Version 3.2

src/PoleZero.cpp

@@ -0,0 +1,68 @@
+/*******************************************/
+/*  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));
+  outputs = (MY_FLOAT *) malloc(sizeof(MY_FLOAT));
+  b0Coeff = (MY_FLOAT) 1.0;
+  b1Coeff = (MY_FLOAT) 0.0;
+  a1Coeff = (MY_FLOAT) 0.0;
+  gain = (MY_FLOAT) 1.0;
+  this->clear();
+}
+
+PoleZero :: ~PoleZero()
+{
+  free(inputs);
+  free(outputs);
+}
+
+void PoleZero :: clear()
+{
+  inputs[0] = (MY_FLOAT) 0.0;
+  outputs[0] = (MY_FLOAT) 0.0;
+  lastOutput = (MY_FLOAT) 0.0;
+}
+
+void PoleZero :: setA1(MY_FLOAT coeff)
+{
+  a1Coeff = coeff;
+}
+
+void PoleZero :: setB0(MY_FLOAT coeff)
+{
+  b0Coeff = coeff;
+}
+
+void PoleZero :: setB1(MY_FLOAT coeff)
+{
+  b1Coeff = 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 in_sample = gain*sample;
+
+  lastOutput = b0Coeff*in_sample + b1Coeff*inputs[0] - a1Coeff*outputs[0];
+  inputs[0] = in_sample;
+  outputs[0] = lastOutput;
+
+  return lastOutput;
+}
+