2 * mlt_service.c -- interface for all service classes
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.
22 #include "mlt_service.h"
23 #include "mlt_filter.h"
24 #include "mlt_frame.h"
31 The base service implements a null frame producing service - as such,
32 it is functional without extension and will produce test cards frames
33 and PAL sized audio frames.
35 PLEASE DO NOT CHANGE THIS BEHAVIOUR!!! OVERRIDE THE METHODS THAT
36 CONTROL THIS IN EXTENDING CLASSES.
39 /** Private service definition.
57 static void mlt_service_disconnect( mlt_service this );
58 static void mlt_service_connect( mlt_service this, mlt_service that );
59 static int service_get_frame( mlt_service this, mlt_frame_ptr frame, int index );
60 static void mlt_service_property_changed( mlt_listener, mlt_properties owner, mlt_service this, void **args );
65 int mlt_service_init( mlt_service this, void *child )
69 // Initialise everything to NULL
70 memset( this, 0, sizeof( struct mlt_service_s ) );
75 // Generate local space
76 this->local = calloc( sizeof( mlt_service_base ), 1 );
78 // Associate the methods
79 this->get_frame = service_get_frame;
81 // Initialise the properties
82 error = mlt_properties_init( &this->parent, this );
85 this->parent.close = ( mlt_destructor )mlt_service_close;
86 this->parent.close_object = this;
88 mlt_events_init( &this->parent );
89 mlt_events_register( &this->parent, "service-changed", NULL );
90 mlt_events_register( &this->parent, "property-changed", ( mlt_transmitter )mlt_service_property_changed );
96 static void mlt_service_property_changed( mlt_listener listener, mlt_properties owner, mlt_service this, void **args )
98 if ( listener != NULL )
99 listener( owner, this, ( char * )args[ 0 ] );
102 /** Connect a producer service.
103 Returns: > 0 warning, == 0 success, < 0 serious error
104 1 = this service does not accept input
105 2 = the producer is invalid
106 3 = the producer is already registered with this consumer
109 int mlt_service_connect_producer( mlt_service this, mlt_service producer, int index )
113 // Get the service base
114 mlt_service_base *base = this->local;
116 // Check if the producer is already registered with this service
117 for ( i = 0; i < base->count; i ++ )
118 if ( base->in[ i ] == producer )
122 if ( index >= base->size )
124 int new_size = base->size + index + 10;
125 base->in = realloc( base->in, new_size * sizeof( mlt_service ) );
126 if ( base->in != NULL )
128 for ( i = base->size; i < new_size; i ++ )
129 base->in[ i ] = NULL;
130 base->size = new_size;
134 // If we have space, assign the input
135 if ( base->in != NULL && index >= 0 && index < base->size )
137 // Get the current service
138 mlt_service current = base->in[ index ];
140 // Increment the reference count on this producer
141 if ( producer != NULL )
142 mlt_properties_inc_ref( mlt_service_properties( producer ) );
144 // Now we disconnect the producer service from its consumer
145 mlt_service_disconnect( producer );
147 // Add the service to index specified
148 base->in[ index ] = producer;
150 // Determine the number of active tracks
151 if ( index >= base->count )
152 base->count = index + 1;
154 // Now we connect the producer to its connected consumer
155 mlt_service_connect( producer, this );
157 // Close the current service
158 mlt_service_close( current );
160 // Inform caller that all went well
169 /** Disconnect this service from its consumer.
172 static void mlt_service_disconnect( mlt_service this )
176 // Get the service base
177 mlt_service_base *base = this->local;
184 /** Obtain the consumer this service is connected to.
187 mlt_service mlt_service_consumer( mlt_service this )
189 // Get the service base
190 mlt_service_base *base = this->local;
192 // Return the connected consumer
196 /** Obtain the producer this service is connected to.
199 mlt_service mlt_service_producer( mlt_service this )
201 // Get the service base
202 mlt_service_base *base = this->local;
204 // Return the connected producer
205 return base->count > 0 ? base->in[ base->count - 1 ] : NULL;
208 /** Associate this service to the consumer.
211 static void mlt_service_connect( mlt_service this, mlt_service that )
215 // Get the service base
216 mlt_service_base *base = this->local;
218 // There's a bit more required here...
223 /** Get the first connected producer service.
226 mlt_service mlt_service_get_producer( mlt_service this )
228 mlt_service producer = NULL;
230 // Get the service base
231 mlt_service_base *base = this->local;
233 if ( base->in != NULL )
234 producer = base->in[ 0 ];
239 /** Default implementation of get_frame.
242 static int service_get_frame( mlt_service this, mlt_frame_ptr frame, int index )
244 mlt_service_base *base = this->local;
245 if ( index < base->count )
247 mlt_service producer = base->in[ index ];
248 if ( producer != NULL )
249 return mlt_service_get_frame( producer, frame, index );
251 *frame = mlt_frame_init( );
255 /** Return the properties object.
258 mlt_properties mlt_service_properties( mlt_service self )
260 return self != NULL ? &self->parent : NULL;
263 /** Recursively apply attached filters
266 static void apply_filters( mlt_service this, mlt_frame frame, int index )
268 mlt_properties properties = mlt_service_properties( this );
269 mlt_service_base *base = this->local;
272 if ( mlt_properties_get_int( properties, "_filter_private" ) == 0 )
274 // Process the frame with the attached filters
275 for ( i = 0; i < base->filter_count; i ++ )
277 if ( base->filters[ i ] != NULL )
279 mlt_filter_process( base->filters[ i ], frame );
280 apply_filters( mlt_filter_service( base->filters[ i ] ), frame, index );
289 int mlt_service_get_frame( mlt_service this, mlt_frame_ptr frame, int index )
293 int result = this->get_frame( this, frame, index );
295 apply_filters( this, *frame, index );
298 *frame = mlt_frame_init( );
302 static void mlt_service_filter_changed( mlt_service owner, mlt_service this )
304 mlt_events_fire( mlt_service_properties( this ), "service-changed", NULL );
310 int mlt_service_attach( mlt_service this, mlt_filter filter )
312 int error = this == NULL || filter == NULL;
316 mlt_properties properties = mlt_service_properties( this );
317 mlt_service_base *base = this->local;
319 for ( i = 0; error == 0 && i < base->filter_count; i ++ )
320 if ( base->filters[ i ] == filter )
325 if ( base->filter_count == base->filter_size )
327 base->filter_size += 10;
328 base->filters = realloc( base->filters, base->filter_size * sizeof( mlt_filter ) );
331 if ( base->filters != NULL )
333 mlt_properties props = mlt_filter_properties( filter );
334 mlt_properties_inc_ref( mlt_filter_properties( filter ) );
335 base->filters[ base->filter_count ++ ] = filter;
336 mlt_events_fire( properties, "service-changed", NULL );
337 mlt_events_listen( props, this, "service-changed", ( mlt_listener )mlt_service_filter_changed );
338 mlt_events_listen( props, this, "property-changed", ( mlt_listener )mlt_service_filter_changed );
352 int mlt_service_detach( mlt_service this, mlt_filter filter )
354 int error = this == NULL || filter == NULL;
358 mlt_service_base *base = this->local;
359 mlt_properties properties = mlt_service_properties( this );
361 for ( i = 0; i < base->filter_count; i ++ )
362 if ( base->filters[ i ] == filter )
365 if ( i < base->filter_count )
367 base->filters[ i ] = NULL;
368 for ( i ++ ; i < base->filter_count; i ++ )
369 base->filters[ i - 1 ] = base->filters[ i ];
370 base->filter_count --;
371 mlt_events_disconnect( mlt_filter_properties( filter ), this );
372 mlt_filter_close( filter );
373 mlt_events_fire( properties, "service-changed", NULL );
379 /** Retrieve a filter.
382 mlt_filter mlt_service_filter( mlt_service this, int index )
384 mlt_filter filter = NULL;
387 mlt_service_base *base = this->local;
388 if ( index >= 0 && index < base->filter_count )
389 filter = base->filters[ index ];
394 /** Close the service.
397 void mlt_service_close( mlt_service this )
399 if ( this != NULL && mlt_properties_dec_ref( mlt_service_properties( this ) ) <= 0 )
401 if ( this->close != NULL )
403 this->close( this->close_object );
407 mlt_service_base *base = this->local;
409 int count = base->filter_count;
410 mlt_events_block( mlt_service_properties( this ), this );
412 mlt_service_detach( this, base->filters[ 0 ] );
413 free( base->filters );
414 for ( i = 0; i < base->count; i ++ )
415 if ( base->in[ i ] != NULL )
416 mlt_service_close( base->in[ i ] );
417 this->parent.close = NULL;
420 mlt_properties_close( &this->parent );