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/* -*- c-basic-offset: 2 -*-
*
* GStreamer
* Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu>
* 2006 Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>
*
* 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.
*
*
* this windowed sinc filter is taken from the freely downloadable DSP book,
* "The Scientist and Engineer's Guide to Digital Signal Processing",
* chapter 16
* available at http://www.dspguide.com/
*
*/
#ifndef __GST_AUDIO_WSINC_LIMIT_H__
#define __GST_AUDIO_WSINC_LIMIT_H__
#include <gst/gst.h>
#include <gst/audio/gstaudiofilter.h>
G_BEGIN_DECLS
#define GST_TYPE_AUDIO_WSINC_LIMIT \
(audio_wsinclimit_get_type())
#define GST_AUDIO_WSINC_LIMIT(obj) \
(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AUDIO_WSINC_LIMIT,GstAudioWSincLimit))
#define GST_AUDIO_WSINC_LIMIT_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AUDIO_WSINC_LIMIT,GstAudioWSincLimitClass))
#define GST_IS_AUDIO_WSINC_LIMIT(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AUDIO_WSINC_LIMIT))
#define GST_IS_AUDIO_WSINC_LIMIT_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AUDIO_WSINC_LIMIT))
typedef struct _GstAudioWSincLimit GstAudioWSincLimit;
typedef struct _GstAudioWSincLimitClass GstAudioWSincLimitClass;
typedef void (*GstAudioWSincLimitProcessFunc) (GstAudioWSincLimit *, guint8 *, guint8 *, guint);
/**
* GstAudioWSincLimit:
*
* Opaque data structure.
*/
struct _GstAudioWSincLimit {
GstAudioFilter element;
/* < private > */
GstAudioWSincLimitProcessFunc process;
gint mode;
gint window;
gfloat cutoff;
gint kernel_length; /* length of the filter kernel */
gdouble *residue; /* buffer for left-over samples from previous buffer */
gdouble *kernel; /* filter kernel */
gboolean have_kernel;
gint residue_length;
guint64 latency;
GstClockTime next_ts;
guint64 next_off;
};
struct _GstAudioWSincLimitClass {
GstAudioFilterClass parent_class;
};
GType audio_wsinclimit_get_type (void);
G_END_DECLS
#endif /* __GST_AUDIO_WSINC_LIMIT_H__ */
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