class_docstr: normalize image
  Args:
      mean (list): im - mean
      std (list): im / std
      is_scale (bool): whether need im / 255
      is_channel_first (bool): if True: image shape is CHW, else: HWC
class_docstr_tok: ["normalize","image","Args",":","mean","(","list",")",":","im","-","mean","std","(","list",")",":","im","\/","std","is_scale","(","bool",")",":","whether","need","im","\/","255","is_channel_first","(","bool",")",":","if","True",":","image","shape","is","CHW",",","else",":","HWC"]
code: def __init__(self, mean, std, is_scale=True):
      self.mean = mean
      self.std = std
      self.is_scale = is_scale
  
imports: import cv2
  import numpy
label_desc: Use image node_id 1 to create a new NormalizeImage object from inherited base classes: object with example: obj = NormalizeImage(mean, std, is_scale)