Problem with creating a BufferedImage and save it as bmp file

[Thomas Houseman]

Hi,
I'm trying to create a BufferedImage, add a text to it , and save it as a bmp picture.
But, the picture file created with size 0 and it's actually empty file (but it created).
This is the code :

  
import java.util.Scanner;
import java.awt.image.BufferedImage;
import java.awt.Color;
import javax.imageio.ImageIO;

public class TextToPic {
   public static void main(String[] args) {
      BufferedImage image = new BufferedImage(200,300, BufferedImage.TYPE_INT_RGB);
      image.getGraphics().setColor(Color.black);
      image.getGraphics().drawString("Hello this is a text",20,20);
      ImageIO.write(image,".bmp",new File("MyImage.bmp"));
   }

}

  

What am I doing wrong ?!

Thanks !

[Ernest Friedman-Hill]

Well, the format name should be "BMP", not ".bmp", so you might give that a try. Otherwise, it's probably OK (except that you might be writing a white string on a white background, not sure.)

[Thomas Houseman]

Hi.
It was actually black in the code, i fixed it.
Yet it doesn't work. A file has been created but with size 0.
Can anyone help please ? What am i doing wrong in the code ?

[pete stein]

Does your BufferedImage constructor call compile? Don't you need to add the type of image you want to create? BufferedImage has constants that are used for this sort of thing, such as BufferedImage.TYPE_INT_RGB

for instance,

import java.awt.image.BufferedImage;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JOptionPane;

public class TextToPic {
   private static final String IMAGE_FILE = "MyImage.bmp";
   private static final int WIDTH = 200;
   private static final int HEIGHT = 300;

   public static void main(String[] args) throws IOException {
      BufferedImage image = new BufferedImage(WIDTH, HEIGHT, 
               BufferedImage.TYPE_INT_RGB);
      Graphics g = image.getGraphics();
      g.setColor(Color.white);
      g.fillRect(0, 0, WIDTH, HEIGHT);
      g.setColor(Color.black);
      g.drawString("Hello this is a text", 20, 20);
      ImageIO.write(image, "BMP", new File(IMAGE_FILE));
      g.dispose();
      
      Image image2 = ImageIO.read(new File(IMAGE_FILE));
      JLabel label = new JLabel(new ImageIcon(image2));
      JOptionPane.showMessageDialog(null, label);
   }

}

corrected the getting multiple Graphics objects

[Thomas Houseman]

pete stein wrote:Does your BufferedImage constructor call compile? Don't you need to add the type of image you want to create? BufferedImage has constants that are used for this sort of thing, such as BufferedImage.TYPE_INT_RGB

Sorry, I added it to the original code, YET it doesn't work.
H-E-L-P Please

[pete stein]

Thomas Houseman wrote:Sorry, I added it to the original code, YET it doesn't work.

Calm down, it'll be alright. Please see corrections to code above.

[Thomas Houseman]

Thank You so much pete stein !
I will try that soon and let you know if it worked for me.

bye

[Rob Spoor]

I took your original code, fixed the imports, added a throws clause, compiled it and ran it. It gave me a 0 byte BMP file. Then I changed ".bmp" into "bmp" (as Ernest already suggested), compiled it and ran it. It gave me a 180,054 byte BMP file, with a black background and white letters.

When you call getGraphics(), it creates a new Graphics object. As such, your second call created a second Graphics object, that did not have the black color set. When drawing on a BufferedImage, you should do that as follows:

// getGraphics calls createGraphics, so call it directly to get a more specific Graphics2D reference
Graphics2D g2d = image.createGraphics();
g2d.setColor(Color.black);
g2d.drawString("Hello this is a text",20,20);
g2d.dispose(); // don't forget to clean up!

This gives me an all-black image. Sure, it has the text printed, but in black

[Thomas Houseman]

Thank you all , now it works.
Probably the "BMP" instead of ".bmp" solved it.
Have a great day.