1 /* -*- c-basic-offset: 2 -*-

     2  * 

     3  * GStreamer

     4  * Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu>

     5  *               2006 Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>

     6  *               2007-2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>

     7  *

     8  * This library is free software; you can redistribute it and/or

     9  * modify it under the terms of the GNU Library General Public

    10  * License as published by the Free Software Foundation; either

    11  * version 2 of the License, or (at your option) any later version.

    12  *

    13  * This library is distributed in the hope that it will be useful,

    14  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    16  * Library General Public License for more details.

    17  *

    18  * You should have received a copy of the GNU Library General Public

    19  * License along with this library; if not, write to the

    20  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

    21  * Boston, MA 02111-1307, USA.

    22  * 

    23  * 

    24  * this windowed sinc filter is taken from the freely downloadable DSP book,

    25  * "The Scientist and Engineer's Guide to Digital Signal Processing",

    26  * chapter 16

    27  * available at http://www.dspguide.com/

    28  *

    29  */

    30 

    31 #ifndef __GST_AUDIO_WSINC_LIMIT_H__

    32 #define __GST_AUDIO_WSINC_LIMIT_H__

    33 

    34 #include <gst/gst.h>

    35 #include <gst/audio/gstaudiofilter.h>

    36 #include <gst/gst_global.h>

    37 

    38 #include "audiofxbasefirfilter.h"

    39 

    40 G_BEGIN_DECLS

    41 

    42 #define GST_TYPE_AUDIO_WSINC_LIMIT \

    43   (gst_audio_wsinclimit_get_type())

    44 #define GST_AUDIO_WSINC_LIMIT(obj) \

    45   (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AUDIO_WSINC_LIMIT,GstAudioWSincLimit))

    46 #define GST_AUDIO_WSINC_LIMIT_CLASS(klass) \

    47   (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AUDIO_WSINC_LIMIT,GstAudioWSincLimitClass))

    48 #define GST_IS_AUDIO_WSINC_LIMIT(obj) \

    49   (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AUDIO_WSINC_LIMIT))

    50 #define GST_IS_AUDIO_WSINC_LIMIT_CLASS(klass) \

    51   (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AUDIO_WSINC_LIMIT))

    52 

    53 typedef struct _GstAudioWSincLimit GstAudioWSincLimit;

    54 typedef struct _GstAudioWSincLimitClass GstAudioWSincLimitClass;

    55 

    56 /**

    57  * GstAudioWSincLimit:

    58  *

    59  * Opaque data structure.

    60  */

    61 struct _GstAudioWSincLimit {

    62   GstAudioFXBaseFIRFilter parent;

    63 

    64   gint mode;

    65   gint window;

    66   gfloat cutoff;

    67   gint kernel_length;

    68 

    69   /* < private > */

    70   GMutex *lock;

    71 };

    72 

    73 struct _GstAudioWSincLimitClass {

    74   GstAudioFXBaseFIRFilterClass parent;

    75 };

    76 #ifdef __SYMBIAN32__

    77 IMPORT_C

    78 #endif

    79 

    80 

    81 GType gst_audio_wsinclimit_get_type (void);

    82 

    83 G_END_DECLS

    84 

    85 #endif /* __GST_AUDIO_WSINC_LIMIT_H__ */