code: def _color_twist(self, images):
      def random_value():
          value = random.uniform(1.0, 1.5)
          coin = random.randrange(2)
          return coin * value + (1 - coin) * (1.0 / value)
  
      for i in range(self._batch_size):
          image = images[i, ...]
  
          hue = random.uniform(-18.0, 18.0)
          image = cv2.cvtColor(image, cv2.COLOR_RGB2HSV)
          image[..., 0] += hue
          image = cv2.cvtColor(image, cv2.COLOR_HSV2RGB)
  
          brightness = random_value()
          contrast = random_value()
          image *= brightness * contrast
          image += (0.5 - 0.5 * contrast) * brightness
  
          images[i, ...] = image
  
file_path: DALI/docs/examples/use_cases/tensorflow/yolov4/src/np/pipeline.py
imports: from .coco import COCO
  import numpy
  import tensorflow
  import os
  import cv2
  import random
label_desc: Use image node_id 6 for calling the YOLOv4PipelineNumpy obj's underlying member method code with example usage: obj._color_twist(images) and returns: unknown