Changing colors in an Image object

Question

I have an Image objects and want all the red pixels in it changed to blue during runtime.
How can I do that?

Answer 1

ImageIcon oldImage = new ImageIcon("C:\\duke\\t1.gif");
ImageProducer producer = new FilteredImageSource(oldImage.getImage().getSource(),new MyFilter());
ImageIcon newImage = new ImageIcon(Toolkit.getDefaultToolkit().createImage(producer));
JLabel jl = new JLabel(newImage);
// Image filter
class MyFilter extends RGBImageFilter{
  public int filterRGB(int x, int y, int rgb) {
    int alpha = (rgb >> 24) & 0xff;
    int red = (rgb >> 16) & 0xff;
    int green = (rgb >> 8) & 0xff;
    int blue = rgb & 0xff + red;
    if (blue>255) blue=255;
    red=0;
    return alpha << 24 | red << 16 | green << 8 | blue << 0;
}