1 files changed, 77 insertions, 0 deletions
diff --git a/gst/equalizer/gstiirequalizer.h b/gst/equalizer/gstiirequalizer.h
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+++ b/gst/equalizer/gstiirequalizer.h
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+/* GStreamer IIR equalizer
+ * Copyright (C) <2004> Benjamin Otte <otte@gnome.org>
+ *
+ * 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_IIR_EQUALIZER__
+#define __GST_IIR_EQUALIZER__
+
+#include <gst/audio/gstaudiofilter.h>
+#include <gst/audio/gstringbuffer.h>
+
+typedef struct _GstIirEqualizer GstIirEqualizer;
+typedef struct _GstIirEqualizerClass GstIirEqualizerClass;
+
+#define GST_TYPE_IIR_EQUALIZER \
+  (gst_iir_equalizer_get_type())
+#define GST_IIR_EQUALIZER(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_IIR_EQUALIZER,GstIirEqualizer))
+#define GST_IIR_EQUALIZER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_IIR_EQUALIZER,GstIirEqualizerClass))
+#define GST_IS_IIR_EQUALIZER(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_IIR_EQUALIZER))
+#define GST_IS_IIR_EQUALIZER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_IIR_EQUALIZER))
+
+#define LOWEST_FREQ (20.0)
+#define HIGHEST_FREQ (20000.0)
+
+typedef void (*ProcessFunc) (GstIirEqualizer * eq, guint8 * data, guint size,
+    guint channels);
+
+typedef struct
+{
+  gdouble alpha;                /* IIR coefficients for outputs */
+  gdouble beta;                 /* IIR coefficients for inputs */
+  gdouble gamma;                /* IIR coefficients for inputs */
+} SecondOrderFilter;
+
+struct _GstIirEqualizer
+{
+  GstAudioFilter audiofilter;
+
+  /*< private >*/
+
+  /* properties */
+  guint freq_count;
+  gdouble band_width;
+  gdouble *freqs;
+  gdouble *values;
+
+  /* data */
+  SecondOrderFilter *filter;
+  gpointer history;
+  ProcessFunc process;
+  guint history_size;
+};
+
+struct _GstIirEqualizerClass
+{
+  GstAudioFilterClass audiofilter_class;
+};
+
+#endif /* __GST_IIR_EQUALIZER__ */