1 files changed, 55 insertions, 0 deletions
diff --git a/src/lp4pole_filter.c b/src/lp4pole_filter.c
new file mode 100644
index 0000000..7d54691
--- /dev/null
+++ b/src/lp4pole_filter.c
@@ -0,0 +1,55 @@
+/*
+  lp4pole filter admin.
+  Copyright 2011 David Robillard
+  Copyright 2003 Mike Rawes
+
+  See lp4pole_filter.h for history
+
+  This is free software: you can redistribute it and/or modify it
+  under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This software 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 software.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdlib.h>
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+#include "lp4pole_filter.h"
+
+LP4PoleFilter*
+lp4pole_new(double sample_rate)
+{
+	LP4PoleFilter* lpf;
+
+	lpf = (LP4PoleFilter*)malloc(sizeof(LP4PoleFilter));
+
+	if (lpf) {
+		lpf->inv_nyquist = 2.0f / sample_rate;
+		lp4pole_init(lpf);
+	}
+
+	return lpf;
+}
+
+void
+lp4pole_cleanup(LP4PoleFilter* lpf)
+{
+	if (lpf) {
+		free(lpf);
+	}
+}
+
+void
+lp4pole_init(LP4PoleFilter* lpf)
+{
+	lpf->in1        = lpf->in2 = lpf->in3 = lpf->in4 = 0.0f;
+	lpf->out1       = lpf->out2 = lpf->out3 = lpf->out4 = 0.0f;
+	lpf->max_abs_in = 0.0f;
+}