protected override Mat ProcessFrame(ref Mat frame)
    {
        frameCount++;
        Mat rez = new Mat();
        frame.CopyTo(rez);
        prevFrame = new Mat();
        nextFrame = new Mat();

        CvInvoke.CvtColor(frame, nextFrame, Emgu.CV.CvEnum.ColorConversion.Bgr2Gray);
        CvInvoke.CvtColor(frame, prevFrame, Emgu.CV.CvEnum.ColorConversion.Bgr2Gray);


        //CvInvoke.CalcOpticalFlowPyrLK(); ???

        return rez;

    }