Ignore subtitle flag")
  61 #define IGNORE_SUB_FLAG_LONGTEXT N_("Ignore the subtitle flag, try this if " \
  62         "your subtitles don't appear.")
  63
  64 #define FRENCH_WORKAROUND_TEXT N_("Workaround for France")
  65 #define FRENCH_WORKAROUND_LONGTEXT N_("Some French channels do not flag " \
  66         "their subtitling pages correctly due to a historical " \
  67         "interpretation mistake. Try using this wrong interpretation if " \
  68         "your subtitles don't appear.")
  69
  70 vlc_module_begin ()
  71     set_description( N_("Teletext subtitles decoder") )
  72     set_shortname( "Teletext" )
  73     set_capability( "spu decoder", 50 )
  74     set_category( CAT_INPUT )
  75     set_subcategory( SUBCAT_INPUT_SCODEC )
  76     set_callbacks( Open, Close )
  77
  78     add_integer( "telx-override-page", -1,
  79                  OVERRIDE_PAGE_TEXT, OVERRIDE_PAGE_LONGTEXT, true )
  80     add_bool( "telx-ignore-subtitle-flag", false,
  81               IGNORE_SUB_FLAG_TEXT, IGNORE_SUB_FLAG_LONGTEXT, true )
  82     add_bool( "telx-french-workaround", false,
  83               FRENCH_WORKAROUND_TEXT, FRENCH_WORKAROUND_LONGTEXT, true )
  84
  85 vlc_module_end ()
  86
  87 /****************************************************************************
  88  * Local structures
  89  ****************************************************************************/
  90
  91 typedef struct
  92 {
  93   int         i_align;
  94   bool        b_is_subtitle[9];
  95   char        ppsz_lines[32][128];
  96   char        psz_prev_text[512];
  97   vlc_tick_t  prev_pts;
  98   int         i_page[9];
  99   bool        b_erase[9];
 100   const uint16_t *  pi_active_national_set[9];
 101   int         i_wanted_page, i_wanted_magazine;
 102   bool        b_ignore_sub_flag;
 103 } decoder_sys_t;
 104
 105 /****************************************************************************
 106  * Local data
 107  ****************************************************************************/
 108
 109 /*
 110  * My doc only mentions 13 national characters, but experiments show there
 111  * are more, in france for example I already found two more (0x9 and 0xb).
 112  *
 113  * Conversion is in this order :
 114  *
 115  * 0x23 0x24 0x40 0x5b 0x5c 0x5d 0x5e 0x5f 0x60 0x7b 0x7c 0x7d 0x7e
 116  * (these are the standard ones)
 117  * 0x08 0x09 0x0a 0x0b 0x0c 0x0d (apparently a control character) 0x0e 0x0f
 118  */
 119
 120 static const uint16_t ppi_national_subsets[][20] =
 121 {
 122   { 0x00a3, 0x0024, 0x0040, 0x00ab, 0x00bd, 0x00bb, 0x005e, 0x0023,
 123     0x002d, 0x00bc, 0x00a6, 0x00be, 0x00f7 }, /* english ,000 */
 124
 125   { 0x00e9, 0x00ef, 0x00e0, 0x00eb, 0x00ea, 0x00f9, 0x00ee, 0x0023,
 126     0x00e8, 0x00e2, 0x00f4, 0x00fb, 0x00e7, 0, 0x00eb, 0, 0x00ef }, /* french  ,001 */
 127
 128   { 0x0023, 0x00a4, 0x00c9, 0x00c4, 0x00d6, 0x00c5, 0x00dc, 0x005f,
 129     0x00e9, 0x00e4, 0x00f6, 0x00e5, 0x00fc }, /* swedish,finnish,hungarian ,010 */
 130
 131   { 0x0023, 0x016f, 0x010d, 0x0165, 0x017e, 0x00fd, 0x00ed, 0x0159,
 132     0x00e9, 0x00e1, 0x011b, 0x00fa, 0x0161 }, /* czech,slovak  ,011 */
 133
 134   { 0x0023, 0x0024, 0x00a7, 0x00c4, 0x00d6, 0x00dc, 0x005e, 0x005f,
 135     0x00b0, 0x00e4, 0x00f6, 0x00fc, 0x00df }, /* german ,100 */
 136
 137   { 0x00e7, 0x0024, 0x00a1, 0x00e1, 0x00e9, 0x00ed, 0x00f3, 0x00fa,
 138     0x00bf, 0x00fc, 0x00f1, 0x00e8, 0x00e0 }, /* portuguese,spanish ,101 */
 139
 140   { 0x00a3, 0x0024, 0x00e9, 0x00b0, 0x00e7, 0x00bb, 0x005e, 0x0023,
 141     0x00f9, 0x00e0, 0x00f2, 0x00e8, 0x00ec }, /* italian  ,110 */
 142
 143   { 0x0023, 0x00a4, 0x0162, 0x00c2, 0x015e, 0x0102, 0x00ce, 0x0131,
 144     0x0163, 0x00e2, 0x015f, 0x0103, 0x00ee }, /* rumanian ,111 */
 145
 146   /* I have these tables too, but I don't know how they can be triggered */
 147   { 0x0023, 0x0024, 0x0160, 0x0117, 0x0119, 0x017d, 0x010d, 0x016b,
 148     0x0161, 0x0105, 0x0173, 0x017e, 0x012f }, /* lettish,lithuanian ,1000 */
 149
 150   { 0x0023, 0x0144, 0x0105, 0x005a, 0x015a, 0x0141, 0x0107, 0x00f3,
 151     0x0119, 0x017c, 0x015b, 0x0142, 0x017a }, /* polish,  1001 */
 152
 153   { 0x0023, 0x00cb, 0x010c, 0x0106, 0x017d, 0x0110, 0x0160, 0x00eb,
 154     0x010d, 0x0107, 0x017e, 0x0111, 0x0161 }, /* serbian,croatian,slovenian, 1010 */
 155
 156   { 0x0023, 0x00f5, 0x0160, 0x00c4, 0x00d6, 0x017e, 0x00dc, 0x00d5,
 157     0x0161, 0x00e4, 0x00f6, 0x017e, 0x00fc }, /* estonian  ,1011 */
 158
 159   { 0x0054, 0x011f, 0x0130, 0x015e, 0x00d6, 0x00c7, 0x00dc, 0x011e,
 160     0x0131, 0x015f, 0x00f6, 0x00e7, 0x00fc }, /* turkish  ,1100 */
 161 };
 162
 163
 164 /*****************************************************************************
 165  * Open: probe the decoder and return score
 166  *****************************************************************************
 167  * Tries to launch a decoder and return score so that the interface is able
 168  * to chose.
 169  *****************************************************************************/
 170 static int Open( vlc_object_t *p_this )
 171 {
 172     decoder_t     *p_dec = (decoder_t *) p_this;
 173     decoder_sys_t *p_sys = NULL;
 174     int            i_val;
 175
 176
 177     if( p_dec->fmt_in.i_codec != VLC_CODEC_TELETEXT)
 178     {
 179         return VLC_EGENERIC;
 180     }
 181
 182     p_dec->pf_decode = Decode;
 183     p_sys = p_dec->p_sys = calloc( 1, sizeof(*p_sys) );
 184     if( p_sys == NULL )
 185         return VLC_ENOMEM;
 186     p_dec->fmt_out.i_codec = 0;
 187
 188     p_sys->i_align = 0;
 189     for ( int i = 0; i < 9; i++ )
 190         p_sys->pi_active_national_set[i] = ppi_national_subsets[1];
 191
 192     i_val = var_CreateGetInteger( p_dec, "telx-override-page" );
 193     if( i_val == -1 && p_dec->fmt_in.subs.teletext.i_magazine != -1 &&
 194         ( p_dec->fmt_in.subs.teletext.i_magazine != 1 ||
 195           p_dec->fmt_in.subs.teletext.i_page != 0 ) ) /* ignore if TS demux wants page 100 (unlikely to be sub) */
 196     {
 197         bool b_val;
 198         p_sys->i_wanted_magazine = p_dec->fmt_in.subs.teletext.i_magazine;
 199         p_sys->i_wanted_page = p_dec->fmt_in.subs.teletext.i_page;
 200
 201         b_val = var_CreateGetBool( p_dec, "telx-french-workaround" );
 202         if( p_sys->i_wanted_page < 100 &&
 203             (b_val || (p_sys->i_wanted_page % 16) >= 10))
 204         {
 205             /* See http://www.nada.kth.se/~ragge/vdr/ttxtsubs/TROUBLESHOOTING.txt
 206              * paragraph about French channels - they mix up decimal and
 207              * hexadecimal */
 208             p_sys->i_wanted_page = (p_sys->i_wanted_page / 10) * 16 +
 209                                    (p_sys->i_wanted_page % 10);
 210         }
 211     }
 212     else if( i_val <= 0 )
 213     {
 214         p_sys->i_wanted_magazine = -1;
 215         p_sys->i_wanted_page = -1;
 216     }
 217     else
 218     {
 219         p_sys->i_wanted_magazine = i_val / 100;
 220         p_sys->i_wanted_page = (((i_val % 100) / 10) << 4)
 221                                |((i_val % 100) % 10);
 222     }
 223     p_sys->b_ignore_sub_flag = var_CreateGetBool( p_dec,
 224                                     "telx-ignore-subtitle-flag" );
 225
 226     msg_Dbg( p_dec, "starting telx on magazine %d page %02x flag %d",
 227              p_sys->i_wanted_magazine, p_sys->i_wanted_page,
 228              p_sys->b_ignore_sub_flag );
 229
 230     return VLC_SUCCESS;
 231
 232 /*  error: */
 233 /*     if (p_sys) { */
 234 /*       free(p_sys); */
 235 /*       p_sys = NULL; */
 236 /*     } */
 237 /*     return VLC_EGENERIC; */
 238 }
 239
 240 /*****************************************************************************
 241  * Close:
 242  *****************************************************************************/
 243 static void Close( vlc_object_t *p_this )
 244 {
 245     decoder_t     *p_dec = (decoder_t*) p_this;
 246     decoder_sys_t *p_sys = p_dec->p_sys;
 247
 248     free( p_sys );
 249 }
 250
 251 /**************************
 252  * change bits endianness *
 253  **************************/
 254 static uint8_t bytereverse( int n )
 255 {
 256     n = (((n >> 1) & 0x55) | ((n << 1) & 0xaa));
 257     n = (((n >> 2) & 0x33) | ((n << 2) & 0xcc));
 258     n = (((n >> 4) & 0x0f) | ((n << 4) & 0xf0));
 259     return n;
 260 }
 261
 262 static int hamming_8_4( int a )
 263 {
 264     switch (a) {
 265     case 0xA8:
 266         return 0;
 267     case 0x0B:
 268         return 1;
 269     case 0x26:
 270         return 2;
 271     case 0x85:
 272         return 3;
 273     case 0x92:
 274         return 4;
 275     case 0x31:
 276         return 5;
 277     case 0x1C:
 278         return 6;
 279     case 0xBF:
 280         return 7;
 281     case 0x40:
 282         return 8;
 283     case 0xE3:
 284         return 9;
 285     case 0xCE:
 286         return 10;
 287     case 0x6D:
 288         return 11;
 289     case 0x7A:
 290         return 12;
 291     case 0xD9:
 292         return 13;
 293     case 0xF4:
 294         return 14;
 295     case 0x57:
 296         return 15;
 297     default:
 298         return -1;     // decoding error , not yet corrected
 299     }
 300 }
 301
 302 // utc-2 --> utf-8
 303 // this is not a general function, but it's enough for what we do here
 304 // the result buffer need to be at least 4 bytes long
 305 static void to_utf8( char * res, uint16_t ch )
 306 {
 307     if( ch >= 0x80 )
 308     {
 309         if( ch >= 0x800 )
 310         {
 311             res[0] = (ch >> 12) | 0xE0;
 312             res[1] = ((ch >> 6) & 0x3F) | 0x80;
 313             res[2] = (ch & 0x3F) | 0x80;
 314             res[3] = 0;
 315         }
 316         else
 317         {
 318             res[0] = (ch >> 6) | 0xC0;
 319             res[1] = (ch & 0x3F) | 0x80;
 320             res[2] = 0;
 321         }
 322     }
 323     else
 324     {
 325         res[0] = ch;
 326         res[1] = 0;
 327     }
 328 }
 329
 330 static void decode_string( char * res, int res_len,
 331                            decoder_sys_t *p_sys, int magazine,
 332                            uint8_t * packet, int len )
 333 {
 334     char utf8[7];
 335     char * pt = res;
 336
 337     for ( int i = 0; i < len; i++ )
 338     {
 339         int in = bytereverse( packet[i] ) & 0x7f;
 340         uint16_t out = 32;
 341         size_t l;
 342
 343         switch ( in )
 344         {
 345         /* special national characters */
 346         case 0x23:
 347             out = p_sys->pi_active_national_set[magazine][0];
 348             break;
 349         case 0x24:
 350             out = p_sys->pi_active_national_set[magazine][1];
 351             break;
 352         case 0x40:
 353             out = p_sys->pi_active_national_set[magazine][2];
 354             break;
 355         case 0x5b:
 356             out = p_sys->pi_active_national_set[magazine][3];
 357             break;
 358         case 0x5c:
 359             out = p_sys->pi_active_national_set[magazine][4];
 360             break;
 361         case 0x5d:
 362             out = p_sys->pi_active_national_set[magazine][5];
 363             break;
 364         case 0x5e:
 365             out = p_sys->pi_active_national_set[magazine][6];
 366             break;
 367         case 0x5f:
 368             out = p_sys->pi_active_national_set[magazine][7];
 369             break;
 370         case 0x60:
 371             out = p_sys->pi_active_national_set[magazine][8];
 372             break;
 373         case 0x7b:
 374             out = p_sys->pi_active_national_set[magazine][9];
 375             break;
 376         case 0x7c:
 377             out = p_sys->pi_active_national_set[magazine][10];
 378             break;
 379         case 0x7d:
 380             out = p_sys->pi_active_national_set[magazine][11];
 381             break;
 382         case 0x7e:
 383             out = p_sys->pi_active_national_set[magazine][12];
 384             break;
 385
 386         /* some special control characters (empirical) */
 387         case 0x0d:
 388             /* apparently this starts a sequence that ends with 0xb 0xb */
 389             while ( i + 1 < len && (bytereverse( packet[i+1] ) & 0x7f) != 0x0b )
 390                 i++;
 391             i += 2;
 392             break;
 393             /* goto skip; */
 394
 395         default:
 396             /* non documented national range 0x08 - 0x0f */
 397             if ( in >= 0x08 && in <= 0x0f )
 398             {
 399                 out = p_sys->pi_active_national_set[magazine][13 + in - 8];
 400                 break;
 401             }
 402
 403             /* normal ascii */
 404             if ( in > 32 && in < 0x7f )
 405                 out = in;
 406         }
 407
 408         /* handle undefined national characters */
 409         if ( out == 0 )
 410             out = 32;
 411
 412         /* convert to utf-8 */
 413         to_utf8( utf8, out );
 414         l = strlen( utf8 );
 415         if ( pt + l < res + res_len - 1 )
 416         {
 417             strcpy(pt, utf8);
 418             pt += l;
 419         }
 420
 421         /* skip: ; */
 422     }
 423     /* end: */
 424     *pt++ = 0;
 425 }
 426
 427 /*****************************************************************************
 428  * Decode:
 429  *****************************************************************************/
 430 static int Decode( decoder_t *p_dec, block_t *p_block )
 431 {
 432     decoder_sys_t *p_sys = p_dec->p_sys;
 433     subpicture_t  *p_spu = NULL;
 434     video_format_t fmt;
 435     /* int erase = 0; */
 436     int len;
 437 #if 0
 438     int i_wanted_magazine = i_conf_wanted_page / 100;
 439     int i_wanted_page = 0x10 * ((i_conf_wanted_page % 100) / 10)
 440                          | (i_conf_wanted_page % 10);
 441 #endif
 442     bool b_update = false;
 443     char psz_text[512], *pt = psz_text;
 444     char psz_line[256];
 445     int total;
 446
 447     if( p_block == NULL ) /* No Drain */
 448         return VLCDEC_SUCCESS;
 449
 450     dbg((p_dec, "start of telx packet with header %2x\n",
 451                 * (uint8_t *) p_block->p_buffer));
 452     len = p_block->i_buffer;
 453     for ( int offset = 1; offset + 46 <= len; offset += 46 )
 454     {
 455         uint8_t * packet = (uint8_t *) p_block->p_buffer+offset;
 456 //        int vbi = ((0x20 & packet[2]) != 0 ? 0 : 313) + (0x1F & packet[2]);
 457
 458 //        dbg((p_dec, "vbi %d header %02x %02x %02x\n", vbi, packet[0], packet[1], packet[2]));
 459         if ( packet[0] == 0xFF ) continue;
 460
 461 /*      if (packet[1] != 0x2C) { */
 462 /*         printf("wrong header\n"); */
 463 /*         //goto error; */
 464 /*         continue; */
 465 /*       } */
 466
 467         int mpag = (hamming_8_4( packet[4] ) << 4) | hamming_8_4( packet[5] );
 468         int row, magazine;
 469         if ( mpag < 0 )
 470         {
 471             /* decode error */
 472             dbg((p_dec, "mpag hamming error\n"));
 473             continue;
 474         }
 475
 476         row = 0xFF & bytereverse(mpag);
 477         magazine = (7 & row) == 0 ? 8 : (7 & row);
 478         row >>= 3;
 479
 480         if ( p_sys->i_wanted_page != -1
 481               && magazine != p_sys->i_wanted_magazine )
 482             continue;
 483
 484         if ( row == 0 )
 485         {
 486             /* row 0 : flags and header line */
 487             int flag = 0;
 488
 489             for ( int a = 0; a < 6; a++ )
 490             {
 491                 flag |= (0xF & (bytereverse( hamming_8_4(packet[8 + a]) ) >> 4))
 492                           << (a * 4);
 493             }
 494
 495     /*         if (!p_sys->b_ignore_sub_flag && !(1 & flag>>15)) */
 496     /*           continue; */
 497
 498             p_sys->i_page[magazine] = (0xF0 & bytereverse( hamming_8_4(packet[7]) )) |
 499                              (0xF & (bytereverse( hamming_8_4(packet[6]) ) >> 4) );
 500
 501             decode_string( psz_line, sizeof(psz_line), p_sys, magazine,
 502                            packet + 14, 40 - 14 );
 503
 504             dbg((p_dec, "mag %d flags %x page %x character set %d subtitles %d", magazine, flag,
 505                  p_sys->i_page[magazine],
 506                  7 & flag>>21, 1 & flag>>15, psz_line));
 507
 508             p_sys->pi_active_national_set[magazine] =
 509                                  ppi_national_subsets[7 & (flag >> 21)];
 510
 511             p_sys->b_is_subtitle[magazine] = p_sys->b_ignore_sub_flag
 512                                               || ( (1 & (flag >> 15))
 513                                                   && (1 & (flag>>16)) );
 514
 515             dbg(( p_dec, "FLAGS%s%s%s%s%s%s%s mag_ser %d",
 516                   (1 & (flag>>14))? " news" : "",
 517                   (1 & (flag>>15))? " subtitle" : "",
 518                   (1 & (flag>>7))? " erase" : "",
 519                   (1 & (flag>>16))? " suppressed_head" : "",
 520                   (1 & (flag>>17))? " update" : "",
 521                   (1 & (flag>>18))? " interrupt" : "",
 522                   (1 & (flag>>19))? " inhibit" : "",
 523                   (1 & (flag>>20)) ));
 524
 525             if ( (p_sys->i_wanted_page != -1
 526                    && p_sys->i_page[magazine] != p_sys->i_wanted_page)
 527                    || !p_sys->b_is_subtitle[magazine] )
 528                 continue;
 529
 530             p_sys->b_erase[magazine] = (1 & (flag >> 7));
 531
 532             dbg((p_dec, "%ld --> %ld\n", (long int) p_block->i_pts, (long int)(p_sys->prev_pts+1500000)));
 533             /* kludge here :
 534              * we ignore the erase flag if it happens less than 1.5 seconds
 535              * before last caption
 536              * TODO   make this time configurable
 537              * UPDATE the kludge seems to be no more necessary
 538              *        so it's commented out*/
 539             if ( /*p_block->i_pts > p_sys->prev_pts + 1500000 && */
 540                  p_sys->b_erase[magazine] )
 541             {
 542                 dbg((p_dec, "ERASE !\n"));
 543
 544                 p_sys->b_erase[magazine] = 0;
 545                 for ( int i = 1; i < 32; i++ )
 546                 {
 547                     if ( !p_sys->ppsz_lines[i][0] ) continue;
 548                     /* b_update = true; */
 549                     p_sys->ppsz_lines[i][0] = 0;
 550                 }
 551             }
 552
 553             /* replace the row if it's different */
 554             if ( strcmp(psz_line, p_sys->ppsz_lines[row]) )
 555             {
 556                 strncpy( p_sys->ppsz_lines[row], psz_line,
 557                          sizeof(p_sys->ppsz_lines[row]) - 1);
 558             }
 559             b_update = true;
 560
 561         }
 562         else if ( row < 24 )
 563         {
 564             char * t;
 565             int i;
 566             /* row 1-23 : normal lines */
 567
 568             if ( (p_sys->i_wanted_page != -1
 569                    && p_sys->i_page[magazine] != p_sys->i_wanted_page)
 570                    || !p_sys->b_is_subtitle[magazine]
 571                    || (p_sys->i_wanted_page == -1
 572                         && p_sys->i_page[magazine] > 0x99) )
 573                 continue;
 574
 575             decode_string( psz_line, sizeof(psz_line), p_sys, magazine,
 576                            packet + 6, 40 );
 577             t = psz_line;
 578
 579             /* remove starting spaces */
 580             while ( *t == 32 ) t++;
 581
 582             /* remove trailing spaces */
 583             for ( i = strlen(t) - 1; i >= 0 && t[i] == 32; i-- );
 584             t[i + 1] = 0;
 585
 586             /* replace the row if it's different */
 587             if ( strcmp( t, p_sys->ppsz_lines[row] ) )
 588             {
 589                 strncpy( p_sys->ppsz_lines[row], t,
 590                          sizeof(p_sys->ppsz_lines[row]) - 1 );
 591                 b_update = true;
 592             }
 593
 594             if (t[0])
 595                 p_sys->prev_pts = p_block->i_pts;
 596
 597             dbg((p_dec, "%d %d : ", magazine, row));
 598             dbg((p_dec, "%s\n", t));
 599
 600 #ifdef TELX_DEBUG
 601             {
 602                 char dbg[256];
 603                 dbg[0] = 0;
 604                 for ( i = 0; i < 40; i++ )
 605                 {
 606                     int in = bytereverse(packet[6 + i]) & 0x7f;
 607                     sprintf(dbg + strlen(dbg), "%02x ", in);
 608                 }
 609                 dbg((p_dec, "%s\n", dbg));
 610                 dbg[0] = 0;
 611                 for ( i = 0; i < 40; i++ )
 612                 {
 613                     decode_string( psz_line, sizeof(psz_line), p_sys, magazine,
 614                                    packet + 6 + i, 1 );
 615                     sprintf( dbg + strlen(dbg), "%s  ", psz_line );
 616                 }
 617                 dbg((p_dec, "%s\n", dbg));
 618             }
 619 #endif
 620         }
 621         else if ( row == 25 )
 622         {
 623             /* row 25 : alternate header line */
 624             if ( (p_sys->i_wanted_page != -1
 625                    && p_sys->i_page[magazine] != p_sys->i_wanted_page)
 626                    || !p_sys->b_is_subtitle[magazine] )
 627                 continue;
 628
 629             decode_string( psz_line, sizeof(psz_line), p_sys, magazine,
 630                            packet + 6, 40 );
 631
 632             /* replace the row if it's different */
 633             if ( strcmp( psz_line, p_sys->ppsz_lines[0] ) )
 634             {
 635                 strncpy( p_sys->ppsz_lines[0], psz_line,
 636                          sizeof(p_sys->ppsz_lines[0]) - 1 );
 637                 /* b_update = true; */
 638             }
 639         }
 640 /*       else if (row == 26) { */
 641 /*         // row 26 : TV listings */
 642 /*       } else */
 643 /*         dbg((p_dec, "%d %d : %s\n", magazine, row, decode_string(p_sys, magazine, packet+6, 40))); */
 644     }
 645
 646     if ( !b_update )
 647         goto error;
 648
 649     total = 0;
 650     for ( int i = 1; i < 24; i++ )
 651     {
 652         size_t l = strlen( p_sys->ppsz_lines[i] );
 653
 654         if ( l > sizeof(psz_text) - total - 1 )
 655             l = sizeof(psz_text) - total - 1;
 656
 657         if ( l > 0 )
 658         {
 659             memcpy( pt, p_sys->ppsz_lines[i], l );
 660             total += l;
 661             pt += l;
 662             if ( sizeof(psz_text) - total - 1 > 0 )
 663             {
 664                 *pt++ = '\n';
 665                 total++;
 666             }
 667         }
 668     }
 669     *pt = 0;
 670
 671     if ( !strcmp(psz_text, p_sys->psz_prev_text) )
 672         goto error;
 673
 674     dbg((p_dec, "UPDATE TELETEXT PICTURE\n"));
 675
 676     assert( sizeof(p_sys->psz_prev_text) >= sizeof(psz_text) );
 677     strcpy( p_sys->psz_prev_text, psz_text );
 678
 679     /* Create the subpicture unit */
 680     p_spu = decoder_NewSubpicture( p_dec, NULL );
 681     if( !p_spu )
 682     {
 683         msg_Warn( p_dec, "can't get spu buffer" );
 684         goto error;
 685     }
 686
 687     /* Create a new subpicture region */
 688     video_format_Init(&fmt, VLC_CODEC_TEXT);
 689     fmt.i_width = fmt.i_height = 0;
 690     fmt.i_x_offset = fmt.i_y_offset = 0;
 691     p_spu->p_region = subpicture_region_New( &fmt );
 692     if( p_spu->p_region == NULL )
 693     {
 694         msg_Err( p_dec, "cannot allocate SPU region" );
 695         goto error;
 696     }
 697
 698     /* Normal text subs, easy markup */
 699     p_spu->p_region->i_align = SUBPICTURE_ALIGN_BOTTOM | p_sys->i_align;
 700     p_spu->p_region->i_x = p_sys->i_align ? 20 : 0;
 701     p_spu->p_region->i_y = 10;
 702     p_spu->p_region->p_text = text_segment_New(psz_text);
 703
 704     p_spu->i_start = p_block->i_pts;
 705     p_spu->i_stop = p_block->i_pts + p_block->i_length;
 706     p_spu->b_ephemer = (p_block->i_length == 0);
 707     p_spu->b_absolute = false;
 708     dbg((p_dec, "%ld --> %ld\n", (long int) p_block->i_pts/100000, (long int)p_block->i_length/100000));
 709
 710     block_Release( p_block );
 711     if( p_spu != NULL )
 712         decoder_QueueSub( p_dec, p_spu );
 713     return VLCDEC_SUCCESS;
 714
 715 error:
 716     if ( p_spu != NULL )
 717     {
 718         subpicture_Delete( p_spu );
 719         p_spu = NULL;
 720     }
 721
 722     block_Release( p_block );
 723     return VLCDEC_SUCCESS;
 724 }