Putting text in an image file

[Ishan Bhatt]

Hi!
How can we put some text in an image file using Java?
I have a String and I want to put this String in an image file (.gif, .bmp, .jpg or any other).
Any help would be appreciated.

Thank you.
Ishan

[Peter Chase]

You certainly can write text into an image in Java, and you can write the result into a file in some popular image formats.

However, if, as posting in the beginner forum suggests, you are new to Java, this might not be a good choice for your first Java program!

You can use javax.imageio.ImageIO class to read and write the image.

To write text into the image, you need to get it as a BufferedImage. Then get a Graphics2D from your BufferedImage. Then you can use Graphics2D.drawString() to write text. You may wish to set the Font and Color of the Graphics2D before writing the text. A FontMetrics object can be used to find out how big the text will be.

[Jeff Albertson]

I agree that this may not be the best topic for a beginner to cut his teeth on, but here's Sun's tutorial: http://java.sun.com/docs/books/tutorial/2d/index.html

And here's the Hello World program:

import java.awt.*;
import java.awt.font.*;
import java.awt.geom.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;
 
public class HelloWorld {
public static void main(String[] args) throws IOException {
File file = new File("temp.jpeg");
String message = "Hello, world!";
Font font = new Font("serif", Font.PLAIN, 96);
boolean antialising = true;
boolean fractionalMetrics = true;
 
Object antialisingHint = antialising ?
RenderingHints.VALUE_TEXT_ANTIALIAS_ON : RenderingHints.VALUE_TEXT_ANTIALIAS_OFF;
Object fractionalMetricsHint = fractionalMetrics ?
RenderingHints.VALUE_FRACTIONALMETRICS_ON : RenderingHints.VALUE_FRACTIONALMETRICS_OFF;
FontRenderContext frc = new FontRenderContext(null, antialising, fractionalMetrics);
Rectangle2D bounds = font.getStringBounds(message, frc);
int width = (int) Math.ceil(bounds.getWidth());
int height = (int) Math.ceil(bounds.getHeight());
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, antialisingHint);
g.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, fractionalMetricsHint);
g.setColor(Color.WHITE);
g.fillRect(0, 0, width, height);
g.setColor(Color.BLUE);
g.setFont(font);
g.drawString(message, (float)-bounds.getX(), (float)-bounds.getY());
g.dispose();
ImageIO.write(image, "jpeg", file);
 
}
}

[ February 02, 2006: Message edited by: Jeff Albertson ]