Anti-aliased image clipping

Question

I could really use some help with this.. I am completely stuck!
I want to take a square BufferedImage (created from a jpeg)
and clip it with an inscribed circle, such that only a circular image
cutout remains (and the exterior of the circle is transparent).
However, I need to do this with anti-aliasing so that the edge of the
circle is smooth.
I have tried the following two methods, but neither one produces
the correct result:
//simply returns the original image
private static BufferedImage cutoutCircle(BufferedImage img, int w, int h) {
Graphics2D g2d = img.createGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
Shape circle = new java.awt.geom.Ellipse2D.Double(0,0,w,h);
g2d.setClip(circle);
return img;
//cuts out circle but not anti-aliased
private static BufferedImage cutoutCircle(BufferedImage orig, int w, int h) {
BufferedImage bimg = new BufferedImage(w, h,
BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = bimg.createGraphics(); //this is blank (transparent)
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
Shape circle = new java.awt.geom.Ellipse2D.Double(0,0,w,h);
g2d.setClip(circle);
g2d.drawImage(orig, 0, 0, null);
return bimg;
}

Answer 1

At least try to run this code, and then maybe you'll start trying to think about what I said.
import javax.imageio.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.image.*;
import java.awt.geom.*;
public class UseYourBrain extends JPanel implements MouseMotionListener, MouseListener {
     private BufferedImage image = null;
     private double radius = 100;
     private Area area = null;
     private Color antialiasColor = Color.black;
     public UseYourBrain(BufferedImage img) {
          super();
          image = img;
          addMouseListener(this);
          addMouseMotionListener(this);
     public void mousePressed(MouseEvent evt) {
          setArea(evt.getX(), evt.getY());
          repaint();
     public void mouseReleased(MouseEvent evt) {}
     public void mouseClicked(MouseEvent evt) {}
     public void mouseEntered(MouseEvent evt) {}
     public void mouseExited(MouseEvent evt) {}
     public void mouseDragged(MouseEvent evt) {
          setArea(evt.getX(), evt.getY());
          repaint();
     public void mouseMoved(MouseEvent evt) {}
     private void setArea(int x, int y) {
          int w = image.getWidth();
          int h = image.getHeight();
          area = new Area(new Rectangle(0, 0, w, h));
          area.subtract(new Area(new Ellipse2D.Double(x, y, radius, radius)));
     public void paint(Graphics _g) {
          super.paint(_g);
          Graphics2D g = (Graphics2D) _g;
          g.drawImage(image, 0, 0, this);
          if (area != null) {
               g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
               g.setColor(antialiasColor);
               g.fill(area);
     public static void main(String[] args) throws Throwable {
          if (args.length == 0) {
               System.out.println("Usage: UseYourBrain <filename>");
               System.exit(0);
          JFrame f = new JFrame();
          BufferedImage img = ImageIO.read(new java.io.File(args[0]));
          JPanel p = new UseYourBrain(img);
          f.setContentPane(p);
          f.setSize(500, 500);
          f.show();
          f.addWindowListener(new WindowAdapter() {
               public void windowClosing(WindowEvent evt) {
                    System.exit(0);
}