python通过PIL库批量重置图片大小

原像素大小也会改变美中不足

import os
from PIL import Image
import struct
import sys
#  python3 /Users/rex/Downloads/未命名文件夹/origin.py /Users/rex/Downloads/未命名文件夹

path = sys.argv[1] 
nImgW = 200
nImgH = 200
maxImgW = 0
maxImgH = 0
def list_pic(dirpath):
    for root, dirs, fs in os.walk(dirpath):
        for f in fs:
            if f.endswith('.png') or f.endswith('.jpg'):
                yield os.path.join(root, f)
 
def calcMaxWH(dirpath):
    global maxImgW,maxImgH
    for f in list_pic(dirpath):
        img = Image.open(f)
        (w,h) = img.size 
        maxImgW = max(w,maxImgW)
        maxImgH = max(h,maxImgH)


               
           
def resizeImage(dirpath):
    with open('resize_pic.output.log', 'w') as log:
        for f in list_pic(dirpath):
            img = Image.open(f)
            (w,h) = img.size
            nw = maxImgW
            nh = maxImgH
            print( (w, h),'->',(nw,nh), f)
            log.write("%s | (%d,%d)-> (%d,%d)\n"%(f,w, h,nw,nh))
            # img = img.resize((nw,nh),Image.ANTIALIAS)
            img.thumbnail((nw,nh),Image.ANTIALIAS) #只能缩小不能放大？
            print(f)
            img.show()
            img.save(f)

if '__main__' == __name__:
    calcMaxWH(path)
    resizeImage(path)