msssim.py 文件源码

def _FSpecialGauss(size, sigma):
    """Function to mimic the 'fspecial' gaussian MATLAB function."""
    radius = size // 2
    offset = 0.0
    start, stop = -radius, radius + 1
    if size % 2 == 0:
        offset = 0.5
        stop -= 1
    x, y = np.mgrid[offset + start:stop, offset + start:stop]
    assert len(x) == size
    g = np.exp(-((x ** 2 + y ** 2) / (2.0 * sigma ** 2)))
    return g / g.sum()