Accord.Math.Transforms.FourierTransform2.HighestOneBit C# (CSharp) Method

        private static int HighestOneBit(int i)
        {
            i |= (i >> 1);
            i |= (i >> 2);
            i |= (i >> 4);
            i |= (i >> 8);
            i |= (i >> 16);
            return i - (int)((uint)i >> 1);
        }