class_docstr: normalize image such as substract mean, divide std
      
class_docstr_tok: ["normalize","image","such","as","substract","mean",",","divide","std"]
code: def __call__(self, img):
      if isinstance(img, Image.Image):
          img = np.array(img)
  
      img = (img * self.scale - self.mean) / self.std
      return img
  
imports: import numpy
  import PIL
  from PIL import Image
label_desc: Use image node_id 2 for calling the NormalizeImage obj's underlying member method code with example usage: obj.__call__(img) and returns: img