new filter subdir for standard audio filters first filter uses code from vorbis to implement an iir filter not optimi...

Original commit message from CVS:
new filter subdir for standard audio filters
first filter uses code from vorbis to implement an iir filter
not optimized yet, iir code uses doubles and plugin uses float

1 files changed, 37 insertions, 0 deletions

diff --git a/gst/filter/iir.h b/gst/filter/iir.h
new file mode 100644
index 00000000..241cc1d2
--- /dev/null
+++ b/gst/filter/iir.h
@@ -0,0 +1,37 @@
+/********************************************************************
+ *                                                                  *
+ * THIS FILE IS PART OF THE Ogg Vorbis SOFTWARE CODEC SOURCE CODE.  *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
+ * THE GNU PUBLIC LICENSE 2, WHICH IS INCLUDED WITH THIS SOURCE.    *
+ * PLEASE READ THESE TERMS DISTRIBUTING.                            *
+ *                                                                  *
+ * THE OggSQUISH SOURCE CODE IS (C) COPYRIGHT 1994-2000             *
+ * by Monty <monty@xiph.org> and The XIPHOPHORUS Company            *
+ * http://www.xiph.org/                                             *
+ *                                                                  *
+ ********************************************************************
+
+  function: Direct Form I, II IIR filters, plus some specializations
+  last mod: $Id$
+
+ ********************************************************************/
+
+#ifndef _V_IIR_H_
+#define _V_IIR_H_
+
+typedef struct {
+  int stages;
+  double *coeff_A;
+  double *coeff_B;
+  double *z_A;
+  double *z_B;
+  int ring;
+  double gain;
+} IIR_state;
+
+void IIR_init(IIR_state *s,int stages,double gain, double *A, double *B);
+void IIR_clear(IIR_state *s);
+double IIR_filter(IIR_state *s,double in);
+double IIR_filter_ChebBand(IIR_state *s,double in);
+
+#endif