public int[] directWavelet(int c[], int h) {
        int result[] = new int[h * h];
        for (int i = 0; i < (h * h) / 2; i++) {
            result[2 * i] = ((c[2 * i] + c[2 * i + 1]));
            result[2 * i + 1] = ((c[2 * i] - c[2 * i + 1]));
        }
        return result;
    }