BufferedImage.TYPE_INT_ARGB is producing a black background

[chaitanya karthikk]

Hi everybody, I am trying to create a jpeg file and then write text on to it. When I try to create a jpeg file with BufferedImage.TYPE_INT_ARGB it is producing a black background instead on white, they said BufferedImage.TYPE_INT_RGB will produce black and BufferedImage.TYPE_INT_ARGB will produce white backgrounds, but its not happening in this case, please tell me what I have done wrong and please tell me the difference between those both.

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.awt.Color;
import java.awt.Graphics2D;
class ImageCreator
{
	public static void main(String kk[])
	{
		BufferedImage bImage=new BufferedImage(100,100,BufferedImage.TYPE_INT_ARGB);
		try
		{
			//for(byte i=10;i<91;i++)
				//bImage.setRGB(i,10,0xffffff);
			ImageIO.write(bImage,"JPG",new File("karthik.jpg"));
			
		}
		catch(Exception e)
		{
			System.out.println("cannot create the file");
			e.printStackTrace();
		}
	}
}

Thank you all in advance, have a good day.

[Rob Spoor]

Who is "they" that said the background would be black/white?

If you need the background to be white, just paint the entire image white before you do anything else:

Graphics2D g = bImage.createGraphics();
g.setColor(Color.WHITE);
g.fillRect(0, 0, bImage.getWidth(), bImage.getHeight());
// draw other things on g
g.dispose();

[Jesper de Jong]

I'm not sure why that happens; it might be because the program that you are using to display the JPEG does not show what parts of the image are transparent. If you use TYPE_INT_ARGB, there will be four channels in the image: red, green, blue and alpha; the latter determines the transparency of each pixel.

Before writing the text on the BufferedImage, it's better to fill the whole image with a certain color, by drawing a rectangle that fills the whole image. For example (note, untested code):

BufferedImage bImage = new BufferedImage(100,100,BufferedImage.TYPE_INT_ARGB);

Graphics2D g = (Graphics2D) bImage.getGraphics();

// Clear the background with white
g.setBackground(Color.WHITE);
g.clearRect(0, 0, 100, 100);

// Write some text
g.setColor(Color.BLACK);
g.drawString(20, 20, "Hello");

g.dispose();

[chaitanya karthikk]

Hi @Jesper @Rob Prime

the problem has been solved, actually in the image it is showing black background, when I try to read the image and display it I am unable to see any background, when I tried the same with TYPE_INT_RGB I am able to see the background.