code: def send_video_frame(self, frame, frame_counter=None):
          
          if frame_counter is None:
              frame_counter = self.frame_counter
              self.frame_counter += 1
  
          self.q_video.put((frame_counter, frame))
docs: send frame of shape (height, width, 3)
          with values between 0 and 1
  
          :param frame: array containing the frame.
          :type frame: numpy array with shape (height, width, 3)
              containing values between 0.0 and 1.0
          :param frame_counter: frame position number within stream.
              Provide this when multi-threading to make sure frames don't
              switch position
          :type frame_counter: int