1 /* 

     2  * GStreamer

     3  * Copyright (C) 2007-2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>

     4  *

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

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

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

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

     9  *

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

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

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

    13  * Library General Public License for more details.

    14  *

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

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

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

    18  * Boston, MA 02111-1307, USA.

    19  */

    20 

    21 #ifndef __GST_AUDIO_FX_BASE_IIR_FILTER_H__

    22 #define __GST_AUDIO_FX_BASE_IIR_FILTER_H__

    23 

    24 #include <gst/gst.h>

    25 #include <gst/gst_global.h>

    26 #include <gst/base/gstbasetransform.h>

    27 #include <gst/audio/audio.h>

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

    29 

    30 G_BEGIN_DECLS

    31 

    32 #define GST_TYPE_AUDIO_FX_BASE_IIR_FILTER            (gst_audio_fx_base_iir_filter_get_type())

    33 #define GST_AUDIO_FX_BASE_IIR_FILTER(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AUDIO_FX_BASE_IIR_FILTER,GstAudioFXBaseIIRFilter))

    34 #define GST_IS_AUDIO_FX_BASE_IIR_FILTER(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AUDIO_FX_BASE_IIR_FILTER))

    35 #define GST_AUDIO_FX_BASE_IIR_FILTER_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass) ,GST_TYPE_AUDIO_FX_BASE_IIR_FILTER,GstAudioFXBaseIIRFilterClass))

    36 #define GST_IS_AUDIO_FX_BASE_IIR_FILTER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass) ,GST_TYPE_AUDIO_FX_BASE_IIR_FILTER))

    37 #define GST_AUDIO_FX_BASE_IIR_FILTER_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS((obj) ,GST_TYPE_AUDIO_FX_BASE_IIR_FILTER,GstAudioFXBaseIIRFilterClass))

    38 typedef struct _GstAudioFXBaseIIRFilter GstAudioFXBaseIIRFilter;

    39 typedef struct _GstAudioFXBaseIIRFilterClass GstAudioFXBaseIIRFilterClass;

    40 

    41 typedef void (*GstAudioFXBaseIIRFilterProcessFunc) (GstAudioFXBaseIIRFilter *, guint8 *, guint);

    42 

    43 typedef struct

    44 {

    45   gdouble *x;

    46   gint x_pos;

    47   gdouble *y;

    48   gint y_pos;

    49 } GstAudioFXBaseIIRFilterChannelCtx;

    50 

    51 struct _GstAudioFXBaseIIRFilter

    52 {

    53   GstAudioFilter audiofilter;

    54 

    55   /* < private > */

    56   GstAudioFXBaseIIRFilterProcessFunc process;

    57 

    58   gboolean have_coeffs;

    59   gdouble *a;

    60   guint na;

    61   gdouble *b;

    62   guint nb;

    63   GstAudioFXBaseIIRFilterChannelCtx *channels;

    64   guint nchannels;

    65 };

    66 

    67 struct _GstAudioFXBaseIIRFilterClass

    68 {

    69   GstAudioFilterClass parent;

    70 };

    71 #ifdef __SYMBIAN32__

    72 IMPORT_C

    73 #endif

    74 

    75 

    76 GType gst_audio_fx_base_iir_filter_get_type (void);

    77 void gst_audio_fx_base_iir_filter_set_coefficients (GstAudioFXBaseIIRFilter *filter, gdouble *a, guint na, gdouble *b, guint nb);

    78 gdouble gst_audio_fx_base_iir_filter_calculate_gain (gdouble *a, guint na, gdouble *b, guint nb, gdouble zr, gdouble zi);

    79 

    80 G_END_DECLS

    81 

    82 #endif /* __GST_AUDIO_FX_BASE_IIR_FILTER_H__ */