/** * \file mlt_consumer.h * \brief abstraction for all consumer services * \see mlt_consumer_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_CONSUMER_H_ #define _MLT_CONSUMER_H_ #include "mlt_service.h" #include "mlt_events.h" #include /** \brief Consumer abstract service class * * A consumer is a service that pulls audio and video from the connected * producers, filters, and transitions. Typically a consumer is used to * output audio and/or video to a device, file, or socket. * * \extends mlt_service_s * \properties \em rescale the scaling algorithm to pass on to all scaling * filters, defaults to "bilinear" * \properties \em buffer the number of frames to use in the asynchronous * render thread, defaults to 25 * \properties \em frequency the audio sample rate to use in Hertz, defaults to 48000 * \properties \em channels the number of audio channels to use, defaults to 2 * \properties \em real_time the asynchronous behavior: 1 (default) for asynchronous * with frame dropping, -1 for asynchronous without frame dropping, 0 to disable (synchronous) * \properties \em test_card the name of a resource to use as the test card, defaults to * environment variable MLT_TEST_CARD. If undefined, the hard-coded default test card is * white silence. A test card is what appears when nothing is produced. * \event \em consumer-frame-show Subclass implementations should fire this. * \event \em consumer-frame-render The abstract class fires this. * \event \em consumer-stopped * \properties \em fps video frames per second as floating point (read only) * \properties \em frame_rate_num the numerator of the video frame rate, overrides \p mlt_profile_s * \properties \em frame_rate_den the denominator of the video frame rate, overrides \p mlt_profile_s * \properties \em width the horizontal video resolution, overrides \p mlt_profile_s * \properties \em height the vertical video resolution, overrides \p mlt_profile_s * \properties \em progressive a flag that indicates if the video is interlaced * or progressive, overrides \p mlt_profile_s * \properties \em aspect_ratio the video sample (pixel) aspect ratio as floating point (read only) * \properties \em sample_aspect_num the numerator of the sample aspect ratio, overrides \p mlt_profile_s * \properties \em sample_aspect_den the denominator of the sample aspect ratio, overrides \p mlt_profile_s * \properties \em display_ratio the video frame aspect ratio as floating point (read only) * \properties \em display_aspect_num the numerator of the video frame aspect ratio, overrides \p mlt_profile_s * \properties \em display_aspect_den the denominator of the video frame aspect ratio, overrides \p mlt_profile_s * */ struct mlt_consumer_s { /** A consumer is a service. */ struct mlt_service_s parent; /** Start the consumer to pull frames (virtual function). * * \param mlt_consumer a consumer * \return true if there was an error */ int ( *start )( mlt_consumer ); /** Stop the consumer (virtual function). * * \param mlt_consumer a consumer * \return true if there was an error */ int ( *stop )( mlt_consumer ); /** Get whether the consumer is running or stopped (virtual function). * * \param mlt_consumer a consumer * \return true if the consumer is stopped */ int ( *is_stopped )( mlt_consumer ); /** The destructor virtual function * * \param mlt_consumer a consumer */ void ( *close )( mlt_consumer ); void *local; /**< \private instance object */ void *child; /**< \private the object of a subclass */ int real_time; int ahead; mlt_image_format format; mlt_deque queue; pthread_t ahead_thread; pthread_mutex_t mutex; pthread_cond_t cond; pthread_mutex_t put_mutex; pthread_cond_t put_cond; mlt_frame put; int put_active; mlt_event event_listener; }; #define MLT_CONSUMER_SERVICE( consumer ) ( &( consumer )->parent ) #define MLT_CONSUMER_PROPERTIES( consumer ) MLT_SERVICE_PROPERTIES( MLT_CONSUMER_SERVICE( consumer ) ) extern int mlt_consumer_init( mlt_consumer self, void *child, mlt_profile profile ); extern mlt_consumer mlt_consumer_new( mlt_profile profile ); extern mlt_service mlt_consumer_service( mlt_consumer self ); extern mlt_properties mlt_consumer_properties( mlt_consumer self ); extern int mlt_consumer_connect( mlt_consumer self, mlt_service producer ); extern int mlt_consumer_start( mlt_consumer self ); extern void mlt_consumer_purge( mlt_consumer self ); extern int mlt_consumer_put_frame( mlt_consumer self, mlt_frame frame ); extern mlt_frame mlt_consumer_get_frame( mlt_consumer self ); extern mlt_frame mlt_consumer_rt_frame( mlt_consumer self ); extern int mlt_consumer_stop( mlt_consumer self ); extern int mlt_consumer_is_stopped( mlt_consumer self ); extern void mlt_consumer_stopped( mlt_consumer self ); extern void mlt_consumer_close( mlt_consumer ); #endif