java code not exporting buffered Image in correct size

Question

My java code below's goal is to export a image in a 400 X 400 format. Right now the code does export a image. However it exports the image in its original size. I don't know why it does not export in its desired format. There are no errors present. The goal is just to some how get line

BufferedImage scaledButtonImage = new BufferedImage(400, 400, bimg.getType());

to work in its way.

import java.awt.BorderLayout;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class ren {
    Frame f;
    JLabel b2 = new JLabel("");

    ren() throws IOException {
        f = new JFrame();
        b2.setIcon(new ImageIcon("/Users/johnzalubski/Desktop/dropIn/Complete-Audi-Buying-Guide-gear-patrol-lead-full.jpg"));

        JButton b3 = new JButton("Exported");

        File file = new File("aa.png");

        f.add(b2, BorderLayout.CENTER);
        f.add(b3, BorderLayout.SOUTH);

        f.setSize(400, 500);
        f.setVisible(true);

        b3.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                Icon ico = b2.getIcon();
                // Create a buffered image
                BufferedImage bimg = new BufferedImage(ico.getIconWidth(), ico.getIconHeight(),
                        BufferedImage.TYPE_INT_RGB);
                // Create the graphics context
                Graphics g = bimg.createGraphics();
                // Now paint the icon
                ico.paintIcon(null, g, 0, 0);
                g.dispose();

                BufferedImage scaledButtonImage =
                        new BufferedImage(400, 400, bimg.getType());
                Graphics g1 = scaledButtonImage.createGraphics();
                g1.drawImage(scaledButtonImage, 0, 0, 400, 400, null);
                //                  
                g1.dispose();

                b2.setIcon(new ImageIcon(bimg));
                try {
                    ImageIO.write(bimg, "png", file);
                } catch (IOException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }
            }
        });
    }

    public static void main(String[] args) throws IOException {
        new ren();
    }
}

Answer 1

If you want to create a scaled version of bimg in scaledButtonImage then this line:

g1.drawImage(scaledButtonImage, 0, 0, 400, 400, null);

should be:

g1.drawImage(bimg, 0, 0, scaledButtonImage.getWidth(), scaledButtonImage.getHeight(),
                   0, 0, bimg.getWidth(), bimg.getHeight() null);

Currently your code is drawing scaledButtonImage into itself. Also, if you want to get a scaled copy of bimg you have to use the version of drawImage that lets you specifiy the destination and source rectangles.

Finally, you need to write out the scaledButtonImage, not bimg. Change this line

ImageIO.write(bimg, "png",file);

to

ImageIO.write(scaledButtonImage, "png",file);