title: Detecting Red Green and Blue by cancelling background
body: <p>I have continuous image acquisition and have a white paper at the background of the camera (facing the camera)</p>
  
  <p>The image with just the white background is producing a greenish blue tinge due to light bulbs used in the room which is resulting in output as <code>GREEN</code> for the following code</p>
  
  <pre><code> green = im(:,:,2);
     red = im(:,:,1);
     if sum( green(:)) &gt; sum(red(:))
         disp('green');
     else
         disp('red');
     end
  </code></pre>
  
  <p>Is there any way to <code>CANCEL</code> the white paper background for processing only the color objects that will be placed in front of the camera ??</p>
  
  <p>The Color objects will be RED, GREEN and BLUE squares</p>