Loss of PNG Image Quality

Question

I'm trying to display a PNG as a title screen for a game. I'm quite the newb, as the image itself will attest.
Source: http://i30.tinypic.com/sfw96o.png
Screenshot result: http://i25.tinypic.com/29m2d6v.png
I've got all the RenderingHints turned to the quality settings, and use the following image loading/drawing code to put the freshly loaded image into a BufferedImage for later use:
g2.drawImage((new ImageIcon(getClass().getClassLoader().getResource("assets/title.png"))).getImage(),0,0,null);Any ideas? I'm hoping that this is something that people have seen before, but I'm happy to provide more code upon request.

Answer 1

>
Thanks for the reply again. Since Numain's example causes the same loss of color depth on my machine, I've just modified it:>Huh...
OK - I tried your source, and like Numain, failed to see the problem on my PC - the image appeared in the frame at the full color depth.
There were some slightly suspicious aspects to that source, so I have changed them, and made a few other changes to get more information. Run the source below and post back your results, but most importantly, does the problem still happen using this source?
Here are my results..
java.vm.version:      1.6.0-b105
java.vendor:      Sun Microsystems Inc.
os.name:      Windows XP
os.arch:      x86
os.version:      5.1
*** end system props
GraphicsEnvironment: sun.awt.Win32GraphicsEnvironment@9f671b
GraphicsDevice: Win32GraphicsDevice[screen=0]
GraphicsConfiguration: sun.awt.Win32GraphicsConfig@1b9240e
  [dev=Win32GraphicsDevice[screen=0],pixfmt=0]
DisplayMode - bitdepth/WxH: 24/1024x768
ColorModel (screen): ColorModel: #pixelBits = 24 numComponents = 3
  color space = java.awt.color.ICC_ColorSpace@ca0115
  transparency = 1 has alpha = false isAlphaPre = false
*** end screen props
Read start:      Sat Mar 22 20:11:51 EST 2008
Read end:      Sat Mar 22 20:17:04 EST 2008
*** end image load
ColorModel: ColorModel: #pixelBits = 32 numComponents = 4
  color space = java.awt.color.ICC_ColorSpace@ca0115
  transparency = 3 has alpha = true isAlphaPre = false
true is Error? false
*** end cons..:      Sat Mar 22 20:17:04 EST 2008The code used.
import java.awt.*;
import java.awt.image.*;
import javax.swing.*;
import javax.imageio.ImageIO;
import java.net.URL;
import java.util.Date;
public class PngQuality extends JPanel {
  private BufferedImage image;
  public PngQuality() throws Exception {
    URL imageUrl = new URL("http://i30.tinypic.com/sfw96o.png");
    GraphicsEnvironment ge = GraphicsEnvironment.
      getLocalGraphicsEnvironment();
    System.out.println( "GraphicsEnvironment: " + ge );
    GraphicsDevice gd = ge.getDefaultScreenDevice();
    System.out.println("GraphicsDevice: " + gd);
    GraphicsConfiguration gc = gd.getDefaultConfiguration();
    System.out.println("GraphicsConfiguration: " + gc);
    DisplayMode dm = gd.getDisplayMode();
    System.out.println("DisplayMode - bitdepth/WxH: " +
      dm.getBitDepth() + "/" +
      dm.getWidth() + "x" +
      dm.getHeight()
    ColorModel cmScreen = gc.getColorModel();
    System.out.println("ColorModel (screen): " + cmScreen);
    System.out.println("*** end screen props");
    // read the image..
    System.out.println("Read start: \t" + new Date() );
    image = ImageIO.read(imageUrl);
    System.out.println("Read end: \t" + new Date() );
    System.out.println("*** end image load");
    setPreferredSize(new Dimension(800, 600));
    MediaTracker tracker = new MediaTracker(this);
    tracker.addImage(image, 0);
    /* Thought it might be useful.. */
    String[] properties = image.getPropertyNames();
    if (properties!=null) {
      for (int ii=0; ii<properties.length; ii++) {
        System.out.println(
          properties[ii] +
          ": " +
          image.getProperty( properties[ii] )
    /* Check the color model.. */
    ColorModel cm = image.getColorModel();
    System.out.println("ColorModel: " + cm);
    // I get the impression that ImageIO.read blocks and
    // this is redundant, but keep for the moment.
    try {
      tracker.waitForAll();
    } catch(InterruptedException ie) {
      ie.printStackTrace();
    // Is there any error loading the image, in that VM?
    System.out.println("" + tracker.checkAll() +
      " is Error? " + tracker.isErrorAny()
    System.out.println("*** end cons..: \t" + new Date() );
  protected void paintComponent(Graphics g) {
    // did you not read my advice about the ImageObserver?
    // What am I ..talkin' to myself here?
    g.drawImage(image, 0, 0, this);
  public static void main(String[] args) {
    /* Get some basic info. */
    String[] sysProp = {
      "java.vm.version",
      "java.vendor",
      "os.name",
      "os.arch",
      "os.version"
    for (int ii=0; ii<sysProp.length; ii++) {
      System.out.println( sysProp[ii] +
        ": \t" +
        System.getProperty(sysProp[ii]) );
    System.out.println("*** end system props");
    // best to invoke a runnable to create the GUI
    Runnable r = new Runnable() {
      public void run() {
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        try {
          f.getContentPane().add(new PngQuality());
        } catch(Exception e) {
          f.getContentPane().add(
            new JLabel("See Stacktrace!"));
          e.printStackTrace();
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    EventQueue.invokeLater(r);
}Oh, and AFAIR is a less common variant of AFAIK. As Far As I Recall/As Far As I Remember.
My apologies for tossing about obscure abbreviations.
There was a thread on usenet I vaguely recall where some nonser wished to implement a JProgressBar for an image download. Everyone pointed out that images properly displayed within a Java based ImageObserver would provide a better (+ prettier and more relevant) download indicator. GIF images will (or at least, can) show 'low detail' before full download. JPEG will scan down from the top to the bottom of an image. Someone pointed out that PNG supports (I think it was) a number of different mechanisms for 'quick low-detail display'.
Oddly, this is one of the few instances I've seen where the (apparently) blocking behavior of the ImageIO.read() calls for a JPB/ProgressMonitorInputStream.
Edit 1:
ColorModel and GraphicsConfiguration info. line wrapped for better formatting.
P.S. Can you tell from my output, why I commented on the image size? ;-)
Edited by: AndrewThompson64 on Mar 22, 2008 9:46 AM