--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.3/spandsp-0.0.3/src/spandsp/complex_filters.h	Fri Jun 25 16:00:21 2010 +0200
@@ -0,0 +1,73 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * complex_filters.h
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2003 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: complex_filters.h,v 1.6 2006/10/24 13:45:28 steveu Exp $
+ */
+
+#if !defined(_COMPLEX_FILTERS_H_)
+#define _COMPLEX_FILTERS_H_
+
+typedef struct filter_s filter_t;
+
+typedef float (*filter_step_func_t)(filter_t *fi, float x);
+
+typedef struct
+{
+    int                 nz;
+    int                 np;
+    filter_step_func_t  fsf;
+} fspec_t;
+
+struct filter_s
+{
+    fspec_t             *fs;
+    float               sum;
+    int                 ptr;		/* for moving average filters only */
+    float               v[];
+};
+
+typedef struct
+{
+    filter_t            *ref;
+    filter_t            *imf;
+} cfilter_t;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+filter_t *filter_create(fspec_t *fs);
+void filter_delete(filter_t *fi);
+float filter_step(filter_t *fi, float x);
+
+cfilter_t *cfilter_create(fspec_t *fs);
+void cfilter_delete(cfilter_t *cfi);
+complexf_t cfilter_step(cfilter_t *cfi, const complexf_t *z);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+/*- End of file ------------------------------------------------------------*/