title: OpenCV - remap() - getting black pixels
body: <p>I'm using an STMap to map a .jpg image using <code>remap()</code>. </p>
  
  <p>I loaded my STMap, split the channels and converted each channel matrix to <code>CV_32FC1</code>. 
  I checked them and it worked - each matrix displays correctly and all of its values are between 0.0 and 1.0. </p>
  
  <p>However, when i try to use the <code>remap()</code> function:</p>
  
  <pre><code>Mat dst;
  remap(image4, dst,map_x,map_y,INTER_LINEAR,BORDER_CONSTANT,Scalar(0,0,0));
  imshow( "Result", dst );
  </code></pre>
  
  <p>It just displays a black image.</p>
  
  <ol>
  <li><code>image4</code> = my .jpg image </li>
  <li><code>map_x</code> = grayscale CV_32FC1 (red channel
  of the original STMap) </li>
  <li><code>map_y</code> = grayscale CV_32FC1 (green channel
  of the original STMap)</li>
  </ol>
  
  <p>What could be the problem?</p>
  
  <p>Thanks!</p>