Can't get RescaleOp to retain transparancy (it sets alpha to black)

Question

Got my code here, the operation fills in the transparancy with black:
public static BufferedImage brighten(BufferedImage bi) {
            RenderingHints hints = new RenderingHints(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY);
         RescaleOp op = new RescaleOp(scaleFactor, 0, hints);
         BufferedImage copy = op.createCompatibleDestImage(bi, bi.getColorModel());
         op.filter(bi, copy);
         return copy;
}Ive looked on the web, but i only found one reference to this here - http://forums.sun.com/thread.jspa?threadID=568146 - , and I tried doing what solved it for them (as far as i can tell setting the source and destination to the same thing) but that didn't work - any help would be much appreciated!
Joe
Edited by: 794057 on 27-Oct-2010 06:36
for some reason links arnt working
Edited by: 794057 on 27-Oct-2010 06:38
actually they are - just not if you use the "link" button! crazy

Answer 1

I think I was passing it an incorrect image, but now i get an empty image:
        public static ImageIcon changeBrightnessContrast(Icon icon, float brighness, float contrast)
          ImageIcon ret = new ImageIcon();
          BufferedImage image = (BufferedImage) iconToImage(icon);
          BufferedImage imagecopy = copy(image, BufferedImage.TYPE_INT_RGB);
        image = brighten(imagecopy);
        ret.setImage(image);
          return ret;
        public static BufferedImage copy(BufferedImage bi, int type) {
          BufferedImage result = new BufferedImage(bi.getWidth(), bi.getHeight(), type);
          Graphics2D g = result.createGraphics();
          g.drawRenderedImage(bi, null);
          g.dispose();
          return result;
        public static BufferedImage brighten(BufferedImage bi) {
          float scaleFactor = 1.2f;
          //RenderingHints hints = new RenderingHints(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY);
          RescaleOp op = new RescaleOp(scaleFactor, 0, null);
          BufferedImage copy = op.createCompatibleDestImage(bi, bi.getColorModel());
          op.filter(bi, copy);
          return copy;
     }here is how I use it, the above code set transparancy to black (understandably, as the image its copying to has no alpha channel) however, if i set it to have one:
BufferedImage imagecopy = copy(image, BufferedImage.TYPE_INT_ARGB);
the image I get not is not there! (or all transparent??)
Edited by: 794057 on 27-Oct-2010 06:58
for some reason chanel is ***** out C H A N E L (as a misspelled channel)
Edited by: 794057 on 27-Oct-2010 07:01