def METHOD_NAME(self):
    """
    Calculates FPS value based on :func:`nextIter` calls, being the FPS of processing loop
    Returns:
        float: Calculated FPS or :code:`0.0` (default in case of failure)
    """
    if self._start is None or self._timestamp is None:
        return 0.0
    timeDiff = self._timestamp - self._start
    return self._iterCnt / timeDiff if timeDiff != 0 else 0.0