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

    @引數一: path_one: 第一張圖片的路徑
    @引數二: path_two: 第二張圖片的路徑
    @引數三: diff_save_location: 不同圖的儲存路徑
    """
    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')

執行結果：

第二種方法：

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)

如果兩張圖片完全相等，則返回結果為浮點型別“0.0”，如果不相同則返回結果值越大。

同樣用上面兩張圖片，執行結果為38，還是比較小的：

這樣就可以在自動化測試用例中呼叫該方法來斷言執行結果。

關於Pillow庫的詳細文件：