code: def _heighten(self, resource):
          
          original_width, original_height = resource.size
  
          target_height = self.value
          target_width = int((float(target_height) / original_height) * original_width)
  
          resource = resource.resize((target_width, target_height), Image.ANTIALIAS)
  
          return resource
docs: Change image size by height
          :param resource: Image
          :return: Image