/** * \file mlt_service.c * \brief interface definition for all service classes * \see mlt_service_s * * Copyright (C) 2003-2009 Ushodaya Enterprises Limited * \author Charles Yates * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include "mlt_service.h" #include "mlt_filter.h" #include "mlt_frame.h" #include "mlt_cache.h" #include "mlt_factory.h" #include "mlt_log.h" #include #include #include #include /* IMPORTANT NOTES The base service implements a null frame producing service - as such, it is functional without extension and will produce test cards frames and PAL sized audio frames. PLEASE DO NOT CHANGE THIS BEHAVIOUR!!! OVERRIDE THE METHODS THAT CONTROL THIS IN EXTENDING CLASSES. */ /** \brief private service definition */ typedef struct { int size; int count; mlt_service *in; mlt_service out; int filter_count; int filter_size; mlt_filter *filters; pthread_mutex_t mutex; } mlt_service_base; /* Private methods */ static void mlt_service_disconnect( mlt_service this ); static void mlt_service_connect( mlt_service this, mlt_service that ); static int service_get_frame( mlt_service this, mlt_frame_ptr frame, int index ); static void mlt_service_property_changed( mlt_listener, mlt_properties owner, mlt_service this, void **args ); static void purge_cache( mlt_service self ); /** Initialize a service. * * \public \memberof mlt_service_s * \param this the service structure to initialize * \param child pointer to the child object for the subclass * \return true if there was an error */ int mlt_service_init( mlt_service this, void *child ) { int error = 0; // Initialise everything to NULL memset( this, 0, sizeof( struct mlt_service_s ) ); // Assign the child this->child = child; // Generate local space this->local = calloc( sizeof( mlt_service_base ), 1 ); // Associate the methods this->get_frame = service_get_frame; // Initialise the properties error = mlt_properties_init( &this->parent, this ); if ( error == 0 ) { this->parent.close = ( mlt_destructor )mlt_service_close; this->parent.close_object = this; mlt_events_init( &this->parent ); mlt_events_register( &this->parent, "service-changed", NULL ); mlt_events_register( &this->parent, "property-changed", ( mlt_transmitter )mlt_service_property_changed ); pthread_mutex_init( &( ( mlt_service_base * )this->local )->mutex, NULL ); } return error; } /** The transmitter for property changes. * * Invokes the listener. * * \private \memberof mlt_service_s * \param listener a function pointer that will be invoked * \param owner a properties list that will be passed to \p listener * \param this a service that will be passed to \p listener * \param args an array of pointers - the first entry is passed as a string to \p listener */ static void mlt_service_property_changed( mlt_listener listener, mlt_properties owner, mlt_service this, void **args ) { if ( listener != NULL ) listener( owner, this, ( char * )args[ 0 ] ); } /** Acquire a mutual exclusion lock on this service. * * \public \memberof mlt_service_s * \param this the service to lock */ void mlt_service_lock( mlt_service this ) { if ( this != NULL ) pthread_mutex_lock( &( ( mlt_service_base * )this->local )->mutex ); } /** Release a mutual exclusion lock on this service. * * \public \memberof mlt_service_s * \param this the service to unlock */ void mlt_service_unlock( mlt_service this ) { if ( this != NULL ) pthread_mutex_unlock( &( ( mlt_service_base * )this->local )->mutex ); } /** Identify the subclass of the service. * * \public \memberof mlt_service_s * \param this a service * \return the subclass */ mlt_service_type mlt_service_identify( mlt_service this ) { mlt_service_type type = invalid_type; if ( this != NULL ) { mlt_properties properties = MLT_SERVICE_PROPERTIES( this ); char *mlt_type = mlt_properties_get( properties, "mlt_type" ); char *resource = mlt_properties_get( properties, "resource" ); if ( mlt_type == NULL ) type = unknown_type; else if (resource != NULL && !strcmp( resource, "" ) ) type = playlist_type; else if (resource != NULL && !strcmp( resource, "" ) ) type = tractor_type; else if (resource != NULL && !strcmp( resource, "" ) ) type = multitrack_type; else if ( !strcmp( mlt_type, "producer" ) ) type = producer_type; else if ( !strcmp( mlt_type, "filter" ) ) type = filter_type; else if ( !strcmp( mlt_type, "transition" ) ) type = transition_type; else if ( !strcmp( mlt_type, "consumer" ) ) type = consumer_type; else type = unknown_type; } return type; } /** Connect a producer to the service. * * \public \memberof mlt_service_s * \param this a service * \param producer a producer * \param index which of potentially multiple producers to this service (0 based) * \return > 0 warning, == 0 success, < 0 serious error, * 1 = this service does not accept input, * 2 = the producer is invalid, * 3 = the producer is already registered with this consumer */ int mlt_service_connect_producer( mlt_service this, mlt_service producer, int index ) { int i = 0; // Get the service base mlt_service_base *base = this->local; // Special case 'track' index - only works for last filter(s) in a particular chain // but allows a filter to apply to the output frame regardless of which track it comes from if ( index == -1 ) index = 0; // Check if the producer is already registered with this service for ( i = 0; i < base->count; i ++ ) if ( base->in[ i ] == producer ) return 3; // Allocate space if ( index >= base->size ) { int new_size = base->size + index + 10; base->in = realloc( base->in, new_size * sizeof( mlt_service ) ); if ( base->in != NULL ) { for ( i = base->size; i < new_size; i ++ ) base->in[ i ] = NULL; base->size = new_size; } } // If we have space, assign the input if ( base->in != NULL && index >= 0 && index < base->size ) { // Get the current service mlt_service current = base->in[ index ]; // Increment the reference count on this producer if ( producer != NULL ) mlt_properties_inc_ref( MLT_SERVICE_PROPERTIES( producer ) ); // Now we disconnect the producer service from its consumer mlt_service_disconnect( producer ); // Add the service to index specified base->in[ index ] = producer; // Determine the number of active tracks if ( index >= base->count ) base->count = index + 1; // Now we connect the producer to its connected consumer mlt_service_connect( producer, this ); // Close the current service mlt_service_close( current ); // Inform caller that all went well return 0; } else { return -1; } } /** Disconnect this service from its consumer. * * \public \memberof mlt_service_s * \param this a service */ static void mlt_service_disconnect( mlt_service this ) { if ( this != NULL ) { // Get the service base mlt_service_base *base = this->local; // Disconnect base->out = NULL; } } /** Obtain the consumer this service is connected to. * * \public \memberof mlt_service_s * \param this a service * \return the consumer */ mlt_service mlt_service_consumer( mlt_service this ) { // Get the service base mlt_service_base *base = this->local; // Return the connected consumer return base->out; } /** Obtain the producer this service is connected to. * * \public \memberof mlt_service_s * \param this a service * \return the last-most producer */ mlt_service mlt_service_producer( mlt_service this ) { // Get the service base mlt_service_base *base = this->local; // Return the connected producer return base->count > 0 ? base->in[ base->count - 1 ] : NULL; } /** Associate this service to a consumer. * * Overwrites connection to any existing consumer. * \private \memberof mlt_service_s * \param this a service * \param that a consumer */ static void mlt_service_connect( mlt_service this, mlt_service that ) { if ( this != NULL ) { // Get the service base mlt_service_base *base = this->local; // There's a bit more required here... base->out = that; } } /** Get the first connected producer. * * \public \memberof mlt_service_s * \param this a service * \return the first producer */ mlt_service mlt_service_get_producer( mlt_service this ) { mlt_service producer = NULL; // Get the service base mlt_service_base *base = this->local; if ( base->in != NULL ) producer = base->in[ 0 ]; return producer; } /** Default implementation of the get_frame virtual function. * * \private \memberof mlt_service_s * \param this a service * \param[out] frame a frame by reference * \param index as determined by the producer * \return false */ static int service_get_frame( mlt_service this, mlt_frame_ptr frame, int index ) { mlt_service_base *base = this->local; if ( index < base->count ) { mlt_service producer = base->in[ index ]; if ( producer != NULL ) return mlt_service_get_frame( producer, frame, index ); } *frame = mlt_frame_init( this ); return 0; } /** Return the properties object. * * \public \memberof mlt_service_s * \param this a service * \return the properties */ mlt_properties mlt_service_properties( mlt_service this ) { return this != NULL ? &this->parent : NULL; } /** Recursively apply attached filters. * * \public \memberof mlt_service_s * \param this a service * \param frame a frame * \param index used to track depth of recursion, top caller should supply 0 */ void mlt_service_apply_filters( mlt_service this, mlt_frame frame, int index ) { int i; mlt_properties frame_properties = MLT_FRAME_PROPERTIES( frame ); mlt_properties service_properties = MLT_SERVICE_PROPERTIES( this ); mlt_service_base *base = this->local; mlt_position position = mlt_frame_get_position( frame ); mlt_position this_in = mlt_properties_get_position( service_properties, "in" ); mlt_position this_out = mlt_properties_get_position( service_properties, "out" ); if ( index == 0 || mlt_properties_get_int( service_properties, "_filter_private" ) == 0 ) { // Process the frame with the attached filters for ( i = 0; i < base->filter_count; i ++ ) { if ( base->filters[ i ] != NULL ) { mlt_position in = mlt_filter_get_in( base->filters[ i ] ); mlt_position out = mlt_filter_get_out( base->filters[ i ] ); int disable = mlt_properties_get_int( MLT_FILTER_PROPERTIES( base->filters[ i ] ), "disable" ); if ( !disable && ( ( in == 0 && out == 0 ) || ( position >= in && ( position <= out || out == 0 ) ) ) ) { mlt_properties_set_position( frame_properties, "in", in == 0 ? this_in : in ); mlt_properties_set_position( frame_properties, "out", out == 0 ? this_out : out ); mlt_filter_process( base->filters[ i ], frame ); mlt_service_apply_filters( MLT_FILTER_SERVICE( base->filters[ i ] ), frame, index + 1 ); } } } } } /** Obtain a frame. * * \public \memberof mlt_service_s * \param this a service * \param[out] frame a frame by reference * \param index as determined by the producer * \return true if there was an error */ int mlt_service_get_frame( mlt_service this, mlt_frame_ptr frame, int index ) { int result = 0; // Lock the service mlt_service_lock( this ); // Ensure that the frame is NULL *frame = NULL; // Only process if we have a valid service if ( this != NULL && this->get_frame != NULL ) { mlt_properties properties = MLT_SERVICE_PROPERTIES( this ); mlt_position in = mlt_properties_get_position( properties, "in" ); mlt_position out = mlt_properties_get_position( properties, "out" ); result = this->get_frame( this, frame, index ); if ( result == 0 ) { mlt_properties_inc_ref( properties ); properties = MLT_FRAME_PROPERTIES( *frame ); if ( in >=0 && out > 0 ) { mlt_properties_set_position( properties, "in", in ); mlt_properties_set_position( properties, "out", out ); } mlt_service_apply_filters( this, *frame, 1 ); mlt_deque_push_back( MLT_FRAME_SERVICE_STACK( *frame ), this ); } } // Make sure we return a frame if ( *frame == NULL ) *frame = mlt_frame_init( this ); // Unlock the service mlt_service_unlock( this ); return result; } /** The service-changed event handler. * * \private \memberof mlt_service_s * \param owner ignored * \param this the service on which the "service-changed" event is fired */ static void mlt_service_filter_changed( mlt_service owner, mlt_service this ) { mlt_events_fire( MLT_SERVICE_PROPERTIES( this ), "service-changed", NULL ); } /** Attach a filter. * * \public \memberof mlt_service_s * \param this a service * \param filter the filter to attach * \return true if there was an error */ int mlt_service_attach( mlt_service this, mlt_filter filter ) { int error = this == NULL || filter == NULL; if ( error == 0 ) { int i = 0; mlt_properties properties = MLT_SERVICE_PROPERTIES( this ); mlt_service_base *base = this->local; for ( i = 0; error == 0 && i < base->filter_count; i ++ ) if ( base->filters[ i ] == filter ) error = 1; if ( error == 0 ) { if ( base->filter_count == base->filter_size ) { base->filter_size += 10; base->filters = realloc( base->filters, base->filter_size * sizeof( mlt_filter ) ); } if ( base->filters != NULL ) { mlt_properties props = MLT_FILTER_PROPERTIES( filter ); mlt_properties_inc_ref( MLT_FILTER_PROPERTIES( filter ) ); base->filters[ base->filter_count ++ ] = filter; mlt_events_fire( properties, "service-changed", NULL ); mlt_events_listen( props, this, "service-changed", ( mlt_listener )mlt_service_filter_changed ); mlt_events_listen( props, this, "property-changed", ( mlt_listener )mlt_service_filter_changed ); } else { error = 2; } } } return error; } /** Detach a filter. * * \public \memberof mlt_service_s * \param this a service * \param filter the filter to detach * \return true if there was an error */ int mlt_service_detach( mlt_service this, mlt_filter filter ) { int error = this == NULL || filter == NULL; if ( error == 0 ) { int i = 0; mlt_service_base *base = this->local; mlt_properties properties = MLT_SERVICE_PROPERTIES( this ); for ( i = 0; i < base->filter_count; i ++ ) if ( base->filters[ i ] == filter ) break; if ( i < base->filter_count ) { base->filters[ i ] = NULL; for ( i ++ ; i < base->filter_count; i ++ ) base->filters[ i - 1 ] = base->filters[ i ]; base->filter_count --; mlt_events_disconnect( MLT_FILTER_PROPERTIES( filter ), this ); mlt_filter_close( filter ); mlt_events_fire( properties, "service-changed", NULL ); } } return error; } /** Retrieve a filter. * * \public \memberof mlt_service_s * \param this a service * \param index which one of potentially multiple filters * \return the filter or null if there was an error */ mlt_filter mlt_service_filter( mlt_service this, int index ) { mlt_filter filter = NULL; if ( this != NULL ) { mlt_service_base *base = this->local; if ( index >= 0 && index < base->filter_count ) filter = base->filters[ index ]; } return filter; } /** Retrieve the profile. * * \public \memberof mlt_service_s * \param this a service * \return the profile */ mlt_profile mlt_service_profile( mlt_service this ) { return mlt_properties_get_data( MLT_SERVICE_PROPERTIES( this ), "_profile", NULL ); } /** Destroy a service. * * \public \memberof mlt_service_s * \param this the service to destroy */ void mlt_service_close( mlt_service this ) { if ( this != NULL && mlt_properties_dec_ref( MLT_SERVICE_PROPERTIES( this ) ) <= 0 ) { if ( this->close != NULL ) { this->close( this->close_object ); } else { mlt_service_base *base = this->local; int i = 0; int count = base->filter_count; mlt_events_block( MLT_SERVICE_PROPERTIES( this ), this ); while( count -- ) mlt_service_detach( this, base->filters[ 0 ] ); free( base->filters ); for ( i = 0; i < base->count; i ++ ) if ( base->in[ i ] != NULL ) mlt_service_close( base->in[ i ] ); this->parent.close = NULL; free( base->in ); pthread_mutex_destroy( &base->mutex ); free( base ); purge_cache( this ); mlt_properties_close( &this->parent ); } } else { mlt_service_unlock( this ); } } /** Release a service's cache items. * * \private \memberof mlt_service_s * \param self a service */ static void purge_cache( mlt_service self ) { mlt_properties caches = mlt_properties_get_data( mlt_global_properties(), "caches", NULL ); if ( caches ) { int i = mlt_properties_count( caches ); while ( i-- ) { mlt_cache_purge( mlt_properties_get_data_at( caches, i, NULL ), self ); mlt_properties_set_data( mlt_global_properties(), mlt_properties_get_name( caches, i ), NULL, 0, NULL, NULL ); } } } /** Lookup the cache object for a service. * * \private \memberof mlt_service_s * \param self a service * \param name a name for the object * \return a cache */ static mlt_cache get_cache( mlt_service self, const char *name ) { mlt_cache result = NULL; mlt_properties caches = mlt_properties_get_data( mlt_global_properties(), "caches", NULL ); if ( !caches ) { caches = mlt_properties_new(); mlt_properties_set_data( mlt_global_properties(), "caches", caches, 0, ( mlt_destructor )mlt_properties_close, NULL ); } if ( caches ) { result = mlt_properties_get_data( caches, name, NULL ); if ( !result ) { result = mlt_cache_init(); mlt_properties_set_data( caches, name, result, 0, ( mlt_destructor )mlt_cache_close, NULL ); } } return result; } /** Put an object into a service's cache. * * \public \memberof mlt_service_s * \param self a service * \param name a name for the object that is unique to the service class, but not to the instance * \param data an opaque pointer to the object to put into the cache * \param size the number of bytes pointed to by data * \param destructor a function that releases the data */ void mlt_service_cache_put( mlt_service self, const char *name, void* data, int size, mlt_destructor destructor ) { mlt_log( self, MLT_LOG_DEBUG, "%s: name %s object %p data %p\n", __FUNCTION__, name, self, data ); mlt_cache cache = get_cache( self, name ); if ( cache ) mlt_cache_put( cache, self, data, size, destructor ); } /** Get an object from a service's cache. * * \public \memberof mlt_service_s * \param self a service * \param name a name for the object that is unique to the service class, but not to the instance * \return a cache item or NULL if an object is not found * \see mlt_cache_item_data */ mlt_cache_item mlt_service_cache_get( mlt_service self, const char *name ) { mlt_log( self, MLT_LOG_DEBUG, "%s: name %s object %p\n", __FUNCTION__, name, self ); mlt_cache_item result = NULL; mlt_cache cache = get_cache( self, name ); if ( cache ) result = mlt_cache_get( cache, self ); return result; }