Reduce false detection of template matching in opencv

int MatchingMethod( int iMatchMethod, void* )
{
    cv::Mat ref = cv::imread("D:/Temp/InputImage.png");
    cv::Mat tpl = cv::imread("D:/Temp/TemplateImage.png");
    
    if(ref.empty() || tpl.empty())
        return -1;

    cv::Mat gref, gtpl;
    cv::cvtColor(ref, gref, CV_BGR2GRAY);
    cv::cvtColor(tpl, gtpl, CV_BGR2GRAY);

    cv::Mat res(ref.rows-tpl.rows+1, ref.cols-tpl.cols+1, CV_32FC1);
    cv::matchTemplate(gref, gtpl, res, CV_TM_CCOEFF_NORMED);
    cv::threshold(res, res, 0.1, 1., CV_THRESH_TOZERO);

    while(true) 
    {
        double minval, maxval, threshold = 0.6;
        cv::Point minloc, maxloc;
        cv::minMaxLoc(res, &minval, &maxval, &minloc, &maxloc);

        if(maxval >= threshold)
        {
	    cout <<"\n Template Matches with input image\n";

            cv::rectangle(
                           ref, 
                           maxloc, 
                           cv::Point(maxloc.x + tpl.cols, maxloc.y + tpl.rows), 
                           CV_RGB(0,255,0), 2
                         );
            cv::floodFill(res, maxloc, cv::Scalar(0), 0, cv::Scalar(.1), cv::Scalar(1.));
			break;
        }
        else
	{
	    cout << "\nTemplate does not match with input image\n";
            break;
	}
    }
	
    cv::imshow("reference", ref);
    cv::waitKey();
    ref.release();
    tpl.release();
    return 0;
}