Diff: ReverbUnit.hpp

Revision:

0:47656a949b95

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ReverbUnit.hpp	Tue Jul 15 09:26:17 2014 +0000
@@ -0,0 +1,78 @@
+//--------------------------------------------------------------
+// Reverb unit
+// Copyright (c) 2014 MIKAMI, Naoki,  2014/06/28
+//--------------------------------------------------------------
+
+#ifndef REVERB_UNIT_HPP
+#define REVERB_UNIT_HPP
+
+#include "mbed.h"
+
+namespace Mikami
+{
+    // Base class for reverb unit
+    template<int delay> class Reverb
+    {
+    private:
+        int ptr_;
+        float un_[delay];    // for delay
+
+        Reverb(const Reverb&);
+        Reverb& operator=(const Reverb&);
+    protected:
+        float Get() { return un_[ptr_]; }
+        void Set(float x)
+        {
+            un_[ptr_] = x;   
+            if (++ptr_ >=  delay) ptr_ = 0;
+        }
+    public:
+        // Constructor
+        Reverb() : ptr_(0) { Clear(); }
+
+        // Execute of filter (pure virtual function)
+        virtual float Execute(float x) = 0;
+
+        // Clear internal delay elements
+        void Clear()
+        { for (int n=0; n<delay; n++) un_[n] = 0; }
+    };
+
+    // Reverb unit using comb filter
+    template<int delay> class CombFilter : public Reverb<delay>
+    {
+    private:
+        const float G0_;
+    public:
+        // Constructor
+        CombFilter(float g) : G0_(g) {}
+
+        // Execute comb filter 
+        virtual float Execute(float x)
+        {
+            float yn = Reverb<delay>::Get();
+            Reverb<delay>::Set(x + G0_*yn);
+            return yn;
+         }
+    };
+
+    // Reverb unit using allpass filter
+    template<int delay> class AllPassFilter : public Reverb<delay>
+    {
+    private:
+        const float G0_;
+    public:
+        // Constructor
+        AllPassFilter(float g) : G0_(g) {}
+
+        // Execute allpass filter 
+        virtual float Execute(float x)
+        {
+            float un = x + G0_*Reverb<delay>::Get();
+            float yn = -G0_*un + Reverb<delay>::Get();
+            Reverb<delay>::Set(un);
+            return yn;
+        }
+    };
+}
+#endif  // REVERB_UNIT_HPP