title: OpenCV: output image is blue
body: <p>so i'm making this project where i'm making the reflection of an image on OpenCV (without using the flip function), and the only problem (i think) to finish it, is that the image that is suppose to come out reflected, is coming out as all blue.</p>
  
  <p>The code i have (i took out the usual part, the problem should be around here):</p>
  
  <pre><code>Mat imageReflectionFinal = Mat::zeros(Size(220,220),CV_8UC3);
  
  for(unsigned int r=0; r&lt;221; r++)
      for(unsigned int c=0; c&lt;221; c++) {
         Vec3b intensity = image.at&lt;Vec3b&gt;(r,c);
         imageReflectionFinal.at&lt;Vec3b&gt;(r,c) = (uchar)(c, -r + (220)/2);
      }
  
      ///displays images
      imshow( "Original Image", image );
      imshow("Reflected Image", imageReflectionFinal);
      waitKey(0);
      return 0;
  }
  </code></pre>