Python实例2-获取某文件夹下指定类型的图片名，完成图片格式的转换并保存

import random  import os import os.path as osp  from PIL import Imagedataset_dir='/home/walden/pytorch/uiuc/data/VOC/cls'def file_name(file_dir):         L=[]         for root, dirs, files in os.walk(file_dir):            for file in files:                if os.path.splitext(file)[1] == '.png':                    #L.append(os.path.join(root, file))                  L.append(file)      return L    my_filename=file_name(dataset_dir)    random.shuffle(my_filename)  f=open('all.txt','w')  for i in my_filename:      #k=' '.join([str(j) for j in i])      f.write(i+"\n")  f.close()for i in my_filename:    path=osp.join(dataset_dir, '%s' % i)    img=Image.open(path)    img.save(path[0:len(path)-4]+'.bmp')