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        readonly static int white = Color.White.ToArgb();
        readonly static int black = Color.Black.ToArgb();
        readonly static Random NoiseRnd = new Random();
        private static DirectBitmap GetStaticNoise(int width, int height)
        {
            var bitmap = new DirectBitmap(width, height);
            for (int y = 0; y < height; y++)
            {
                for (int x = 0; x < width; x++)
                {
                    var rnd = NoiseRnd.Next(0, 2);

                    bitmap.SetPixel(x, y, rnd % 2 == 0 ? white : black);
                }
            }

            return bitmap;
        }

        readonly static int white = Color.White.ToArgb();
        readonly static int black = Color.Black.ToArgb();
        readonly static Random NoiseRnd = new Random();
        private static DirectBitmap GetStaticNoise(int width, int height)
        {
            var bitmap = new DirectBitmap(width, height);
            for (int y = 0; y < height; y++)
            {
                for (int x = 0; x < width; x++)
                {
                    var rnd = NoiseRnd.Next(0, 2);

                    bitmap.SetPixel(x, y, rnd == 0 ? white : black);
                }
            }

            return bitmap;
        }

In the end, the real winner is white*0, but... that won't work in opaque ARGB colors, where A is 255.

However, if your loop is tight enough and dataset fits into cpu cache, results will become

In the end, the real winner is white*0, but... that won't work in opaque ARGB colors, where A is 255.

TLDR: microoptimizations are hard and CPU doing its own tricks makes it even harder :)

To clarify on using Ternary Operator as performance optimization: Two-element array is twice as fast as full If statement, and Ternary Operator is ~30% faster than array. Original code used modulo 2 to check parity, but with Random already returning only 0 or 1 it can be used without modulo for small performance gain. Have in mind that (ab)using array indexes as logic (pointers) should work better in native code, without all the fancy memory management of .NET. Or it might not, depending on performance tricks done by CPU's themselves. Micro optimizations are tricky.

To clarify on using Ternary Operator as performance optimization: Two-element array is twice as fast as full If statement, and Ternary Operator is ~30% faster than array. Original code used modulo 2 to check parity, but with Random already returning only 0 or 1 it can be used without modulo for small performance gain.

But if you reorder IF statements slightly, you can squeeze out a bit more performance: Have in mind that (ab)using array indexes as logic (pointers) should work better in native code, without all the fancy memory management of .NET. Or it might not, depending on performance tricks done by CPU's themselves. Micro optimizations are tricky.

In the end, the real winner is white*0, but... that won't work in opaque ARGB colors, where A is 255.