KinectWithVRServer.MainWindow.CalculateFrameRate C# (CSharp) Method

        private static double CalculateFrameRate(TimeSpan currentTimeStamp, ref TimeSpan lastTimeStamp, ref List<double> oldIntervals)
        {
            double newInterval = currentTimeStamp.TotalMilliseconds - lastTimeStamp.TotalMilliseconds;
            lastTimeStamp = currentTimeStamp;

            if (oldIntervals.Count >= 20) //Computes a running average of 20 frames for stability
            {
                oldIntervals.RemoveAt(0);
            }
            oldIntervals.Add(newInterval);

            return (1.0 / oldIntervals.Average() * 1000.0);
        }