How to blend two image

Question

I want to blend two images together with a ratio of 4:1

the result should be something like this

Answer 1

The question is vague, but you could use the 2D Graphics API

Take a look at 2D Graphics and Compositing Graphics in particular...

So using the following images (base on left, overlay on right)

try {
    BufferedImage base = ImageIO.read(new File("base.jpg"));
    BufferedImage overlay = ImageIO.read(new File("overlay.jpg"));

    Graphics2D g2d = base.createGraphics();
    g2d.setComposite(AlphaComposite.SrcOver.derive(0.5f));
    int x = (base.getWidth() - overlay.getWidth()) / 2;
    int y = (base.getHeight() - overlay.getHeight()) / 2;
    g2d.drawImage(overlay, x, y, null);
    g2d.dispose();

    ImageIO.write(base, "jpg", new File("Blended.jpg"));
} catch (IOException e) {
    e.printStackTrace();
}

Resulting in...

Take a look at...

• Reading/Loading an Image
• Writing/Saving an Image

for more details...