title: OpenCV rgb value for cv::Point in cv::Mat
body: <p>I've looked at different questions already here on StackOverflow, but none seems to helps.
  What I want to do is quite simple: I have a <code>cv::Point</code> and I need to get the RGB value for the pixel at that point in a <code>cv::Mat</code> so that I can compare it with a stored RGB value.</p>
  
  <p>Now this should be very easy but I've tried 1001 different ways and it just doesnt work for me.</p>
  
  <p>Someone please help me out of my misery!!</p>
  
  <p>edit:
  both answers below work!
  I'm kinda new with C++ and didn't know that outputting a <code>unsigned char</code> through <code>cout</code> gives a questionmark!
  <code>printf</code> offcourse gives the right value!!</p>