How to convert a 2d array of integers to an image in java?

Question

I have an array of positive integers. How would I display this as an image? I do not already the range of values that the array contains or the size of the array. A similar question was asked here. But I do not know the possible values without searching a possibly very large array. What is the best way of doing this with regards to efficiency and length of code?

Here is a small example of what the data could be

    0   2   4   6   8   10  12  14  16
    2   2   6   6   10  10  14  14  18
    4   6   4   6   12  14  12  14  20
    6   6   6   6   14  14  14  14  22
    8   10  12  14  8   10  12  14  24
   10   10  14  14  10  10  14  14  26
   12   14  12  14  12  14  12  14  28
   14   14  14  14  14  14  14  14  30
   16   18  20  22  24  26  28  30  16
   18   18  22  22  26  26  30  30  18

What file format are you shooting for? A BMP image header would be the first 14 bytes of your array I think. — andrewdleach, Jul 01 '15 at 19:24
I do not care that much about the file format unless it decreases the efficiency considerably. — Halbort, Jul 01 '15 at 19:37

score 3 · Accepted Answer · edited May 23 '17 at 11:58

3

Take a look here.

int xLenght = arr.length;
int yLength = arr[0].length;
BufferedImage b = new BufferedImage(xLenght, yLength, 3);

for(int x = 0; x < xLenght; x++) {
    for(int y = 0; y < yLength; y++) {
        int rgb = (int)arr[x][y]<<16 | (int)arr[x][y] << 8 | (int)arr[x][y]
        b.setRGB(x, y, rgb);
    }
}
ImageIO.write(b, "Doublearray", new File("Doublearray.jpg"));
System.out.println("end");

Now, refactor this code to read a proper input.

edited May 23 '17 at 11:58

Community

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answered Jul 01 '15 at 19:31

Aleksandar

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Can you vote up for the answer when it was useful to you? :) – Aleksandar Jul 01 '15 at 19:42
1

I tried that but I just joined today so my reputation is less than 15. :-( – Halbort Jul 01 '15 at 19:45

How to convert a 2d array of integers to an image in java?

1 Answers1