Create sparse BufferedImage in java

Question

I need to create an image with a very high resolution, but the image is relatively "sparse", I need to draw only some areas of the image.

For example, using the following code

/* this take 5GB memory */

    final BufferedImage img = new BufferedImage( 36000, 36000, BufferedImage.TYPE_INT_ARGB);

/* draw something */

    Graphics g = img.getGraphics();
    g.drawImage(....);

/* output as PNG */

    final File out = new File("out.png"); 
    ImageIO.write(img, "png", out); 

The PNG image at the end that I created is ONLY about 200 ~ 300 MB.

Question: How can I avoid creating a 5GB BufferedImage at the beginning? I need an image with a large size, but with very rare color information.

Is there any thread for BufferedImage so it doesn't take up so much memory?

Answer 1

- , BufferedImages?

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Answer 2

TYPE_INT_ARGB , 4 . , .

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