-/*
- * mlt_consumer.h -- abstraction for all consumer services
- * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
- * Author: Charles Yates <charles.yates@pandora.be>
+/**
+ * \file mlt_consumer.h
+ * \brief abstraction for all consumer services
+ * \see mlt_consumer_s
+ *
+ * Copyright (C) 2003-2010 Ushodaya Enterprises Limited
+ * \author Charles Yates <charles.yates@pandora.be>
+ * \author Dan Dennedy <dan@dennedy.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
#include "mlt_events.h"
#include <pthread.h>
-/** The interface definition for all consumers.
-*/
+/** \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 prefill the number of frames to render before commencing
+ * output when real_time <> 0, defaults to the size of buffer
+ * \properties \em drop_max the maximum number of consecutively dropped frames, defaults to 5
+ * \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 fire this immediately after showing a frame
+ * or when a frame should be shown (if audio-only consumer).
+ * \event \em consumer-frame-render The base class fires this immediately before rendering a frame.
+ * \event \em consumer-thread-create Override the implementation of creating and
+ * starting a thread by listening and responding to this (real_time 1 or -1 only).
+ * \event \em consumer-thread-join Override the implementation of waiting and
+ * joining a terminated thread by listening and responding to this (real_time 1 or -1 only).
+ * \event \em consumer-thread-started The base class fires when beginning execution of a rendering thread.
+ * \event \em consumer-thread-stopped The base class fires when a rendering thread has ended.
+ * \event \em consumer-stopping This is fired when stop was requested, but before render threads are joined.
+ * \event \em consumer-stopped This is fired when the subclass implementation calls mlt_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
+ * \properties \em priority the OS scheduling priority for the render threads when real_time is not 0.
+ * \properties \em top_field_first when not progressive, whether interlace field order is top-field-first, defaults to 0.
+ * Set this to -1 if the consumer does not care about the field order.
+ * \properties \em mlt_image_format the image format to request in rendering threads, defaults to yuv422
+ * \properties \em mlt_audio_format the audio format to request in rendering threads, defaults to S16
+ */
struct mlt_consumer_s
{
- /* We're implementing service here */
+ /** A consumer is a service. */
struct mlt_service_s parent;
- /* public virtual */
+ /** 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 );
- void ( *close )( mlt_consumer );
- /* Private data */
- void *local;
- void *child;
+ /** Purge the consumer of buffered data (virtual function).
+ *
+ * \param mlt_consumer a consumer
+ */
+ void ( *purge )( mlt_consumer );
- 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;
-};
+ /** The destructor virtual function
+ *
+ * \param mlt_consumer a consumer
+ */
+ void ( *close )( mlt_consumer );
-/** Public final methods
-*/
+ void *local; /**< \private instance object */
+ void *child; /**< \private the object of a subclass */
+};
#define MLT_CONSUMER_SERVICE( consumer ) ( &( consumer )->parent )
#define MLT_CONSUMER_PROPERTIES( consumer ) MLT_SERVICE_PROPERTIES( MLT_CONSUMER_SERVICE( consumer ) )
extern int mlt_consumer_is_stopped( mlt_consumer self );
extern void mlt_consumer_stopped( mlt_consumer self );
extern void mlt_consumer_close( mlt_consumer );
+extern mlt_position mlt_consumer_position( mlt_consumer );
#endif