python批量修改图片后缀（png到jpg）

python批量修改图片后缀（png到jpg）

import os

import string

dirName ="D:\JPEGImages\\"        #最后要加双斜杠，不然会报错

li=os.listdir(dirName)

for filenamein li:

    newname = filename

    newname = newname.split(".")

    if newname[-1]=="png":

            newname[-1]="jpg"

            newname =str.join(".",newname)#这里要用str.join

            filename = dirName+filename

            newname = dirName+newname

            os.rename(filename,newname)

            print(newname,"updated successfully")