import java.awt.Color;

    protected Color[] grayLevels() {
        Color[] grayLevels = new Color[256];

        for (int i = 0; i < 256; i++)
            grayLevels[i] = new Color(i, i, i);

        return grayLevels;
    }

    public Color[][] filter(Color[][] inPixels, String parameter) {
        int height = inPixels.length;
        int width  = inPixels[0].length;

        short[][] inIntensity = computeIntensity(inPixels);
        Color[][] outPixels   = new Color[height][width];
        Color[]   grayLevels  = grayLevels();

        for (int i = 0; i < height; ++i)
            for (int j = 0; j < width; ++j)
                outPixels[i][j] = grayLevels[inIntensity[i][j]];

        return outPixels;
    }