from PIL import Image
from PIL import ImageChops 
def compare_images(path_one, path_two, diff_save_location):
  """
  比較圖片，如果有不同則生成展示不同的圖片
  @參數(shù)一: path_one: 第一張圖片的路徑
  @參數(shù)二: path_two: 第二張圖片的路徑
  @參數(shù)三: diff_save_location: 不同圖的保存路徑
  """
  image_one = Image.open(path_one)
  image_two = Image.open(path_two)
  try: 
    diff = ImageChops.difference(image_one, image_two)
    if diff.getbbox() is None:
    # 圖片間沒有任何不同則直接退出
      print("【+】We are the same!")
    else:
      diff.save(diff_save_location)
  except ValueError as e:
    text = ("表示圖片大小和box對應的寬度不一致，參考API說明：Pastes another image into this image."
        "The box argument is either a 2-tuple giving the upper left corner, a 4-tuple defining the left, upper, "
        "right, and lower pixel coordinate, or None (same as (0, 0)). If a 4-tuple is given, the size of the pasted "
        "image must match the size of the region.使用2緯的box避免上述問題")
    print("【{0}】{1}".format(e,text))
if __name__ == '__main__':
  compare_images('1.png',
          '2.png',
          '我們不一樣.png')

from PIL import Image
import math
import operator
from functools import reduce
def image_contrast(img1, img2):
  image1 = Image.open(img1)
  image2 = Image.open(img2)
  h1 = image1.histogram()
  h2 = image2.histogram()
  result = math.sqrt(reduce(operator.add, list(map(lambda a,b: (a-b)**2, h1, h2)))/len(h1) )
  return result
if __name__ == '__main__':
  img1 = "./1.png" # 指定圖片路徑
  img2 = "./2.png"
  result = image_contrast(img1,img2)
  print(result)