python实现对图像进行指定区域裁剪

from PIL import Image
import os
import os.path


# 定义文件所在文件夹
image_dir = './test'
for parent, dir_name, file_names in os.walk(image_dir):  # 遍历每一张图片
    for filename in file_names:
        pic_name = os.path.join(parent, filename)
        image = Image.open(pic_name)
        _width, _height = image.size
        print(_width, _height)

        # 定义裁剪范围(left, upper, right, lower)
        box = image.crop((960, 200, 1800, 1425))
        filename = 'cut_' + filename
        box.save('./test/%s' % filename)
    print('Done!')