# 填充新的 image
def fill_image(image):
 width, height = image.size
 _length = width
 if height > width:
  _length = height
 new_image = Image.new(image.mode, (_length, _length), color='white')
 if width > height:
  new_image.paste(image, (0, int((_length - height) / 2)))
 else:
  new_image.paste(image, (int((_length - width) / 2), 0))
 return new_image

# 裁剪 image
def cut_image(image):
 width, height = image.size
 _width = int(width / 3)
 box_list = []
 for i in range(0, 3):
  for j in range(0, 3):
   box = (j * _width, i * _width, (j + 1) * _width, (i + 1) * _width)
   box_list.append(box)
   image_list = [image.crop(box) for box in box_list]
 return image_list

# 将 image 列表的里面的图片保存
def save_images(image_list, res_dir):
 index = 1
 if not os.path.exists(res_dir):
  os.mkdir(res_dir)
 for image in image_list:
  new_name = os.path.join(res_dir, str(index) + '.png')
  image.save(new_name, 'PNG')
  index += 1