new_contents: # coding:utf-8
  import cv2
  
  cap = cv2.VideoCapture(0)
  cascade_path = "../opencv/data/haarcascades/haarcascade_frontalface_default.xml"
  cascade = cv2.CascadeClassifier(cascade_path)
  
  _response, frame = cap.read()
  minsize = (int(frame.shape[0] * 0.08), int(frame.shape[1] * 0.08))
  
  while True:
      _response, frame = cap.read()
      facerect = cascade.detectMultiScale(frame, scaleFactor=1.11, minNeighbors=3, minSize=minsize)
  
      rect_count = len(facerect)
  
      if rect_count >= 2:
          halv_count = int(rect_count/2)
          rfacerect = facerect[::-1]
          facerect  = facerect[:halv_count]
          rfacerect = rfacerect[:halv_count]
  
          for (rect1, rect2) in zip(facerect, rfacerect):
              x1, y1, w1, h1 = rect1
              x2, y2, w2, h2 = rect2
  
              face1 = frame[y1:y1+h1, x1:x1+w1]
              face2 = frame[y2:y2+h2, x2:x2+w2]
  
              face1 = cv2.resize(face1, (w2, h2))
              face2 = cv2.resize(face2, (w1, h1))
  
              frame[y1:y1+h1, x1:x1+w1] = face2
              frame[y2:y2+h2, x2:x2+w2] = face1
  
      cv2.waitKey(1)
      cv2.imshow("face camera", frame)
  
subject: Add new sample