A mini benchmark to test if Java compatible images are rendered faster than images loaded in the default manner, results printed on the command line.

CompatibleImageBenchMark.java

import java.awt.Color;
import java.awt.Graphics;
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.Image;
import java.awt.Transparency;
import java.awt.image.BufferedImage;

import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class CompatibleImageBenchMark extends JPanel implements Runnable
{
  public static void main(String[] args)
  {
    SwingUtilities.invokeLater(new CompatibleImageBenchMark());
  } 

  Image optimal, suboptimal;

  public void run()
  {
    try
    {
      optimal = createCompatibeImage();

      suboptimal = createSuboptimalImage();
    }
    catch (Exception e)
    {
      e.printStackTrace();
    }

    JFrame frame;   

    frame = new JFrame("Compatible image benchmark");
    frame.setSize(800, 600);
    frame.setContentPane(this);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
  } 

  @Override
  protected void paintComponent(Graphics g)
  {
    super.paintComponent(g);   

    long start, elapsed;   

    start = System.currentTimeMillis();

    for (int i = 0; i < 10; i++)
    {
      g.drawImage(suboptimal, 10, 10, null);
    }
    elapsed = System.currentTimeMillis() - start;   

    System.out.println("elapsed for suboptimal image is " + elapsed + "ms");

    start = System.currentTimeMillis();

    for (int i = 0; i < 10; i++)
    {
      g.drawImage(optimal, 10, 10, null);
    }

    elapsed = System.currentTimeMillis() - start;

    System.out.println("elapsed for optimal image is " + elapsed + "ms");
  }

  private BufferedImage createCompatibeImage() throws IOException
  {
    BufferedImage suboptimalImage = createSuboptimalImage(Color.GREEN);   
    GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
    GraphicsDevice gs = ge.getDefaultScreenDevice();
    GraphicsConfiguration gc = gs.getDefaultConfiguration();    

    // Create an image that does not support transparency
    BufferedImage image = gc.createCompatibleImage(
      suboptimalImage.getWidth(), suboptimalImage.getHeight(), Transparency.TRANSLUCENT
    );

    Graphics g;   

    g = image.getGraphics();
    g.drawImage(suboptimalImage, 0, 0, null);

    return image;
  }

  private BufferedImage createSuboptimalImage() throws IOException
  {
    BufferedImage suboptimalImage = ImageIO.read(new File("my image.png"));

    return suboptimalImage;
  }
}