jpg格式图像转为png或者其它格式

import cv2
import os

for fi in os.listdir(\'./CCimage/\'):
    I=cv2.imread(\'./CCimage/\'+fi)
    cv2.imwrite(\'./CCimage/\'+fi.split(\'.\')[0]+\'.png\',I)
    os.remove(\'./CCimage/\'+fi)
    print fi