gst/audiofx/: Implement a base class for IIR filters.

Original commit message from CVS:
* gst/audiofx/Makefile.am:
* gst/audiofx/audiofxbaseiirfilter.c:
(gst_audio_fx_base_iir_filter_base_init),
(gst_audio_fx_base_iir_filter_dispose),
(gst_audio_fx_base_iir_filter_class_init),
(gst_audio_fx_base_iir_filter_init),
(gst_audio_fx_base_iir_filter_calculate_gain),
(gst_audio_fx_base_iir_filter_set_coefficients),
(gst_audio_fx_base_iir_filter_setup), (process),
(gst_audio_fx_base_iir_filter_transform_ip),
(gst_audio_fx_base_iir_filter_stop):
* gst/audiofx/audiofxbaseiirfilter.h:
Implement a base class for IIR filters.
* gst/audiofx/audiochebband.c: (gst_audio_cheb_band_base_init),
(gst_audio_cheb_band_class_init), (gst_audio_cheb_band_init),
(generate_coefficients), (gst_audio_cheb_band_set_property),
(gst_audio_cheb_band_setup):
* gst/audiofx/audiochebband.h:
* gst/audiofx/audiocheblimit.c: (gst_audio_cheb_limit_base_init),
(gst_audio_cheb_limit_class_init), (gst_audio_cheb_limit_init),
(generate_coefficients), (gst_audio_cheb_limit_set_property),
(gst_audio_cheb_limit_setup):
* gst/audiofx/audiocheblimit.h:
Use the IIR filter base class for the chebyshev filters.

1 files changed, 77 insertions, 0 deletions

diff --git a/gst/audiofx/audiofxbaseiirfilter.h b/gst/audiofx/audiofxbaseiirfilter.h
new file mode 100644
index 00000000..0534343c
--- /dev/null
+++ b/gst/audiofx/audiofxbaseiirfilter.h
@@ -0,0 +1,77 @@
+/* 
+ * GStreamer
+ * Copyright (C) 2007-2009 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __GST_AUDIO_FX_BASE_IIR_FILTER_H__
+#define __GST_AUDIO_FX_BASE_IIR_FILTER_H__
+
+#include <gst/gst.h>
+#include <gst/base/gstbasetransform.h>
+#include <gst/audio/audio.h>
+#include <gst/audio/gstaudiofilter.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_AUDIO_FX_BASE_IIR_FILTER            (gst_audio_fx_base_iir_filter_get_type())
+#define GST_AUDIO_FX_BASE_IIR_FILTER(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AUDIO_FX_BASE_IIR_FILTER,GstAudioFXBaseIIRFilter))
+#define GST_IS_AUDIO_FX_BASE_IIR_FILTER(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AUDIO_FX_BASE_IIR_FILTER))
+#define GST_AUDIO_FX_BASE_IIR_FILTER_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass) ,GST_TYPE_AUDIO_FX_BASE_IIR_FILTER,GstAudioFXBaseIIRFilterClass))
+#define GST_IS_AUDIO_FX_BASE_IIR_FILTER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass) ,GST_TYPE_AUDIO_FX_BASE_IIR_FILTER))
+#define GST_AUDIO_FX_BASE_IIR_FILTER_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS((obj) ,GST_TYPE_AUDIO_FX_BASE_IIR_FILTER,GstAudioFXBaseIIRFilterClass))
+typedef struct _GstAudioFXBaseIIRFilter GstAudioFXBaseIIRFilter;
+typedef struct _GstAudioFXBaseIIRFilterClass GstAudioFXBaseIIRFilterClass;
+
+typedef void (*GstAudioFXBaseIIRFilterProcessFunc) (GstAudioFXBaseIIRFilter *, guint8 *, guint);
+
+typedef struct
+{
+  gdouble *x;
+  gint x_pos;
+  gdouble *y;
+  gint y_pos;
+} GstAudioFXBaseIIRFilterChannelCtx;
+
+struct _GstAudioFXBaseIIRFilter
+{
+  GstAudioFilter audiofilter;
+
+  /* < private > */
+  GstAudioFXBaseIIRFilterProcessFunc process;
+
+  gboolean have_coeffs;
+  gdouble *a;
+  guint na;
+  gdouble *b;
+  guint nb;
+  GstAudioFXBaseIIRFilterChannelCtx *channels;
+  guint nchannels;
+};
+
+struct _GstAudioFXBaseIIRFilterClass
+{
+  GstAudioFilterClass parent;
+};
+
+GType gst_audio_fx_base_iir_filter_get_type (void);
+void gst_audio_fx_base_iir_filter_set_coefficients (GstAudioFXBaseIIRFilter *filter, gdouble *a, guint na, gdouble *b, guint nb);
+gdouble gst_audio_fx_base_iir_filter_calculate_gain (gdouble *a, guint na, gdouble *b, guint nb, gdouble zr, gdouble zi);
+
+G_END_DECLS
+
+#endif /* __GST_AUDIO_FX_BASE_IIR_FILTER_H__ */