/** Removes the listener from receiving output samples */
 public void removeListener(Listener<ComplexSample> listener) {
   mHalfBandFilter.setListener(null);
 }
 public Listener<ComplexSample> getListener() {
   return mHalfBandFilter.getListener();
 }
 /** Adds a listener to receive output samples */
 public void setListener(Listener<ComplexSample> listener) {
   mHalfBandFilter.setListener(listener);
 }