for im in imlist:
    imarr = numpy.array(Image.open(im), dtype=numpy.float)
arr = arr + imarr / N
arr = numpy.array(numpy.round(arr), dtype=numpy.uint8)
out = Image.fromarray(arr, mode='RGB')
out.save('Average.png')
out.show()
How to get an average picture from 100 pictures using PIL?