python 检测屏幕指定区域 有变化即截图

from PIL import ImageChops # $ pip install pillow 
from pyscreenshot import grab # $ pip install pyscreenshot 
from datetime import datetime
import time,sys,re
im = grab(bbox=(160,180,1760,1080))
a=0
while True: # http://effbot.org/zone/pil-comparing-images.htm 
    diff = ImageChops.difference(grab(bbox=(160,180,1760,1080)), im) 
    bbox = diff.getbbox()
    print(bbox)
    if bbox is not None: # exact comparison
        img = grab(bbox=(160,180,1760,1080))
        now = datetime.now()
        date_time = now.strftime("%Y%m%d%H%M%S")
        te2=r"e:/te/tu/"+date_time+".jpg"
        img.save(te2)
        time.sleep(2)
        a=a+1
        print(a)
        im = grab(bbox=(160,180,1760,1080))
        
    else:
        time.sleep(2)