/* GStreamer * * Copyright (C) 2007 Sebastian Dröge <slomo@circular-chaos.org> * * gstcontrolsource.h: Interface declaration for control sources * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library 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 __GST_CONTROL_SOURCE_H__ #define __GST_CONTROL_SOURCE_H__ #include <gst/gstconfig.h> #include <glib-object.h> #include <gst/gstclock.h> G_BEGIN_DECLS #define GST_TYPE_CONTROL_SOURCE \ (gst_control_source_get_type()) #define GST_CONTROL_SOURCE(obj) \ (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_CONTROL_SOURCE,GstControlSource)) #define GST_CONTROL_SOURCE_CLASS(klass) \ (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_CONTROL_SOURCE,GstControlSourceClass)) #define GST_IS_CONTROL_SOURCE(obj) \ (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_CONTROL_SOURCE)) #define GST_IS_CONTROL_SOURCE_CLASS(klass) \ (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_CONTROL_SOURCE)) #define GST_CONTROL_SOURCE_GET_CLASS(obj) \ (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_CONTOL_SOURCE, GstControlSourceClass)) typedef struct _GstControlSource GstControlSource; typedef struct _GstControlSourceClass GstControlSourceClass; typedef struct _GstTimedValue GstTimedValue; typedef struct _GstValueArray GstValueArray; /** * GstTimedValue: * @timestamp: timestamp of the value change * @value: the corresponding value * * Structure for saving a timestamp and a value. */ struct _GstTimedValue { GstClockTime timestamp; gdouble value; }; /** * GstControlSourceGetValue * @self: the #GstControlSource instance * @timestamp: timestamp for which a value should be calculated * @value: a #GValue which will be set to the result. It must be initialized to the correct type. * * Function for returning a value for a given timestamp. * * Returns: %TRUE if the value was successfully calculated. * */ typedef gboolean (* GstControlSourceGetValue) (GstControlSource *self, GstClockTime timestamp, gdouble *value); /** * GstControlSourceGetValueArray * @self: the #GstControlSource instance * @timestamp: timestamp for which a value should be calculated * @interval: the time spacing between subsequent values * @n_values: the number of values * @values: array to put control-values in * * Function for returning an array of values for starting at a given timestamp. * * Returns: %TRUE if the values were successfully calculated. * */ typedef gboolean (* GstControlSourceGetValueArray) (GstControlSource *self, GstClockTime timestamp, GstClockTime interval, guint n_values, gdouble *values); /** * GstControlSource: * @get_value: Function for returning a value for a given timestamp * @get_value_array: Function for returning a #GstValueArray for a given timestamp * * The instance structure of #GstControlSource. */ struct _GstControlSource { GstObject parent; /*< public >*/ GstControlSourceGetValue get_value; /* Returns the value for a property at a given timestamp */ GstControlSourceGetValueArray get_value_array; /* Returns values for a property in a given timespan */ /*< private >*/ gpointer _gst_reserved[GST_PADDING]; }; /** * GstControlSourceClass: * @parent_class: Parent class * @bind: Class method for binding the #GstControlSource to a specific GParamSpec * * The class structure of #GstControlSource. */ struct _GstControlSourceClass { GstObjectClass parent_class; /*< private >*/ gpointer _gst_reserved[GST_PADDING]; }; GType gst_control_source_get_type (void); /* Functions */ gboolean gst_control_source_get_value (GstControlSource *self, GstClockTime timestamp, gdouble *value); gboolean gst_control_source_get_value_array (GstControlSource *self, GstClockTime timestamp, GstClockTime interval, guint n_values, gdouble *values); G_END_DECLS #endif /* __GST_CONTROL_SOURCE_H__ */