util.py 文件源码

def rmsdiff(im1, im2):
    im1 = im1.convert("RGBA")
    im2 = im2.convert("RGBA")

    diff = ImageChops.difference(im1, im2)
    h = diff.histogram()


    blah = np.array(h, dtype=int)
    okay = (np.arange(1024)%256)**2
    rms = sqrt(np.sum(blah*okay)/float(im1.size[0] * im1.size[1]))

    # sq = [value*((idx%256)**2) for idx, value in enumerate(h)]
    # sum_of_squares = sum(sq)
    # rms = sqrt(sum_of_squares/float(im1.size[0] * im1.size[1]))

    return rms