Question

I have two grayscale Png files( https://i.stack.imgur.com/8RGh4.jpg ) that I want consider as a 2d array, so that I can apply masks to them.

What is the best way of doing this?

and if possible converting back, so I can show the masked images as my program works.

This is an assignment for university, just need to know how to get the data in, then I will do the rest.

Many thanks

Answer 1

try {
    URL url = new URL("http://i.imgur.com/Ad0AP.png");
    Image image = Toolkit.getDefaultToolkit().createImage(url);
} catch (MalformedURLException e) {
} catch (IOException e) {}

You can then convert the Image instance to a BufferedImage using this:

public static BufferedImage toBufferedImage(Image image) {
    if (image instanceof BufferedImage) {
        // Return image unchanged if it is already a BufferedImage.
        return (BufferedImage) image;
    }

    // Ensure image is loaded.
    image = new ImageIcon(image).getImage();

    BufferedImage bufferedImage = new BufferedImage(image.getWidth(null), image.getHeight(null),  BufferedImage.TYPE_INT_ARGB);
    Graphics g = bufferedImage.createGraphics();
    g.drawImage(image, 0, 0, null);
    g.dispose();

    return bufferedImage;
}

and then get the width and height of the image to loop through it, after you have that you can pretty much put it in any data structure you like. i.e:

int w = i.getWidth();
int h = i.getHeight();

int[][] array = new int[w][h];
for (int j = 0; j < w; j++) {
    for (int k = 0; k < h; k++) {
        array[j][k] = i.getRGB(j, k); // or whatever
        System.out.println("jk=" + array[j][k]);
    }
}

now.. do the rest 🙂