new_contents: """ Apply different filters here """
  
  import cv2  # import OpenCV 3 module
  
  camera = cv2.VideoCapture(0)  # get default camera
  mode = 2  # default mode, apply Canny edge detection
  while True:
      ok, frame = camera.read()  # read frame
      if ok:  # frame is read correctly
          if mode == 2:
              frame = cv2.Canny(frame, 100, 200)  # Canny edge detection
          cv2.imshow('My camera', frame)  # show frame
      key = cv2.waitKey(1) & 0xff  # read keystroke
      if key == 27: break  # <Escape> key pressed, exit from cycle
      if key == ord('1'): mode = 1  # show unchanged frame
      if key == ord('2'): mode = 2  # apply Canny edge detection
  
  camera.release()  # release web camera
  cv2.destroyAllWindows()
  
subject: Apply different filters for web camera image