/* 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 <glib-object.h>

#include <gst/gst.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;

  GValue value;

};

/**

 * GstValueArray:

 * @property_name: the name of the property this array belongs to

 * @nbsamples: number of samples requested

 * @sample_interval: interval between each sample

 * @values: pointer to the array

 *

 * Structure to receive multiple values at once.

 */

struct _GstValueArray

{

  gchar *property_name;

  gint nbsamples;

  GstClockTime sample_interval;

  gpointer *values;

};

/** 

 * 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, GValue *value);

/** 

 * GstControlSourceGetValueArray

 * @self: the #GstControlSource instance

 * @timestamp: timestamp for which a value should be calculated

 * @value_array: array to put control-values in

 *

 * Function for returning a #GstValueArray for a given timestamp.

 *

 * Returns: %TRUE if the values were successfully calculated.

 *

 */

typedef gboolean (* GstControlSourceGetValueArray) (GstControlSource *self, GstClockTime timestamp, GstValueArray *value_array);

/** 

 * GstControlSourceBind

 * @self: the #GstControlSource instance

 * @pspec: #GParamSpec that should be bound to

 *

 * Function for binding a #GstControlSource to a #GParamSpec.

 *

 * Returns: %TRUE if the property could be bound to the #GstControlSource, %FALSE otherwise.

 */

typedef gboolean (* GstControlSourceBind) (GstControlSource *self, GParamSpec *pspec);

/**

 * 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 {

  GObject 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 >*/

  gboolean bound;

  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

{

  GObjectClass parent_class;

  GstControlSourceBind bind;  /* Binds the GstControlSource to a specific GParamSpec */

  /*< private >*/

  gpointer _gst_reserved[GST_PADDING];

};

#ifdef __SYMBIAN32__

IMPORT_C

#endif

GType gst_control_source_get_type (void);

/* Functions */

#ifdef __SYMBIAN32__

IMPORT_C

#endif

gboolean gst_control_source_get_value (GstControlSource *self, GstClockTime timestamp, GValue *value);

#ifdef __SYMBIAN32__

IMPORT_C

#endif

gboolean gst_control_source_get_value_array (GstControlSource *self, GstClockTime timestamp, GstValueArray *value_array);

#ifdef __SYMBIAN32__

IMPORT_C

#endif

gboolean gst_control_source_bind (GstControlSource *self, GParamSpec *pspec);

G_END_DECLS

#endif /* __GST_CONTROL_SOURCE_H__ */