Convert image from color to black&white

Question

Hi,
I'd like to transform a colored picture (from a gif or jpeg file for
exemple) in a Black and White image (wbmp format). I use a
ColorConvertOp to do that, but I don't know how to param it to have a nice
conversion, not a pixel level conversion. Here is the code I used:
BufferedImage bi4 = new BufferedImage(bi3.getWidth(), bi3.getHeight(),
BufferedImage.TYPE_BYTE_BINARY);
ColorConvertOp cco2 = new
ColorConvertOp(ColorSpace.getInstance(ColorSpace.CS_GRAY), null);
cco2.filter(bi3, bi4);
Where bi3 is my original BufferedImage.
Do you know where I can find more information on this conversion, because in
the help I don't understand everything (I have no knowledge on picture
conversion)?
Thanks for all
Vincent

Answer 1

Try this example
regards
Stas
import javax.swing.*;
import java.awt.*;
import java.awt.image.*;
import java.io.*;
public class Test {
JScrollPane scroll;
JEditorPane edit=new JEditorPane();
public Test() throws Exception {
JFrame frame=new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
BufferedImage sourceImage=new BufferedImage(100,100,BufferedImage.TYPE_INT_RGB);
Graphics g=sourceImage.getGraphics();
g.setColor(Color.red);
g.fillRect(0,0,100,100);
g.setColor(Color.blue);
g.fillRect(10,10,80,80);
g.setColor(Color.yellow);
g.fillRect(20,20,60,60);
g.setColor(Color.white);
g.drawString("test",5,15);
frame.getContentPane().add(new JLabel(new ImageIcon(sourceImage)));
BufferedImage grayImage=new BufferedImage(100,100,BufferedImage.TYPE_BYTE_GRAY);
grayImage.getGraphics().drawImage(sourceImage,0,0,null);
frame.getContentPane().add(new JLabel(new ImageIcon(grayImage)),BorderLayout.SOUTH);
frame.pack();
frame.setLocationRelativeTo(null);
frame.show();
public static void main(String[] args) throws Exception {
new Test();