/** * \file mlt_producer.h * \brief abstraction for all producer services * \see mlt_producer_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 */ #ifndef _MLT_PRODUCER_H_ #define _MLT_PRODUCER_H_ #include "mlt_service.h" #include "mlt_filter.h" /** \brief Producer abstract service class * * A producer is a service that generates audio, video, and metadata. * Some day it may also generate text (subtitles). This is not to say * a producer "synthesizes," rather that is an origin of data within the * service network - that could be through synthesis or reading a stream. * * \extends mlt_service * \event \em producer-changed * \properties \em mlt_type the name of the service subclass, e.g. mlt_producer * \properties \em mlt_service the name of a producer subclass * \properties \em _position the current position of the play head, relative to the in point * \properties \em _frame the current position of the play head, relative to the beginning of the resource * \properties \em _speed the current speed factor, where 1.0 is normal * \properties \em aspect_ratio sample aspect ratio * \properties \em length the duration of the cut in frames * \properties \em eof the end-of-file behavior, one of: pause, continue, loop * \properties \em resource the file name, stream address, or the class name in angle brackets * \properties \em _cut set if this producer is a "cut" producer * \properties \em mlt_mix stores the data for a "mix" producer * \properties \em _cut_parent holds a reference to the cut's parent producer * \properties \em ignore_points Set this to temporarily disable the in and out points. * \properties \em use_clone holds a reference to a clone's producer, as created by mlt_producer_optimise * \properties \em _clone is the index of the clone in the list of clones stored on the clone's producer * \properties \em _clones is the number of clones of the producer, as created by mlt_producer_optimise * \properties \em _clone.{N} holds a reference to the N'th clone of the producer, as created by mlt_producer_optimise * \properties \em meta.* holds metadata - there is a loose taxonomy to be defined * \properties \em set.* holds properties to set on a frame produced * \todo define the media metadata taxonomy */ struct mlt_producer_s { /** A producer is a service. */ struct mlt_service_s parent; /** Get a frame of data (virtual function). * * \param mlt_producer a producer * \param mlt_frame_ptr a frame pointer by reference * \param int an index * \return true if there was an error */ int ( *get_frame )( mlt_producer, mlt_frame_ptr, int ); /** the destructor virtual function */ mlt_destructor close; void *close_object; /**< the object supplied to the close virtual function */ void *local; /**< \private instance object */ void *child; /**< \private the object of a subclass */ }; /* * Public final methods */ #define MLT_PRODUCER_SERVICE( producer ) ( &( producer )->parent ) #define MLT_PRODUCER_PROPERTIES( producer ) MLT_SERVICE_PROPERTIES( MLT_PRODUCER_SERVICE( producer ) ) extern int mlt_producer_init( mlt_producer self, void *child ); extern mlt_producer mlt_producer_new( ); extern mlt_service mlt_producer_service( mlt_producer self ); extern mlt_properties mlt_producer_properties( mlt_producer self ); extern int mlt_producer_seek( mlt_producer self, mlt_position position ); extern mlt_position mlt_producer_position( mlt_producer self ); extern mlt_position mlt_producer_frame( mlt_producer self ); extern int mlt_producer_set_speed( mlt_producer self, double speed ); extern double mlt_producer_get_speed( mlt_producer self ); extern double mlt_producer_get_fps( mlt_producer self ); extern int mlt_producer_set_in_and_out( mlt_producer self, mlt_position in, mlt_position out ); extern int mlt_producer_clear( mlt_producer self ); extern mlt_position mlt_producer_get_in( mlt_producer self ); extern mlt_position mlt_producer_get_out( mlt_producer self ); extern mlt_position mlt_producer_get_playtime( mlt_producer self ); extern mlt_position mlt_producer_get_length( mlt_producer self ); extern void mlt_producer_prepare_next( mlt_producer self ); extern int mlt_producer_attach( mlt_producer self, mlt_filter filter ); extern int mlt_producer_detach( mlt_producer self, mlt_filter filter ); extern mlt_filter mlt_producer_filter( mlt_producer self, int index ); extern mlt_producer mlt_producer_cut( mlt_producer self, int in, int out ); extern int mlt_producer_is_cut( mlt_producer self ); extern int mlt_producer_is_mix( mlt_producer self ); extern int mlt_producer_is_blank( mlt_producer self ); extern mlt_producer mlt_producer_cut_parent( mlt_producer self ); extern int mlt_producer_optimise( mlt_producer self ); extern void mlt_producer_close( mlt_producer self ); #endif