Heuristics to know correct order

Question

Well , I have a image in grey scale with his rows in a different order , so i thought in order the rows with a fitness function to know which order is the best i did the following heuristics:

for(int i=0;i<or.size()-1;i++) {
        for(int j=0;j<imagen[0].length;j++) {
            aux+=imagen[or.get(i)][j];
            aux2+=imagen[or.get(i+1)][j];

        }
        fitness+=Math.abs(aux-aux2);

    }


    return fitness;

what i am doing is to sum the grey of each row and see the different with the next row. I think that the correct order is the rows with less variation , so the correct order should be the order with the smallest fitness. But it doesn't work , any idea about how to change the heuristics to know the best order?

Adding some information to the problem : The image is given as a matrix with the pixel information , but the rows are in an incorrect order , the columns are fine.

Answer 1

I resolved with calculating the distance between each pixel and his neighbors , that means : distance = sum ( abs(current-corner1)+abs(current-corner2)+abs(current-top)... etc...