public void GrayscaleTest() { foreach (var a in Enumerable.Range(0, 256)) { foreach (var r in Enumerable.Range(0, 256)) { foreach (var g in Enumerable.Range(0, 256)) { foreach (var b in Enumerable.Range(0, 256)) { var t = Color.FromArgb(a, r, g, b); Assert.AreEqual(ImageFilters.GrayscaleFilter((uint)t.ToArgb()), GrayscaleFilter(t).ToArgb()); } } } } }