coordinates out of bound

Question

I made a program to mirroring of an image but the code below gives an error:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 
Coordinate out of bounds!
at sun.awt.image.ByteInterleavedRaster.setDataElements(Unknown Source)
at java.awt.image.BufferedImage.setRGB(Unknown Source)
at algoritm.MirrorImage.applyAlgoritm(MirrorImage.java:43)
at ImageProcess.main(ImageProcess.java:36)

Here is the source code:

package algoritm;   
import java.awt.image.BufferedImage;   
public class MirrorImage implements Algoritm{   
private BufferedImage bufferedImage;
private int width;
private int height;
//getter si setter
    public MirrorImage(BufferedImage bufferedImage) {
        this.bufferedImage = bufferedImage;

    }

    public BufferedImage getBufferedImage() {
        return bufferedImage;
    }

    public void setBufferedImage(BufferedImage bufferedImage) {
        this.bufferedImage = bufferedImage;
    }

    public void applyAlgoritm() {
        width = bufferedImage.getWidth();
        height = bufferedImage.getHeight();
        for(int y = 0; y < height; y++){
            for(int lx = 0, rx = width*2 - 1; lx < width; lx++, rx--){
                int p = bufferedImage.getRGB(lx,y);
                bufferedImage.setRGB(lx, y, p);
                bufferedImage.setRGB(rx, y, p);
              }
        }
    }
}

I think is something wrong with the second setRGB. If I comment on it, my error disappears, but the program does not do the right thing.

Did you try debugging your Programm? If not you can checkout this link on how it can help you: https://stackoverflow.com/questions/25385173/what-is-a-debugger-and-how-can-it-help-me-diagnose-problems — M.Dan, Dec 28 '18 at 15:49

score 0 · Accepted Answer · answered Dec 28 '18 at 15:59

0

It seems image you are trying to modify is not resized. Try to instantiate a new clean buffered image with double width

At the first iteration here:

width = bufferedImage.getWidth();
rx = width*2 - 1;
  ...
  bufferedImage.setRGB(rx, y, p);

rx is out of bounds, try, in your constructor, to create a new clean image

BufferedImage newImage = new BufferedImage(2 * bufferedImage.getWidth(),  bufferedImage.getHieght(), BufferedImage.TYPE_INT_ARGB);

and mirror on top of this one, so in your loop

//read from the old one 
int p = bufferedImage.getRGB(lx,y);

// and write in the new one
newImage.setRGB(lx, y, p);
newImage.setRGB(rx, y, p);

answered Dec 28 '18 at 15:59

sabau

166
1
11

But BufferedImage It is not a predefined class? I did not make any constructor for it. – Vasilica Bogdan Dec 28 '18 at 16:50
I don't understand where i need to put the new image constructor. – Vasilica Bogdan Dec 28 '18 at 18:15
The third line of your code define a class `BufferedImage` and few lines underneath you've created a setter (sorry I wrote constructor because it could have been his constructor in my mind, but probably a static class/method will work even better here). public void setBufferedImage(BufferedImage bufferedImage) { this.bufferedImage = bufferedImage; this.mirroredImage = new BufferedImage(2* ...) } – sabau Jan 02 '19 at 09:20

score 0 · Answer 2 · answered Dec 30 '18 at 19:53

setRGB(int x, int y, int rgb)
Sets a pixel in this BufferedImage to the specified RGB value.

I am not a regular java programmer but when I read the docs for setRgb() function as you can see above x and y holds the coordinates of the pixel where the rgb is the new pixel value. When I look at your for loops, in the second loop you have bufferedImage.setRGB(rx, y, p); in which you are trying to set rx as x value which is at the beginning is rx = width*2 - 1; and no doubts this exceeds the image width. So, I suppose you need to reconsider your algorithm to solve your problem.

coordinates out of bound

2 Answers2