title: Background Subtraction for Road Traffic Monitoring
body: <p>I have to detect cars on a video stream (recorded) and provide some traffic data.  I have read that background subtraction is the most important step so that we can be able to extract foreground objects.</p>
  
  <p>The question is, how do we do this for colour frames? Articles I have read talk more of black and white images. </p>
  
  <p>I would like to use automatic background removal, which uses frame differencing (in my understanding). </p>
  
  <p>If I did the removal in gray scale, would I still be able to replay the video with the tracked object in colour? Because the point is being able to show the tracked car on the original video.</p>