I was using OpenCV’s cv::minMaxLoc() funtion in my code. But due to some restrictions on the device, I can’t call it from OpenCV and have to implement it myself from scratch. But it doesn’t work as expected. What is the issue with the code?

The way I was calling through OpenCV:

double minScore, maxScore;
cv::Point minClassLoc, maxClassLoc;
cv::minMaxLoc(classes_scores, &minScore, &maxScore, &minClassLoc, &maxClassLoc);

And my manual implementation:

void minMaxLoc(cv::Mat& input, double* minVal, double* maxVal, cv::Point* minLoc, cv::Point* maxLoc) {

    int rows = input.rows;
    int cols = input.cols;

    int minRow = 0, minCol = 0, maxRow = 0, maxCol = 0;
    double minValue = input.at<double>(0, 0);
    double maxValue = input.at<double>(0, 0);

    for (int row = 0; row < rows; ++row) {
        const double* rowData = input.ptr<double>(row);
        for (int col = 0; col < cols; ++col) {
            double value = rowData[col];
            if (value < minValue) {
                minValue = value;
                minRow = row;
                minCol = col;
            }
            if (value > maxValue) {
                maxValue = value;
                maxRow = row;
                maxCol = col;
            }
        }
    }

    *minVal = minValue;
    *maxVal = maxValue;
    *minLoc = cv::Point(minCol, minRow);
    *maxLoc = cv::Point(maxCol, maxRow);
}