Help contrast stretch

Hi all,
How to apply a simple contrast stretch algorithm on grayscale Image?
Image inImage = new ImageIcon(f.getAbsolutePath(), f.getName()).getImage();
          int maxDim = 110;
                double scale = (double) maxDim / (double) inImage.getHeight(null);
                if (inImage.getWidth(null) > inImage.getHeight(null))
                    scale = (double) maxDim / (double) inImage.getWidth(null);
                int scaledW = (int) (scale * inImage.getWidth(null));
          int scaledH = (int) (scale * inImage.getHeight(null));
                Image img = inImage.getScaledInstance(scaledW , scaledH, Image.SCALE_SMOOTH);
                //Grayscale images
                Image filtered = Toolkit.getDefaultToolkit().createImage(new FilteredImageSource(img.getSource(), new GrayscaleImageFilter()));
                //Converto tipo Image in PlanarImage
                ParameterBlock pd = new ParameterBlock();
                pd.add(img);
                PlanarImage img_original = JAI.create("awtImage", pd);
                ParameterBlock pb = new ParameterBlock();
                pb.add(filtered);
                PlanarImage img_gray = JAI.create("awtImage", pb);
                ParameterBlock pbMaxMin = new ParameterBlock();
                pbMaxMin.addSource(img_gray);
                RenderedOp extremaOp = JAI.create("extrema", pbMaxMin);
                // Get the extrema of all bands !
                double[] allMins = (double[])extremaOp.getProperty("minimum");
                double[] allMaxs = (double[])extremaOp.getProperty("maximum");
                for(int b=0;b<allMins.length;b++)
                System.out.println("Band "+b+" values are between "+allMins[b]+" and "+allMaxs);
//BufferedImage myBufImg = img_gray.getAsBufferedImage();
// CONTRAST STRETCH ?????
DisplayJAI original_image = null;
original_image = new DisplayJAI(img_original);
jToolBar1.add(original_image);
jToolBar1.revalidate();
DisplayJAI gray_image = null;
gray_image = new DisplayJAI(img_gray);
jToolBar3.add(gray_image);
jToolBar3.revalidate();

Thank you very much! That's exactly what I was looking for.
Best,

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Thank you very much! That's exactly what I was looking for.
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Message was edited by: David Bogie Chq-1

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