diff src/scheme/filter.scm @ 0:bf79fb79ee13

Initial Mercurial check in.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/scheme/filter.scm	Tue Jan 17 17:50:20 2012 +0000
@@ -0,0 +1,32 @@
+(define (hp x)
+	; Normaliser used as high pass filter to remove slow variations
+	(define n (node "phase1" (NormaliseVector. x)))
+	(addtasks n)
+	(.output n)
+)
+
+(define (lp x)	
+	; Normaliser used as low pass filter to remove fast variations
+	(define n (node "lp" (NormaliseVector. x)))
+	(addtasks n)
+	(.mean n)
+)
+
+(define (bp x) (lp (hp x)))
+
+
+(define (smooth-signal sig) (addtask
+	(node (.getNode sig)
+		(GenerateDouble. (VDouble. "smoothed")
+			(FilteredGenerator. (DoubleGenerator. sig)	
+				(IIRFilter.
+					; two element double array controlled by VDouble
+					(let ((a (double[] #(1 0)))
+							(p (samer.core.types.VDouble. "smoothness" 1.0)))
+						(on-change p 
+							(let ((r (Math.exp (- (.get p)))))
+								(double[] a 0 r)
+								(double[] a 1 (- 1 r))))
+						(.changed p)
+						a )))))))
+