1 /*****************************************************************************
2 * langfromtelx.c: dynamic language setting from telx
3 *****************************************************************************
4 * Copyright (C) 2009, 2011 VideoLAN
7 * Authors: Christophe Massiot <massiot@via.ecp.fr>
9 * This program is free software; you can redistribute it and/or modify
10 * it 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.
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 General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
33 #include <vlc_common.h>
34 #include <vlc_plugin.h>
36 #include <vlc_block.h>
38 /*****************************************************************************
40 *****************************************************************************/
42 #define ID_TEXT N_("Elementary Stream ID")
43 #define ID_LONGTEXT N_( \
44 "Specify an identifier integer for this elementary stream to change" )
45 #define MAGAZINE_TEXT N_("Magazine")
46 #define MAGAZINE_LONGTEXT N_( \
47 "Specify the magazine containing the language page" )
48 #define PAGE_TEXT N_("Page")
49 #define PAGE_LONGTEXT N_( \
50 "Specify the page containing the language" )
51 #define ROW_TEXT N_("Row")
52 #define ROW_LONGTEXT N_( \
53 "Specify the row containing the language" )
55 static int Open ( vlc_object_t
* );
56 static void Close ( vlc_object_t
* );
58 #define SOUT_CFG_PREFIX "sout-langfromtelx-"
61 set_shortname( N_("Lang From Telx"))
62 set_description( N_("Dynamic language setting from teletext"))
63 set_capability( "sout stream", 50 )
64 add_shortcut( "langfromtelx" )
65 set_category( CAT_SOUT
)
66 set_subcategory( SUBCAT_SOUT_STREAM
)
68 set_callbacks( Open
, Close
)
69 add_integer( SOUT_CFG_PREFIX
"id", 0, ID_TEXT
, ID_LONGTEXT
,
71 add_integer( SOUT_CFG_PREFIX
"magazine", 7, MAGAZINE_TEXT
,
72 MAGAZINE_LONGTEXT
, false )
73 add_integer( SOUT_CFG_PREFIX
"page", 0x99, PAGE_TEXT
, PAGE_LONGTEXT
,
75 add_integer( SOUT_CFG_PREFIX
"row", 1, ROW_TEXT
, ROW_LONGTEXT
,
80 /*****************************************************************************
82 *****************************************************************************/
83 static const char *ppsz_sout_options
[] = {
84 "id", "magazine", "page", "row", NULL
87 static sout_stream_id_t
*Add ( sout_stream_t
*, es_format_t
* );
88 static int Del ( sout_stream_t
*, sout_stream_id_t
* );
89 static int Send ( sout_stream_t
*, sout_stream_id_t
*, block_t
* );
91 struct sout_stream_sys_t
93 int i_id
, i_magazine
, i_page
, i_row
;
94 char *psz_language
, *psz_old_language
;
95 sout_stream_id_t
*p_id
, *p_telx
;
99 /*****************************************************************************
101 *****************************************************************************/
102 static int Open( vlc_object_t
*p_this
)
104 sout_stream_t
*p_stream
= (sout_stream_t
*)p_this
;
105 sout_stream_sys_t
*p_sys
;
107 if( !p_stream
->p_next
)
109 msg_Err( p_stream
, "cannot create chain" );
113 p_sys
= malloc( sizeof( sout_stream_sys_t
) );
114 if( unlikely( !p_sys
) )
117 config_ChainParse( p_stream
, SOUT_CFG_PREFIX
, ppsz_sout_options
,
120 p_sys
->i_id
= var_GetInteger( p_stream
, SOUT_CFG_PREFIX
"id" );
121 p_sys
->i_magazine
= var_GetInteger( p_stream
, SOUT_CFG_PREFIX
"magazine" );
122 p_sys
->i_page
= var_GetInteger( p_stream
, SOUT_CFG_PREFIX
"page" );
123 p_sys
->i_row
= var_GetInteger( p_stream
, SOUT_CFG_PREFIX
"row" );
125 p_stream
->pf_add
= Add
;
126 p_stream
->pf_del
= Del
;
127 p_stream
->pf_send
= Send
;
129 p_stream
->p_sys
= p_sys
;
134 /*****************************************************************************
136 *****************************************************************************/
137 static void Close( vlc_object_t
* p_this
)
139 sout_stream_t
*p_stream
= (sout_stream_t
*)p_this
;
140 sout_stream_sys_t
*p_sys
= (sout_stream_sys_t
*)p_stream
->p_sys
;
142 free( p_sys
->psz_old_language
);
146 static sout_stream_id_t
* Add( sout_stream_t
*p_stream
, es_format_t
*p_fmt
)
148 sout_stream_sys_t
*p_sys
= (sout_stream_sys_t
*)p_stream
->p_sys
;
150 if ( p_fmt
->i_id
== p_sys
->i_id
)
152 p_sys
->psz_old_language
= p_fmt
->psz_language
;
154 "changing language of ID %d (magazine %d page %x row %d)",
155 p_sys
->i_id
, p_sys
->i_magazine
, p_sys
->i_page
, p_sys
->i_row
);
156 p_sys
->psz_language
= p_fmt
->psz_language
= malloc(4);
157 if ( p_sys
->psz_old_language
!= NULL
)
158 strncpy( p_fmt
->psz_language
, p_sys
->psz_old_language
, 3 );
160 strcpy( p_fmt
->psz_language
, "unk" );
161 p_fmt
->psz_language
[3] = '\0';
163 p_sys
->p_id
= p_stream
->p_next
->pf_add( p_stream
->p_next
, p_fmt
);
167 if ( p_fmt
->i_codec
== VLC_CODEC_TELETEXT
)
169 p_sys
->p_telx
= p_stream
->p_next
->pf_add( p_stream
->p_next
, p_fmt
);
170 return p_sys
->p_telx
;
173 return p_stream
->p_next
->pf_add( p_stream
->p_next
, p_fmt
);
176 static int Del( sout_stream_t
*p_stream
, sout_stream_id_t
*id
)
178 sout_stream_sys_t
*p_sys
= (sout_stream_sys_t
*)p_stream
->p_sys
;
180 if ( id
== p_sys
->p_id
) p_sys
->p_id
= NULL
;
181 if ( id
== p_sys
->p_telx
) p_sys
->p_telx
= NULL
;
183 return p_stream
->p_next
->pf_del( p_stream
->p_next
, id
);
186 static void SetLanguage( sout_stream_t
*p_stream
, char *psz_language
)
188 sout_stream_sys_t
*p_sys
= (sout_stream_sys_t
*)p_stream
->p_sys
;
190 if ( strncmp( p_sys
->psz_language
, psz_language
, 3 ) )
191 msg_Dbg( p_stream
, "changing language to %s", psz_language
);
193 strncpy( p_sys
->psz_language
, psz_language
, 3 );
196 /*****************************************************************************
198 *****************************************************************************/
199 static uint8_t bytereverse( int n
)
201 n
= (((n
>> 1) & 0x55) | ((n
<< 1) & 0xaa));
202 n
= (((n
>> 2) & 0x33) | ((n
<< 2) & 0xcc));
203 n
= (((n
>> 4) & 0x0f) | ((n
<< 4) & 0xf0));
207 static int hamming_8_4( int a
)
243 return -1; // decoding error , not yet corrected
247 static void decode_string( char *res
, uint8_t *packet
, int len
)
249 for ( int i
= 0; i
< len
; i
++ )
250 res
[i
] = bytereverse( packet
[i
] ) & 0x7f;
255 static void HandleTelx( sout_stream_t
*p_stream
, block_t
*p_block
)
257 sout_stream_sys_t
*p_sys
= (sout_stream_sys_t
*)p_stream
->p_sys
;
258 int len
= p_block
->i_buffer
;
260 for ( int offset
= 1; offset
+ 46 <= len
; offset
+= 46 )
262 uint8_t * packet
= (uint8_t *) p_block
->p_buffer
+offset
;
263 if ( packet
[0] == 0xFF )
266 int mpag
= (hamming_8_4( packet
[4] ) << 4) | hamming_8_4( packet
[5] );
267 int i_row
, i_magazine
;
274 i_row
= 0xFF & bytereverse(mpag
);
275 i_magazine
= (7 & i_row
) == 0 ? 8 : (7 & i_row
);
278 if ( i_magazine
!= p_sys
->i_magazine
)
283 /* row 0 : flags and header line */
284 p_sys
->i_current_page
=
285 (0xF0 & bytereverse( hamming_8_4(packet
[7]) )) |
286 (0xF & (bytereverse( hamming_8_4(packet
[6]) ) >> 4) );
288 if ( p_sys
->i_current_page
!= p_sys
->i_page
) continue;
289 if ( i_row
== p_sys
->i_row
)
291 /* row 1-23 : normal lines */
293 decode_string( psz_line
, packet
+ 6, 40 );
294 psz_line
[0] = tolower(psz_line
[0]);
295 psz_line
[1] = tolower(psz_line
[1]);
296 psz_line
[2] = tolower(psz_line
[2]);
298 SetLanguage( p_stream
, psz_line
);
303 /*****************************************************************************
305 *****************************************************************************/
306 static int Send( sout_stream_t
*p_stream
, sout_stream_id_t
*id
,
309 sout_stream_sys_t
*p_sys
= (sout_stream_sys_t
*)p_stream
->p_sys
;
311 if ( id
== p_sys
->p_telx
)
312 HandleTelx( p_stream
, p_buffer
);
314 return p_stream
->p_next
->pf_send( p_stream
->p_next
, id
, p_buffer
);