2 * mlt_tractor.c -- tractor service class
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_tractor.h"
24 #include "mlt_frame.h"
25 #include "mlt_multitrack.h"
30 /** Private structure.
35 struct mlt_producer_s parent;
39 /** Forward references to static methods.
42 static int producer_get_frame( mlt_producer this, mlt_frame_ptr frame, int track );
44 /** Constructor for the tractor.
46 TODO: thread this service...
49 mlt_tractor mlt_tractor_init( )
51 mlt_tractor this = calloc( sizeof( struct mlt_tractor_s ), 1 );
54 mlt_producer producer = &this->parent;
55 if ( mlt_producer_init( producer, this ) == 0 )
57 producer->get_frame = producer_get_frame;
68 /** Get the service object associated to the tractor.
71 mlt_service mlt_tractor_service( mlt_tractor this )
73 return mlt_producer_service( &this->parent );
76 /** Get the producer object associated to the tractor.
79 mlt_producer mlt_tractor_producer( mlt_tractor this )
84 /** Get the properties object associated to the tractor.
87 mlt_properties mlt_tractor_properties( mlt_tractor this )
89 return mlt_producer_properties( &this->parent );
92 /** Connect the tractor.
95 int mlt_tractor_connect( mlt_tractor this, mlt_service producer )
97 int ret = mlt_service_connect_producer( mlt_tractor_service( this ), producer, 0 );
99 // This is the producer we're going to connect to
101 this->producer = producer;
106 /** Get the next frame.
108 TODO: This should be reading a pump being populated by the thread...
111 static int producer_get_frame( mlt_producer parent, mlt_frame_ptr frame, int track )
113 mlt_tractor this = parent->child;
115 // We only respond to the first track requests
116 if ( track == 0 && this->producer != NULL )
121 mlt_frame temp = NULL;
123 // Get the properties of the parent producer
124 mlt_properties properties = mlt_producer_properties( parent );
126 // Try to obtain the multitrack associated to the tractor
127 mlt_multitrack multitrack = mlt_properties_get_data( properties, "multitrack", NULL );
129 // If we don't have one, we're in trouble...
130 if ( multitrack != NULL )
132 mlt_producer target = mlt_multitrack_producer( multitrack );
133 mlt_producer_seek( target, mlt_producer_frame( parent ) );
134 mlt_producer_set_speed( target, mlt_producer_get_speed( parent ) );
135 mlt_producer_set_in_and_out( parent, mlt_producer_get_in( target ), mlt_producer_get_out( target ) );
139 fprintf( stderr, "tractor without a multitrack!!\n" );
142 // Loop through each of the tracks we're harvesting
143 for ( i = 0; !done; i ++ )
145 // Get a frame from the producer
146 mlt_service_get_frame( this->producer, &temp, i );
148 // Check for last track
149 done = mlt_properties_get_int( mlt_frame_properties( temp ), "last_track" );
152 if ( done && looking )
154 // Use this as output if we don't have one already
157 else if ( ( !mlt_frame_is_test_card( temp ) || !mlt_frame_is_test_audio( temp ) ) &&
158 mlt_producer_frame( parent ) == mlt_properties_get_position( mlt_frame_properties( temp ), "position" ) )
163 else if ( ( !mlt_frame_is_test_card( temp ) || !mlt_frame_is_test_audio( temp ) ) && looking )
165 // This is the one we want and we can stop looking
171 // We discard all other frames
172 mlt_frame_close( temp );
176 // Prepare the next frame
177 mlt_producer_prepare_next( parent );
179 // Indicate our found status
184 // Generate a test card
185 *frame = mlt_frame_init( );
190 /** Close the tractor.
193 void mlt_tractor_close( mlt_tractor this )
195 mlt_producer_close( &this->parent );