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 // Define the destructor
48 service->close = ( mlt_destructor )mlt_filter_close;
49 service->close_object = this;
51 // Default in, out, track properties
52 mlt_properties_set_position( properties, "in", 0 );
53 mlt_properties_set_position( properties, "out", 0 );
54 mlt_properties_set_int( properties, "track", 0 );
61 /** Create a new filter.
64 mlt_filter mlt_filter_new( )
66 mlt_filter this = calloc( 1, sizeof( struct mlt_filter_s ) );
68 mlt_filter_init( this, NULL );
72 /** Get the service associated to this filter
75 mlt_service mlt_filter_service( mlt_filter this )
77 return this != NULL ? &this->parent : NULL;
80 /** Get the properties associated to this filter.
83 mlt_properties mlt_filter_properties( mlt_filter this )
85 return MLT_SERVICE_PROPERTIES( MLT_FILTER_SERVICE( this ) );
88 /** Connect this filter to a producers track. Note that a filter only operates
89 on a single track, and by default it operates on the entirety of that track.
92 int mlt_filter_connect( mlt_filter this, mlt_service producer, int index )
94 int ret = mlt_service_connect_producer( &this->parent, producer, index );
96 // If the connection was successful, grab the producer, track and reset in/out
99 mlt_properties properties = MLT_SERVICE_PROPERTIES( &this->parent );
100 mlt_properties_set_position( properties, "in", 0 );
101 mlt_properties_set_position( properties, "out", 0 );
102 mlt_properties_set_int( properties, "track", index );
108 /** Tune the in/out points.
111 void mlt_filter_set_in_and_out( mlt_filter this, mlt_position in, mlt_position out )
113 mlt_properties properties = MLT_SERVICE_PROPERTIES( &this->parent );
114 mlt_properties_set_position( properties, "in", in );
115 mlt_properties_set_position( properties, "out", out );
118 /** Return the track that this filter is operating on.
121 int mlt_filter_get_track( mlt_filter this )
123 mlt_properties properties = MLT_SERVICE_PROPERTIES( &this->parent );
124 return mlt_properties_get_int( properties, "track" );
127 /** Get the in point.
130 mlt_position mlt_filter_get_in( mlt_filter this )
132 mlt_properties properties = MLT_SERVICE_PROPERTIES( &this->parent );
133 return mlt_properties_get_position( properties, "in" );
136 /** Get the out point.
139 mlt_position mlt_filter_get_out( mlt_filter this )
141 mlt_properties properties = MLT_SERVICE_PROPERTIES( &this->parent );
142 return mlt_properties_get_position( properties, "out" );
145 /** Process the frame.
148 mlt_frame mlt_filter_process( mlt_filter this, mlt_frame frame )
150 int disable = mlt_properties_get_int( MLT_FILTER_PROPERTIES( this ), "disable" );
151 if ( disable || this->process == NULL )
154 return this->process( this, frame );
157 /** Get a frame from this filter.
160 static int filter_get_frame( mlt_service service, mlt_frame_ptr frame, int index )
162 mlt_filter this = service->child;
164 // Get coords in/out/track
165 int track = mlt_filter_get_track( this );
166 int in = mlt_filter_get_in( this );
167 int out = mlt_filter_get_out( this );
169 // Get the producer this is connected to
170 mlt_service producer = mlt_service_producer( &this->parent );
172 // If the frame request is for this filters track, we need to process it
173 if ( index == track || track == -1 )
175 int ret = mlt_service_get_frame( producer, frame, index );
178 mlt_position position = mlt_frame_get_position( *frame );
179 if ( position >= in && ( out == 0 || position <= out ) )
180 *frame = mlt_filter_process( this, *frame );
185 *frame = mlt_frame_init( );
191 return mlt_service_get_frame( producer, frame, index );
195 /** Close the filter.
198 void mlt_filter_close( mlt_filter this )
200 if ( this != NULL && mlt_properties_dec_ref( MLT_FILTER_PROPERTIES( this ) ) <= 0 )
202 if ( this->close != NULL )
208 this->parent.close = NULL;
209 mlt_service_close( &this->parent );