方式1：pillow 库
需安装：pip install pillow
1 from PIL import Image
2 from selenium import webdriver
3
4
5 class ImageCompare(object):
6 '''
7 本类实现了对两张图片通过像素比对的算法，获取文件的像素个数大小，
8 然后使用循环的方式将两张图片的所有项目进行一一对比，并计算比对结果的相似度
9 '''
10
11 def make_regular_image(self, img, size=(256, 256)):
12 return img.resize(size).convert("RGB")
13
14 def split_image(self, img, part_size=(64, 64)):
15 # 将图片按给定大小切分
16 w, h = img.size
17 pw, ph = part_size
18 assert w % pw == h % ph == 0
19 return [img.crop((i, j, i + pw, j + ph)).copy() for i in range(0, w, pw) for j in range(0, h, ph)]
20
21 def hist_similar(self, lh, rh):
22 # 统计切分后每部分图片的相似度频率曲线
23 assert len(lh) == len(rh)
24 return sum(1 - (0 if l == r else float(abs(l - r)) / max(l, r)) for l, r in zip(lh, rh)) / len(lh)
25
26 def calc_similar(self, li, ri):
27 # 计算两张图片的相似度
28 return sum(self.hist_similar(l.histogram(), r.histogram()) for l, r in zip(self.split_image(li), self.split_image(ri))) / 16.0
29
30 def calc_similar_by_path(self, lf, rf):
31 li, ri = self.make_regular_image(Image.open(lf)), self.make_regular_image(Image.open(rf))
32 return self.calc_similar(li, ri)
33
34
35 if __name__ == "__main__":
36 IC = ImageCompare()
37 driver = webdriver.Chrome()
38 url = "http://www.sogou.com"
39 driver.get(url)
40 driver.save_screenshot("e:\\sogou1.png")
41 driver.get(url)
42 driver.save_screenshot("e:\\sogou2.png")
43 print ("%.2f%%" % (IC.calc_similar_by_path('e:\\sogou1.png','e:\\sogou2.png')*100)) # 99.84%
44 driver.quit()
方式2：scipy 库
1 from scipy.misc import imread, imsave, imresize
2
3
4 a = imread("E:\\sogou1.png")
5 b = imread("E:\\sogou2.png")
6
7 # 像素的差异数量
8 diff = sum((a == b).reshape(-1)) - sum((a != b).reshape(-1))
9 total = a.shape[0] * a.shape[1] * a.shape[2]
10 close = diff / total
11
12 print("相似度 = {:.2%}".format(close))