How to fix the blurry image when I run my java swing project

Question

I currently studying the java swing builder as a new tech skills. I need to study how to import the image on my canvas. Yes it successfully imported and the image clearly define and not blurry. however when I run the project the image that I import to the project it goes blurry. I don't know why it happens. I research some functionality like get scaled but nothing happens it goes same output it get blurry.

Image Dimension: 250x250

Here is my code that I implement on my project:

private Image doctor_ppe = new ImageIcon(LoginScreen.class.getResource("/assets/large.png")).getImage().getScaledInstance(250, 250, Image.SCALE_SMOOTH);


JLabel lblDds = new JLabel("");
    lblDds.setVerticalAlignment(SwingConstants.BOTTOM);
    lblDds.setHorizontalAlignment(SwingConstants.CENTER);
    lblDds.setIcon(new ImageIcon(doctor_ppe));
    lblDds.setBounds(59, 305, 236, 251);
    panel.add(lblDds);

Difference of not runnable project and runnable project:

Image not blurry:

Image Blurry After I run the project:

Hope someone experience this, hope will help on my problem thank you.

Answer 1

however when I run the project the image that I import to the project it goes blurry.

Probably because your desktop is using a scaling factor greater than 1.0, so the image is upscaled when it is painted.

If you want to change the scaling for the entire application you can try:

1. using the command line -Dsun.java2d.uiScale=1.0, or
2. set it programmatically using System.setProperty("sun.java2d.uiScale", "1.0")

Another option might be to prevent only the Icon from scaling:

import java.awt.*;
import java.awt.geom.AffineTransform;
import javax.swing.*;


public class NoScalingIcon implements Icon
{
    private Icon icon;

    public NoScalingIcon(Icon icon)
    {
        this.icon = icon;
    }

    public int getIconWidth()
    {
        return icon.getIconWidth();
    }

    public int getIconHeight()
    {
        return icon.getIconHeight();
    }

    public void paintIcon(Component c, Graphics g, int x, int y)
    {
        Graphics2D g2d = (Graphics2D)g.create();

        AffineTransform at = g2d.getTransform();

        int scaleX = (int)(x * at.getScaleX());
        int scaleY = (int)(y * at.getScaleY());

        int offsetX = (int)(icon.getIconWidth() * (at.getScaleX() - 1) / 2);
        int offsetY = (int)(icon.getIconHeight() * (at.getScaleY() - 1) / 2);

        int locationX = scaleX + offsetX;
        int locationY = scaleY + offsetY;

        //  Reset scaling to 1.0 by concatenating an inverse scale transfom

        AffineTransform scaled = AffineTransform.getScaleInstance(1.0 / at.getScaleX(), 1.0 / at.getScaleY());
        at.concatenate( scaled );
        g2d.setTransform( at );

        icon.paintIcon(c, g2d, locationX, locationY);

        g2d.dispose();
    }

    public static void main(String[] args)
    {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }

    public static void createAndShowGUI()
    {
        JButton button = new JButton( "Button" );
        NoScalingIcon icon = new NoScalingIcon( new ImageIcon("box.jpg") );
        button.setIcon( icon );

        JPanel panel = new JPanel( );
        panel.add( button );

        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(panel);
        f.setSize(200, 200);
        f.setLocationRelativeTo( null );
        f.setVisible(true);
    }
}