A way to artificially throttle FPS useful for video processing applications

FpsLimiter.cs

using System.Diagnostics;

Console.WriteLine("Hello, World!");

var limiter = new FpsLimiter(60);

var rejected = new List<int>();
var accepted = new List<int>();

var watch = Stopwatch.StartNew();
var count = 0d;

while (true)
{
    if (count++ > 50)
    {
        break;
    }

    limiter.Wait();
}

Console.WriteLine($"Average FPS: {1000d / (watch.ElapsedMilliseconds / count):N}");

public class FpsLimiter
{
    private readonly Stopwatch _stopwatch = new Stopwatch();
    private readonly double _frameIntervalMs;
    private double _nextFrameTimeMs;

    public FpsLimiter(double desiredFps)
    {
        _frameIntervalMs = 1000.0 / desiredFps;
        _nextFrameTimeMs = _stopwatch.Elapsed.TotalMilliseconds + _frameIntervalMs;
        _stopwatch.Start();
    }

    public void Wait()
    {
        var currentTimeMs = _stopwatch.Elapsed.TotalMilliseconds;

        if (_nextFrameTimeMs > currentTimeMs)
        {
            SpinWait.SpinUntil(() => _stopwatch.ElapsedMilliseconds >= _nextFrameTimeMs);
        }

        _nextFrameTimeMs += _frameIntervalMs;
    }
}