calculating the distance between 2 points openCV c++

Question

Basically i have to figure out whether the label on on object is straight. I have an edge image of the object. I would like to calculate the distance between the 2 edges on either side in a single row. My algorithm involves iterating through a row until a white pixel is found. Then calculating the number of black pixels until the next white is found. However when i run the code the answer is always zero.

Code:

for(int i = 0; i < img.cols; i++)
{

    int num = nms_result.at<int>(i,100);
    //cout <<num<<endl;
    if(num > 0) { 
               stage2 = true;
    }

    if (stage2 ==true)
        counter4++;
    { 

        int num2 = nms_result.at<int>(i,100);
        ;

        if ((num2 < 1) && (counter4 >=1 )) {
                counter2++;
        }       

                else counter4 = 0;

    }


    }

I have tried a lot of things but none seem to work.

Answer 1

Problem number 1: If I'm reading your code right, 'num' and 'num2' are always the same, since they're in the same loop.

Problem number 2: What's the output here? a little hard to tell with your formatting. Consider using some indentations with your nested ifs.