text: #!/usr/bin/env python
  """
  reviews four bitwise operations: AND, OR, XOR, and NOT
  
  
  Parameters
  
  Usage
  
  Example
      $ python bitwise.py --image ../img/trex.png
  
  ## Explain
      - boolean algebra
  """
  import numpy as np
  import cv2
  
  def main():
      rectangle = np.zeros((300, 300), dtype="uint8")
      cv2.rectangle(rectangle, (25, 25), (275, 275), 255, -1)
      cv2.imshow("Rectangle", rectangle)
  
      circle = np.zeros((300,300), dtype="uint8")
      cv2.circle(circle, (150,150), 150, 255, -1)
      cv2.imshow("Circle", circle)
      cv2.waitKey(0)
  
      bitwiseAnd = cv2.bitwise_and(rectangle, circle)
      cv2.imshow("AND", bitwiseAnd)
      cv2.waitKey(0)
  
      bitwiseOr = cv2.bitwise_or(rectangle, circle)
      cv2.imshow("OR", bitwiseOr)
      cv2.waitKey(0)
  
      bitwiseXor = cv2.bitwise_xor(rectangle, circle)
      cv2.imshow("XOR", bitwiseXor)
      cv2.waitKey(0)
  
      bitwiseNot = cv2.bitwise_not(circle)
      cv2.imshow("NOT", bitwiseNot)
      cv2.waitKey(0)
  
  if __name__=="__main__":
      main()