image processing in java

public class testing
{
static BufferedImage image;
public static void main(String[] args) throws IOException {

ArrayList<Integer> l1=new ArrayList<Integer>();
ArrayList<Integer> l2=new ArrayList<Integer>();
ArrayList<Integer> l3=new ArrayList<Integer>();

image = ImageIO.read(new File("nn33.png"));
int w = image.getWidth();
int h = image.getHeight();
for (int y = 0; y < h; y++)
{
for (int x = 0; x < w; x++)
{
Color c = new Color(image.getRGB(x, y));
int A=c.getRed()+3;
l1.add(A);
int B=c.getBlue()+2;
l2.add(B);
int C=c.getGreen();
l3.add(C);

}
}
i will write above code but i write image again by using different color values how can i write