Version 4.0

src/PitShift.cpp

@@ -0,0 +1,90 @@
+/***************************************************/
+/*! \class PitShift
+    \brief STK simple pitch shifter effect class.
+
+    This class implements a simple pitch shifter
+    using delay lines.
+
+    by Perry R. Cook and Gary P. Scavone, 1995 - 2002.
+*/
+/***************************************************/
+
+#include "PitShift.h"
+#include <iostream.h>
+#include <math.h>
+
+PitShift :: PitShift()
+{
+  delay[0] = 12;
+  delay[1] = 512;
+  delayLine[0] = new DelayL(delay[0], (long) 1024);
+  delayLine[1] = new DelayL(delay[1], (long) 1024);
+  effectMix = (MY_FLOAT) 0.5;
+  rate = 1.0;
+}
+
+PitShift :: ~PitShift()
+{
+  delete delayLine[0];
+  delete delayLine[1];
+}
+
+void PitShift :: setEffectMix(MY_FLOAT mix)
+{
+  effectMix = mix;
+  if ( mix < 0.0 ) {
+    cerr << "PitShift: setEffectMix parameter is less than zero!" << endl;
+    effectMix = 0.0;
+  }
+  else if ( mix > 1.0 ) {
+    cerr << "PitShift: setEffectMix parameter is greater than 1.0!" << endl;
+    effectMix = 1.0;
+  }
+}
+
+void PitShift :: setShift(MY_FLOAT shift)
+{
+  if (shift < 1.0)    {
+    rate = 1.0 - shift; 
+  }
+  else if (shift > 1.0)       {
+    rate = 1.0 - shift;
+  }
+  else {
+    rate = 0.0;
+    delay[0] = 512;
+  }
+}
+
+MY_FLOAT PitShift :: lastOut() const
+{
+  return lastOutput;
+}
+
+MY_FLOAT PitShift :: tick(MY_FLOAT input)
+{
+  delay[0] = delay[0] + rate;
+  while (delay[0] > 1012) delay[0] -= 1000;
+  while (delay[0] < 12) delay[0] += 1000;
+  delay[1] = delay[0] + 500;
+  while (delay[1] > 1012) delay[1] -= 1000;
+  while (delay[1] < 12) delay[1] += 1000;
+  delayLine[0]->setDelay((long)delay[0]);
+  delayLine[1]->setDelay((long)delay[1]);
+  env[1] = fabs(delay[0] - 512) * 0.002;
+  env[0] = 1.0 - env[1];
+  lastOutput =  env[0] * delayLine[0]->tick(input);
+  lastOutput += env[1] * delayLine[1]->tick(input);
+  lastOutput *= effectMix;
+  lastOutput += (1.0 - effectMix) * input;
+  return lastOutput;
+}
+
+MY_FLOAT *PitShift :: tick(MY_FLOAT *vector, unsigned int vectorSize)
+{
+  for (unsigned int i=0; i<vectorSize; i++)
+    vector[i] = tick(vector[i]);
+
+  return vector;
+}
+