How to create an array of pixel values?

Question

I am trying to create a double-scripted array that has all the RGB values of an image in java. Afterwards, I want to see whether the pixel is black or white. However, the following code gives me an ArrayIndexOutofBounds Error and I'm not sure why. Any help would be greatly appreciated!

int[][] imageArr = new int[image.getTileHeight()+1][image.getTileWidth()+1];
    for (int a=0; a<image.getTileHeight(); a++)
    {
        for (int b=0; b<image.getTileWidth(); b++)
        {
            imageArr[a][b] = image.getRGB(a,b);               
        }
    }

Stack Trace of error:

java.lang.ArrayIndexOutOfBoundsException: Coordinate out of bounds!
    at sun.awt.image.ByteInterleavedRaster.getDataElements(ByteInterleavedRaster.java:318)
    at java.awt.image.BufferedImage.getRGB(BufferedImage.java:888)
    at image2.main(image2.java:34)

The code looks ok to me. Is it possible that the `ArrayIndexOutofBoundsError` came from `image.getRGB()`? — pburka, Oct 20 '13 at 22:14
I'm not sure...the error states: "java.lang.ArrayIndexOutOfBoundsException: Coordinate out of bounds! (in sun.awt.image.ByteInterleavedRaster) — user1755178, Oct 20 '13 at 22:19
Do you have the full stack trace? Does it include `getRGB()`? Learning to read a stack trace is an essential Java skill. — pburka, Oct 20 '13 at 22:26
After the `ArrayIndexOutOfBoundsException` there should be a list of method names, file names and line numbers. Each line should start with the word "at". Copy and paste that into your question. — pburka, Oct 20 '13 at 22:32
Yes. The stack trace shows that the `ArrayIndexOutOfBoundsException` came from `java.awt.image.BufferedImage.getRGB()`. — pburka, Oct 20 '13 at 22:43
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/39605/discussion-between-user1755178-and-pburka) — user1755178, Oct 20 '13 at 22:46
This [question](http://stackoverflow.com/questions/10880083/get-rgb-of-a-bufferedimage) may be of help to you — Java Devil, Oct 20 '13 at 22:50

score 0 · Answer 1 · answered Oct 20 '13 at 22:38

If you are wanting to get it for the complete image then you need to use getHeight and getWidth not getTileHeight and getTileWidth in your loops and array initialisation.

These are causing the getRBG to throw the ArrayIndexOutOfBounds as it trying to get the image of the Raster data embedding within your BufferedImage

How to create an array of pixel values?

1 Answers1