Version 3.0

STK/PoleZero.cpp

@@ -0,0 +1,63 @@
+/*******************************************/
+/*  PoleZero (1-pole, 1-zero) Filter Class */
+/*  by Gary P. Scavone, 1999               */
+/*                                         */
+/*  See books on filters to understand     */
+/*  more about how this works.  Nothing    */
+/*  out of the ordinary in this version.   */
+/*******************************************/
+
+#include "PoleZero.h"
+
+PoleZero :: PoleZero() : Filter()
+{
+  inputs = (MY_FLOAT *) malloc(sizeof(MY_FLOAT));
+  zeroCoeff = (MY_FLOAT) 0.0;
+  poleCoeff = (MY_FLOAT) 0.0;
+  gain = (MY_FLOAT) 1.0;
+  this->clear();
+}
+
+PoleZero :: ~PoleZero()
+{
+  free(inputs);
+}
+
+void PoleZero :: clear()
+{
+  inputs[0] = (MY_FLOAT) 0.0;
+  lastOutput = (MY_FLOAT) 0.0;
+}
+
+void PoleZero :: setPoleCoeff(MY_FLOAT coeff)
+{
+  poleCoeff = coeff;
+}
+
+void PoleZero :: setZeroCoeff(MY_FLOAT coeff)
+{
+  zeroCoeff = coeff;
+}
+
+void PoleZero :: setGain(MY_FLOAT aValue)
+{
+  gain = aValue;
+}
+
+// PoleZero is one pole, one zero filter
+// Look it up in your favorite DSP text
+MY_FLOAT PoleZero :: tick(MY_FLOAT sample)
+{
+  MY_FLOAT temp;
+
+  // Direct Form II Implementation - only 1 state variable
+  temp = sample * gain;
+  temp += inputs[0] * poleCoeff;
+
+  lastOutput = temp;
+  lastOutput += (inputs[0] * zeroCoeff);
+  inputs[0] = temp;
+
+  return lastOutput;
+}
+