code: def DSP_capture_add_samples_stereo(self,new_data_left,new_data_right):
          
          self.capture_sample_count = self.capture_sample_count + len(new_data_left) + len(new_data_right)
          if self.Tcapture > 0:
              self.data_capture_left = np.hstack((self.data_capture_left,new_data_left))
              self.data_capture_right = np.hstack((self.data_capture_right,new_data_right))
              if (len(self.data_capture_left) > self.Ncapture):
                  self.data_capture_left = self.data_capture_left[-self.Ncapture:]
              if (len(self.data_capture_right) > self.Ncapture):
                  self.data_capture_right = self.data_capture_right[-self.Ncapture:]
docs: Append new samples to the data_capture_left array and the data_capture_right
          array and increment the sample counter. If length reaches Tcapture, then the 
          newest samples will be kept. If Tcapture = 0 then new values are not appended 
          to the data_capture array.