title: C++ OpenCV not drawing circles on mat image
body: <p>I've got images that are displayed using cv::Mat and I'm trying to highlight certain points with circles as so</p>
  
  <pre><code>cv::namedWindow("image_window");
  cv::Mat image = cv::imread(fileLoc);
  
  cv::imshow("image_window", image);
  
  /*for (unsigned int b = 0; b &lt; points.size(); b++)*/
  if (points[0].num_parts() != 0)
  {
      for (unsigned int c = 0; c &lt; points[0].num_parts(); c++)
      {
          dlib::point pp = points[0].part(c);
          cv::circle(image, cv::Point(pp.x()/2 , pp.y()/2 ), 3, cv::Scalar(0, 0, 0));
          std::stringstream ss;
          ss &lt;&lt; (c);
          /*cout &lt;&lt; c &lt;&lt; endl;
          cout &lt;&lt; pp &lt;&lt; endl;*/
          cv::putText(image, ss.str(), cv::Point(pp.x() , pp.y() ), cv::FONT_HERSHEY_PLAIN, 0.8f, cv::Scalar(0x99, 0xFF, 0xFF));
  
      }
  }/**/
  </code></pre>
  
  <p>However, nothing is displayed on image other than the image in question. Where am I going wrong and how can it be fixed?</p>