Envelope Follower

2 files changed, 30 insertions, 0 deletions

diff --git a/ofxMaxim/ofxMaxim/libs/maximilian.cpp b/ofxMaxim/ofxMaxim/libs/maximilian.cpp
index 5326172..a6420b2 100644
--- a/ofxMaxim/ofxMaxim/libs/maximilian.cpp
+++ b/ofxMaxim/ofxMaxim/libs/maximilian.cpp
@@ -1026,3 +1026,12 @@ double convert::mtof(int midinote) {
 	return mtofarray[midinote];
 }
 
+
+void maxiEnvelopeFollower::setAttack(double attackMS) {
+    attack = pow( 0.01, 1.0 / ( attackMS * maxiSettings::sampleRate * 0.001 ) );
+}
+
+void maxiEnvelopeFollower::setRelease(double releaseMS) {
+    release = pow( 0.01, 1.0 / ( releaseMS * maxiSettings::sampleRate * 0.001 ) );    
+}
+
diff --git a/ofxMaxim/ofxMaxim/libs/maximilian.h b/ofxMaxim/ofxMaxim/libs/maximilian.h
index 85c4c16..6f4d384 100755
--- a/ofxMaxim/ofxMaxim/libs/maximilian.h
+++ b/ofxMaxim/ofxMaxim/libs/maximilian.h
@@ -442,4 +442,25 @@ inline double maxiChorus::chorus(const double input, const unsigned int delay, c
     return (output1 + output2 + input) / 3.0;
 }
 
+class maxiEnvelopeFollower {
+public:
+    maxiEnvelopeFollower() {
+        setAttack(100);
+        setRelease(100);
+        env = 0;
+    }
+    void setAttack(double attackMS);
+    void setRelease(double releaseMS);
+    inline double play(double input) {
+        input = fabs(input);
+        if (input>env)
+            env = attack * (env - input) + input;
+        else
+            env = release * (env - input) + input;        
+        return env;
+    }
+private:
+    double attack, release, env;
+};
+
 #endif