2 * mlt_filter.c -- abstraction for all filter services
3 * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
4 * Author: Charles Yates <charles.yates@pandora.be>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program 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
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software Foundation,
18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 #include "mlt_filter.h"
24 #include "mlt_frame.h"
30 static int filter_get_frame( mlt_service this, mlt_frame_ptr frame, int index );
32 /** Constructor method.
35 int mlt_filter_init( mlt_filter this, void *child )
37 mlt_service service = &this->parent;
38 memset( this, 0, sizeof( struct mlt_filter_s ) );
40 if ( mlt_service_init( service, this ) == 0 )
42 mlt_properties properties = mlt_service_properties( service );
44 // Override the get_frame method
45 service->get_frame = filter_get_frame;
47 // Default in, out, track properties
48 mlt_properties_set_position( properties, "in", 0 );
49 mlt_properties_set_position( properties, "out", 0 );
50 mlt_properties_set_int( properties, "track", 0 );
57 /** Get the service associated to this filter
60 mlt_service mlt_filter_service( mlt_filter this )
65 mlt_properties mlt_filter_properties( mlt_filter this )
67 return mlt_service_properties( mlt_filter_service( this ) );
70 /** Connect this filter to a producers track. Note that a filter only operates
71 on a single track, and by default it operates on the entirety of that track.
74 int mlt_filter_connect( mlt_filter this, mlt_service producer, int index )
76 int ret = mlt_service_connect_producer( &this->parent, producer, index );
78 // If the connection was successful, grab the producer, track and reset in/out
81 mlt_properties properties = mlt_service_properties( &this->parent );
82 this->producer = producer;
83 mlt_properties_set_position( properties, "in", 0 );
84 mlt_properties_set_position( properties, "out", 0 );
85 mlt_properties_set_int( properties, "track", index );
91 /** Tune the in/out points.
94 void mlt_filter_set_in_and_out( mlt_filter this, mlt_position in, mlt_position out )
96 mlt_properties properties = mlt_service_properties( &this->parent );
97 mlt_properties_set_position( properties, "in", in );
98 mlt_properties_set_position( properties, "out", out );
101 /** Return the track that this filter is operating on.
104 int mlt_filter_get_track( mlt_filter this )
106 mlt_properties properties = mlt_service_properties( &this->parent );
107 return mlt_properties_get_int( properties, "track" );
110 /** Get the in point.
113 mlt_position mlt_filter_get_in( mlt_filter this )
115 mlt_properties properties = mlt_service_properties( &this->parent );
116 return mlt_properties_get_position( properties, "in" );
119 /** Get the out point.
122 mlt_position mlt_filter_get_out( mlt_filter this )
124 mlt_properties properties = mlt_service_properties( &this->parent );
125 return mlt_properties_get_position( properties, "out" );
128 /** Process the frame.
131 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
133 if ( this->process == NULL )
136 return this->process( this, frame );
139 /** Get a frame from this filter.
142 static int filter_get_frame( mlt_service service, mlt_frame_ptr frame, int index )
144 mlt_filter this = service->child;
146 // Get coords in/out/track
147 int track = mlt_filter_get_track( this );
148 int in = mlt_filter_get_in( this );
149 int out = mlt_filter_get_out( this );
151 // If the frame request is for this filters track, we need to process it
152 if ( index == track )
154 int ret = mlt_service_get_frame( this->producer, frame, index );
157 if ( !mlt_frame_is_test_card( *frame ) )
159 mlt_position position = mlt_frame_get_position( *frame );
160 if ( position >= in && ( out == 0 || position < out ) )
161 *frame = filter_process( this, *frame );
167 *frame = mlt_frame_init( );
173 return mlt_service_get_frame( this->producer, frame, index );
177 /** Close the filter.
180 void mlt_filter_close( mlt_filter this )
182 if ( this->close != NULL )
185 mlt_service_close( &this->parent );