JPEG2jpg

import os
import string

dir1 = "11/"
dir2 = "test/"

# 读取函数，用来读取文件夹中的所有函数，输入参数是文件名
def read_directory(directory_name):
    i=0
    for filename in os.listdir(directory_name):
        print(filename)
        if "DS_Store" in filename:
            continue
        newname = filename
        newname = newname.split(".")
        if newname[-1]=="JPEG":
            i=i+1
            newname[-1]="jpg"
            newname[-2]=str(i)
            newname = str.join(".",newname) #这里要用str.join
            
            
            
            filename = dir1+filename
            newname = dir2+newname
            os.rename(filename,newname)


read_directory("./11")