1 /*****************************************************************************
2 * cdg.c : cdg file demux module for vlc
3 *****************************************************************************
4 * Copyright (C) 2007 Laurent Aimar
5 * $Id: c36bac34887a05f67f56e5d0bbf23873075a2fdb $
6 *
7 * Authors: Laurent Aimar <fenrir # via.ecp.fr>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU Lesser General Public License as published by
11 * the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this program; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
23
24 /*****************************************************************************
25 * Preamble
26 *****************************************************************************/
27
28 #ifdef HAVE_CONFIG_H
29 # include "config.h"
30 #endif
31
32 #include <vlc_common.h>
33 #include <vlc_plugin.h>
34 #include <vlc_demux.h>
35
36 /*****************************************************************************
37 * Module descriptor
38 *****************************************************************************/
39 static int Open ( vlc_object_t * );
40 static void Close( vlc_object_t * );
41
42 vlc_module_begin ()
43 set_description( N_("CDG demuxer") )
44 set_category( CAT_INPUT )
45 set_subcategory( SUBCAT_INPUT_DEMUX )
46 set_capability( "demux", 3 )
47 set_callbacks( Open, Close )
48 add_shortcut( "cdg", "subtitle" )
49 vlc_module_end ()
50
51 /*****************************************************************************
52 * Local prototypes
53 *****************************************************************************/
54 static int Demux ( demux_t * );
55 static int Control( demux_t *, int i_query, va_list args );
56
57 struct demux_sys_t
58 {
59 es_format_t fmt;
60 es_out_id_t *p_es;
61
62 date_t pts;
63 };
64
65 #define CDG_FRAME_SIZE (96)
66 #define CDG_FRAME_RATE (75)
67
68 /*****************************************************************************
69 * Open: check file and initializes structures
70 *****************************************************************************/
Open(vlc_object_t * p_this)71 static int Open( vlc_object_t * p_this )
72 {
73 demux_t *p_demux = (demux_t*)p_this;
74 demux_sys_t *p_sys;
75
76 /* Identify cdg file by extension, as there is no simple way to
77 * detect it */
78 if( !demux_IsPathExtension( p_demux, ".cdg" ) && !demux_IsForced( p_demux, "cdg" ) )
79 return VLC_EGENERIC;
80
81 /* CDG file size has to be multiple of CDG_FRAME_SIZE (it works even
82 * if size is unknown ie 0) */
83 // if( (stream_Size( p_demux->s ) % CDG_FRAME_SIZE) != 0 )
84 // {
85 // msg_Err( p_demux, "Reject CDG file based on its size" );
86 // return VLC_EGENERIC;
87 // }
88
89 p_sys = malloc( sizeof( demux_sys_t ) );
90 if( unlikely(p_sys == NULL) )
91 return VLC_ENOMEM;
92
93 p_demux->pf_demux = Demux;
94 p_demux->pf_control = Control;
95 p_demux->p_sys = p_sys;
96
97 /* */
98 es_format_Init( &p_sys->fmt, VIDEO_ES, VLC_CODEC_CDG );
99 p_sys->fmt.video.i_width = 300-2*6;
100 p_sys->fmt.video.i_height = 216-2*12 ;
101 p_sys->fmt.video.i_visible_width = p_sys->fmt.video.i_width;
102 p_sys->fmt.video.i_visible_height = p_sys->fmt.video.i_height;
103
104 p_sys->p_es = es_out_Add( p_demux->out, &p_sys->fmt );
105
106 /* There is CDG_FRAME_RATE frames per second */
107 date_Init( &p_sys->pts, CDG_FRAME_RATE, 1 );
108 date_Set( &p_sys->pts, 0 );
109
110 return VLC_SUCCESS;
111 }
112
113 /*****************************************************************************
114 * Demux: read packet and send them to decoders
115 *****************************************************************************
116 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
117 *****************************************************************************/
Demux(demux_t * p_demux)118 static int Demux( demux_t *p_demux )
119 {
120 demux_sys_t *p_sys = p_demux->p_sys;
121 block_t *p_block;
122 mtime_t i_date;
123 mtime_t i_delta;
124
125 i_delta = INT64_C(1000000) / CDG_FRAME_RATE;
126
127 p_block = vlc_stream_Block( p_demux->s, CDG_FRAME_SIZE );
128 if( p_block == NULL )
129 {
130 msg_Dbg( p_demux, "cannot read data, eof" );
131 return 0;
132 }
133
134 i_date = vlc_stream_Tell( p_demux->s ) / CDG_FRAME_SIZE * i_delta;
135 if( i_date >= date_Get( &p_sys->pts ) + i_delta )
136 {
137 p_block->i_dts = p_block->i_pts = i_date;
138 date_Set( &p_sys->pts, i_date );
139 }
140 else
141 {
142 p_block->i_dts = i_date;
143 p_block->i_pts = date_Get( &p_sys->pts );
144 }
145
146 es_out_SetPCR( p_demux->out, p_block->i_pts );
147
148 es_out_Send( p_demux->out, p_sys->p_es, p_block );
149
150 return 1;
151 }
152
153 /*****************************************************************************
154 * Close: frees unused data
155 *****************************************************************************/
Close(vlc_object_t * p_this)156 static void Close ( vlc_object_t * p_this )
157 {
158 demux_t *p_demux = (demux_t *)p_this;
159 demux_sys_t *p_sys = p_demux->p_sys;
160
161 free( p_sys );
162 }
163
164 /*****************************************************************************
165 * Control:
166 *****************************************************************************/
Control(demux_t * p_demux,int i_query,va_list args)167 static int Control( demux_t *p_demux, int i_query, va_list args )
168 {
169 uint64_t i_old_offset = vlc_stream_Tell( p_demux->s );
170 int i_ret = demux_vaControlHelper( p_demux->s, 0, -1,
171 8*CDG_FRAME_SIZE*CDG_FRAME_RATE, CDG_FRAME_SIZE,
172 i_query, args );
173 if( !i_ret && ( i_query == DEMUX_SET_POSITION || i_query == DEMUX_SET_TIME ) )
174 {
175 date_Set( &p_demux->p_sys->pts,
176 vlc_stream_Tell( p_demux->s ) / CDG_FRAME_SIZE *
177 INT64_C(1000000) / CDG_FRAME_RATE );
178 if ( i_old_offset > vlc_stream_Tell( p_demux->s ) )
179 i_ret = vlc_stream_Seek( p_demux->s, 0 );
180 else
181 i_ret = vlc_stream_Seek( p_demux->s, i_old_offset );
182 }
183
184 return i_ret;
185 }
186
187