python实现图片批量压缩程序

 本文实例为大家分享了python实现图片批量压缩程序的具体代码，供大家参考，具体内容如下

说明

• 运行环境：Win10 Pycharm

• 程序没有用到面向对象编程方法，只是简单的面向过程设计

• 用到的模块：PIL、os、sys

• 使用方法： 在Pycharm的terminal中输入”python xxx.py source_dir dest_dir”就可以把source_dir中的图片文件进行压缩并保存到dest_dir中
  

源码

from PIL import Image
import os
import sys

# 定义可以识别的图片文件类型，可以自行扩充
valid_file_type = ['.jpg', '.png']
# 定义压缩比，数值越大，压缩越小
SIZE_normal = 1.0
SIZE_small = 1.5
SIZE_more_small = 2.0

def make_directory(directory):
 """创建目录"""
 os.makedirs(directory)

def directory_exists(directory):
 """判断目录是否存在"""
 if os.path.exists(directory):
   return True
 else:
   return False

def list_img_file(directory):
 """列出目录下所有文件，并筛选出图片文件列表返回"""
 old_list = os.listdir(directory)
 # print old_list
 new_list = []
 for filename in old_list:
   if os.path.isfile(filename):
     f, e = os.path.splitext(filename)
     if e in valid_file_type:
       new_list.append(filename)
     else:
       pass
   else:
     pass
 # print new_list
 return new_list

def print_help():
 print """
 This program helps compress many image files
 you can choose which scale you want to compress your img(jpg/png/etc)
 1) normal compress(4M to 1M around)
 2) small compress(4M to 500K around)
 3) smaller compress(4M to 300K around)
 """

def compress(choose, des_dir, file_list):
 """压缩算法，img.thumbnail对图片进行压缩，还可以改变宽高数值进行压缩"""
 if choose == '1':
   scale = SIZE_normal
 if choose == '2':
   scale = SIZE_small
 if choose == '3':
   scale = SIZE_more_small
 for infile in file_list:
   img = Image.open(infile)
   # size_of_file = os.path.getsize(infile)
   w, h = img.size
   img.thumbnail((int(w/scale), int(h/scale)))
   img.save(des_dir + '/' + infile)

if __name__ == "__main__":
 src_dir, des_dir = sys.argv[1], sys.argv[2]
 if directory_exists(src_dir):
   if not directory_exists(des_dir):
     make_directory(des_dir)
   # business logic
   file_list = list_img_file(src_dir)
   # print file_list
   if file_list:
     print_help()
     choose = raw_input("enter your choice:")
     compress(choose, des_dir, file_list)
   else:
     pass
 else:
   print "source directory not exist!"

来源：https://blog.csdn.net/qq_22187919/article/details/52551526