log-ratio 算子

import numpy as np
import matplotlib.pyplot as plt
from skimage import data
from skimage import io

# 读入图像，并转化为 float 格式
im1 = io.imread('D:\pic\Andasol_09051987.bmp')[:,:,0].astype(np.float64)
im2 = io.imread('D:\pic\Andasol_09122013.bmp')[:,:,0].astype(np.float64)

#生成差异图
# log-ratio 算子
im_di = abs(np.log((im1+1)/(im2+1)))

# 显示差异图
plt.subplot(133)
plt.imshow(im_di, 'gray')
plt.title('different image')