gstreamer/libs/gst/control/unitconvert.h

/* GStreamer
 * Copyright (C) 2001 Steve Baker <stevebaker_org@yahoo.co.uk>
 *
 * unitconvert.c: Conversion between units of measurement
 *
 * 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_UNITCONVERT_H__
#define __GST_UNITCONVERT_H__

#include <gst/gstobject.h>

G_BEGIN_DECLS

#define GST_TYPE_UNIT_CONVERT			(gst_unitconv_get_type ())
#define GST_UNIT_CONVERT(obj)			(G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_UNIT_CONVERT,GstUnitConvert))
#define GST_UNIT_CONVERT_CLASS(klass)		(G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_UNIT_CONVERT,GstUnitConvert))
#define GST_IS_UNIT_CONVERT(obj)			(G_TYPE_CHECK_INSTANCE_TYPE	((obj), GST_TYPE_UNIT_CONVERT))
#define GST_IS_UNIT_CONVERT_CLASS(obj)		(G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_UNIT_CONVERT))

#define GST_UNIT_CONVERT_NAME(unitconv)				(GST_OBJECT_NAME(unitconv))
#define GST_UNIT_CONVERT_PARENT(unitconv)			(GST_OBJECT_PARENT(unitconv))

typedef struct _GstUnitConvertClass GstUnitConvertClass;
typedef struct _GstUnitConvert GstUnitConvert;

typedef void (*GstUnitConvertFunc) (GstUnitConvert *unitconv, GValue *from_val, GValue *to_val);

struct _GstUnitConvert {
	GstObject		object;

	GHashTable *convert_params;
	GSList *convert_func_chain;
	GSList *temp_gvalues;
};

struct _GstUnitConvertClass {
	GstObjectClass parent_class;

	/* signal callbacks */
};

GstUnitConvert* gst_unitconv_new (void);
void _gst_unitconv_initialize (void);

gboolean gst_unitconv_set_convert_units(GstUnitConvert *unitconv, gchar *from_unit_named, gchar *to_unit_named);
gboolean gst_unitconv_convert_value(GstUnitConvert *unitconv, GValue *from_value, GValue *to_value);

GParamSpec* gst_unitconv_unit_spec(gchar *unit_name);
gboolean gst_unitconv_unit_exists(gchar *unit_name);
gboolean gst_unitconv_unit_is_logarithmic(gchar *unit_name);

gboolean gst_unitconv_register_unit(const gchar *domain_name, 
                                    gboolean is_domain_default, 
                                    gboolean is_logarithmic,
                                    GParamSpec *unit_spec);

gboolean gst_unitconv_register_convert_func(gchar *from_unit_named, gchar *to_unit_named, GstUnitConvertFunc convert_func);
gboolean gst_unitconv_register_convert_property(gchar *unit_name, GParamSpec *convert_prop_spec);

G_END_DECLS

#endif /* __GST_UNITCONVERT_H__ */