批量图片转换成bmp格式

import Image
##im = Image.open(‘BtnWrite.Image.gif‘)
##im.save(‘BtnWrite.Image.bmp‘)
##

import os
extension = [‘.bmp‘]
listfile = os.listdir(os.getcwd())
for each in listfile:
    filename = each
    print filename
    im = Image.open(filename)
    #全部转换成RGB模式
    im = im.convert(‘RGB‘)
    #处理为转换成功的RGBA模式
    if len(im.split()) == 4:
        r,g,b,a = im.split()
        im = Image.merge("RGB",(r,g,b))
        im.save(filename[:-3]+extension[0])
    else:
        im.save(filename[:-3]+extension[0])