gstreamer/gst-libs/gst/audio/streamvolume.h
2020-03-20 06:20:43 +00:00

80 lines
2.8 KiB
C

/* GStreamer StreamVolume
* Copyright (C) 2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_STREAM_VOLUME_H__
#define __GST_STREAM_VOLUME_H__
#include <gst/gst.h>
#include <gst/audio/audio-prelude.h>
G_BEGIN_DECLS
#define GST_TYPE_STREAM_VOLUME (gst_stream_volume_get_type ())
GST_AUDIO_API
G_DECLARE_INTERFACE (GstStreamVolume, gst_stream_volume, GST, STREAM_VOLUME,
GObject)
#define GST_STREAM_VOLUME_GET_INTERFACE(obj) GST_STREAM_VOLUME_GET_IFACE(obj)
struct _GstStreamVolumeInterface {
GTypeInterface iface;
};
/**
* GstStreamVolumeFormat:
* @GST_STREAM_VOLUME_FORMAT_LINEAR: Linear scale factor, 1.0 = 100%
* @GST_STREAM_VOLUME_FORMAT_CUBIC: Cubic volume scale
* @GST_STREAM_VOLUME_FORMAT_DB: Logarithmic volume scale (dB, amplitude not power)
*
* Different representations of a stream volume. gst_stream_volume_convert_volume()
* allows to convert between the different representations.
*
* Formulas to convert from a linear to a cubic or dB volume are
* cbrt(val) and 20 * log10 (val).
*/
typedef enum {
GST_STREAM_VOLUME_FORMAT_LINEAR = 0,
GST_STREAM_VOLUME_FORMAT_CUBIC,
GST_STREAM_VOLUME_FORMAT_DB
} GstStreamVolumeFormat;
GST_AUDIO_API
void gst_stream_volume_set_volume (GstStreamVolume *volume,
GstStreamVolumeFormat format,
gdouble val);
GST_AUDIO_API
gdouble gst_stream_volume_get_volume (GstStreamVolume *volume,
GstStreamVolumeFormat format);
GST_AUDIO_API
void gst_stream_volume_set_mute (GstStreamVolume *volume,
gboolean mute);
GST_AUDIO_API
gboolean gst_stream_volume_get_mute (GstStreamVolume *volume);
GST_AUDIO_API
gdouble gst_stream_volume_convert_volume (GstStreamVolumeFormat from,
GstStreamVolumeFormat to,
gdouble val) G_GNUC_CONST;
G_END_DECLS
#endif /* __GST_STREAM_VOLUME_H__ */