slowClip.java

//How to create a BufferedImage from a sub rectangle of another BufferedImage, a.k.a. 'clipping'.

BufferedImage src = ImageIO.read(new File("SomeFile.png"));

Rectangle clip = new Rectangle((src.getWidth() - 200) / 2, (src.getHeight() - 200) / 2, 200, 200);

BufferedImage ret = new BufferedImage(clip.width, clip.height, image.getType());

//short but slow clip and paste :
ret.getRaster().setRect(-clip.x, -clip.y,  image.getData(clip));
//done !