code: def __call__(self, im):
      im, (ratio_h, ratio_w) = self.resize_image_type(im)
      im = self.normalize(im)
      im = im[np.newaxis, :]
      return [im, (ratio_h, ratio_w)]
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import sys
  import cv2
  import numpy
  import pyclipper
  from PIL import ImageDraw
  from shapely.geometry import Polygon
label_desc: Use image node_id 4 for calling the DBPreProcess obj's underlying member method code with example usage: obj.__call__(im) and returns: list