Resize BufferedImage of a Transparent GIF PNG JPG

Question

i must be losing my mind.
i use this same code in another program and it works fine.
first the images were transparent PNGs but then i changed
them to non-transparent GIFs and then JPGs.
no errors are thrown - but the images are being drawn at
their original size.
ive tried 3 different resizing methods and none work.
why doesnt this code work:
BufferedImage wp = ImageIO.read(new File("" + dir + "wp.gif"));
resize(wp);
public void resize(BufferedImage bi){
  AffineTransform tx = new AffineTransform();
     double xsc = ( sx ) / ( (double) bi.getWidth() );
     double ysc = ( sy ) / ( (double) bi.getHeight() );
    tx.scale(xsc, ysc);
    AffineTransformOp op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
    bi = op.filter(bi, null);
}

Answer 1

public void resize(BufferedImage bi){
    bi = op.filter(bi, null);
}The variable in your "resize" method is a local variable. Reassigning a value to it does not change anything outside the method. You will have to return the new value of "bi" or reassign the instance variable to the filtered image:
    wp = op.filter(bi, null);
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.*;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
public class ImageSizing
    BufferedImage orig;
    public ImageSizing(BufferedImage image)
        orig = image;
    private BufferedImage scale(BufferedImage bi)
        AffineTransform tx = new AffineTransform();
        tx.scale(0.80, 0.80);
        AffineTransformOp op = new AffineTransformOp(tx,
                                         AffineTransformOp.TYPE_BICUBIC);
        return op.filter(bi, null);
    private JPanel getPanel()
        JPanel panel = new JPanel(new GridLayout(1,0));
        panel.add(new JLabel(new ImageIcon(orig), JLabel.CENTER));
        panel.add(new JLabel(new ImageIcon(scale(orig)), JLabel.CENTER));
        return panel;
    public static void main(String[] args) throws IOException
        String path = "images/bclynx.jpg";
        BufferedImage bi = ImageIO.read(ImageSizing.class.getResource(path));
        ImageSizing test = new ImageSizing(bi);
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(test.getPanel());
        f.pack();
        f.setLocation(200,200);
        f.setVisible(true);
}