dvsproc.py 文件源码

def cal_running_std(event_freq, n=16):
    """Calculate running standard deviation.

    Parameters
    ----------
    event_freq : numpy.ndarray
        Event frequency count in given window
    n : int
        Running window for computing STD

    Returns
    -------
    o : numpy.ndarray
        Running standard deviation of given event frequency array
    """
    q = event_freq[:, 1]**2
    q = np.convolve(q, np.ones((n, )), mode="valid")
    s = np.convolve(event_freq[:, 1], np.ones((n, )), mode="valid")
    o = (q-s**2/n)/float(n-1)

    return o