python批量裁剪图片

# coding: utf-8
from PIL import Image
import os
import os.path
import numpy as np
import cv2
#指明被遍历的文件夹
rootdir=r'/home/mmediting/data/4K/valid/lr/000'
for parent, dirnames, filenames in os.walk(rootdir):#遍历每一张图片
    filenames.sort()
    for filename in filenames:
        #print('parent is :' + parent)#parent is :/home/mmediting/data/4K/valid/gt/000
        #print('filename is :' + filename)#filename is :00000084.png
        currentPath = os.path.join(parent, filename)
        print('the fulll name of the file is :' + currentPath)#the fulll name of the file is :/home/mmediting/data/4K/valid/gt/000/00000084.png
   
        img = Image.open(currentPath)
        #print (img.format, img.size, img.mode)#PNG (3840, 2160) RGB
        
        #设置左、上、右、下的像素
        #gt
        #box1 = (0, 0, 1920, 1080)
        # box2 = (0, 1080, 1920, 2160)
        # box3 = (1920, 0, 3840, 1080)
        # box4 = (1920, 1080, 3840, 2160)
        #lr
        box1=(0,0,480,270)
        box2=(0,270,480,540)
        box3=(480,0,960,270)
        box4=(480,270,960,540)
        
        image1 = img.crop(box4) # 图像裁剪
        ##存储裁剪得到的图像
        image1.save(r"/home/mmediting/data/4K/valid_crop/lr/020"+'/'+filename) 

将一个大图切成4份
仅需更改
image1 = img.crop(box4) # 图像裁剪

以及 径即可