2 * filter_data_feed.c -- data feed filter
3 * Copyright (C) 2004-2005 Ushodaya Enterprises Limited
4 * Author: Charles Yates <charles.yates@pandora.be>
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.
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.
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
23 #include <framework/mlt.h>
25 /** This filter should be used in conjuction with the data_show filter.
26 The concept of the data_feed is that it can be used to pass titles
27 or images to render on the frame, but doesn't actually do it
28 itself. data_feed imposes few rules on what's passed on and the
29 validity is confirmed in data_show before use.
32 /** Data queue destructor.
35 static void destroy_data_queue( void *arg
)
39 // Assign the correct type
40 mlt_deque queue
= arg
;
42 // Iterate through each item and destroy them
43 while ( mlt_deque_peek_front( queue
) != NULL
)
44 mlt_properties_close( mlt_deque_pop_back( queue
) );
47 mlt_deque_close( queue
);
51 /** Filter processing.
54 static mlt_frame
filter_process( mlt_filter
this, mlt_frame frame
)
56 // Get the filter properties
57 mlt_properties filter_properties
= MLT_FILTER_PROPERTIES( this );
59 // Get the frame properties
60 mlt_properties frame_properties
= MLT_FRAME_PROPERTIES( frame
);
63 mlt_deque data_queue
= mlt_properties_get_data( frame_properties
, "data_queue", NULL
);
65 // Get the type of the data feed
66 char *type
= mlt_properties_get( filter_properties
, "type" );
68 // Get the in and out points of this filter
69 int in
= mlt_filter_get_in( this );
70 int out
= mlt_filter_get_out( this );
72 // Create the data queue if it doesn't exist
73 if ( data_queue
== NULL
)
76 data_queue
= mlt_deque_init( );
78 // Assign it to the frame with the destructor
79 mlt_properties_set_data( frame_properties
, "data_queue", data_queue
, 0, destroy_data_queue
, NULL
);
82 // Now create the data feed
83 if ( data_queue
!= NULL
&& type
!= NULL
&& !strcmp( type
, "attr_check" ) )
86 int count
= mlt_properties_count( frame_properties
);
88 for ( i
= 0; i
< count
; i
++ )
90 char *name
= mlt_properties_get_name( frame_properties
, i
);
92 // Only deal with meta.attr.name values here - these should have a value of 1 to be considered
93 // Additional properties of the form are meta.attr.name.property are passed down on the feed
94 if ( !strncmp( name
, "meta.attr.", 10 ) && strchr( name
+ 10, '.' ) == NULL
&& mlt_properties_get_int( frame_properties
, name
) == 1 )
96 // Temp var to hold name + '.' for pass method
99 // Create a new data feed
100 mlt_properties feed
= mlt_properties_new( );
102 // Assign it the base properties
103 mlt_properties_set( feed
, "id", mlt_properties_get( filter_properties
, "_unique_id" ) );
104 mlt_properties_set( feed
, "type", strrchr( name
, '.' ) + 1 );
105 mlt_properties_set_position( feed
, "position", mlt_frame_get_position( frame
) );
107 // Assign in/out of service we're connected to
108 mlt_properties_set_position( feed
, "in", mlt_properties_get_position( frame_properties
, "in" ) );
109 mlt_properties_set_position( feed
, "out", mlt_properties_get_position( frame_properties
, "out" ) );
111 // Pass all meta properties
112 sprintf( temp
, "%s.", name
);
113 mlt_properties_pass( feed
, frame_properties
, temp
);
115 // Push it on to the queue
116 mlt_deque_push_back( data_queue
, feed
);
118 // Make sure this attribute only gets processed once
119 mlt_properties_set_int( frame_properties
, name
, 0 );
123 else if ( data_queue
!= NULL
)
125 // Create a new data feed
126 mlt_properties feed
= mlt_properties_new( );
128 // Assign it the base properties
129 mlt_properties_set( feed
, "id", mlt_properties_get( filter_properties
, "_unique_id" ) );
130 mlt_properties_set( feed
, "type", type
);
131 mlt_properties_set_position( feed
, "position", mlt_frame_get_position( frame
) );
133 // Assign in/out of service we're connected to
134 mlt_properties_set_position( feed
, "in", mlt_properties_get_position( frame_properties
, "in" ) );
135 mlt_properties_set_position( feed
, "out", mlt_properties_get_position( frame_properties
, "out" ) );
137 // Correct in/out to the filter if specified
139 mlt_properties_set_position( feed
, "in", in
);
141 mlt_properties_set_position( feed
, "out", out
);
143 // Pass the properties which start with a "feed." prefix
144 // Note that 'feed.text' in the filter properties becomes 'text' on the feed
145 mlt_properties_pass( feed
, filter_properties
, "feed." );
147 // Push it on to the queue
148 mlt_deque_push_back( data_queue
, feed
);
154 /** Constructor for the filter.
157 mlt_filter
filter_data_feed_init( mlt_profile profile
, mlt_service_type type
, const char *id
, char *arg
)
160 mlt_filter
this = mlt_filter_new( );
165 // Get the properties
166 mlt_properties properties
= MLT_FILTER_PROPERTIES( this );
168 // Assign the argument (default to titles)
169 mlt_properties_set( properties
, "type", arg
== NULL ?
"titles" : arg
);
171 // Specify the processing method
172 this->process
= filter_process
;