Convert a region of a JPanel into a BufferedImage

Question

Hi,

I need to convert a certain region of an jpanel into a bufferedImage, or other format to be shown in another jpanel.

By now, I only saw codes that converts the whole jpanel into a bufferedImage, but in my case, I need just an area inside an jpanel.

thanks

Answer 1

The easiest would probably be Robot.createScreenCapture()

You'll need to translate from the panel's coordinate system to the screen coordinate system. See Component.getBounds() and Component.getLocationOnScreen().

Answer 2

By now, I only saw codes that converts the whole jpanel into a bufferedImage, but in my case, I need just an area inside an jpanel.

Then take that image and repaint the desired area into a new image and you're done.

Answer 3

Since you already have code to convert the entire thing to a BufferedImage, you can use that, then call getSubImage on the resulting BufferedImage to get a subregion.

Answer 4

create a BufferedImage with the requested size to receive the image.
Get a Graphics2D for drawing on this image and let the JPanel paint on it.

    JPanel panel = ...
    BufferedImage image = new BufferedImage(200, 200, TYPE_INT_ARGB);
    Graphics2D gg = image.createGraphics();
    try {
        gg.translate(-100, -20);  // start point of region negated
        panel.paint(gg);
    } finally {
        gg.dispose();
    }