title: How to subtract two images using python opencv2 to get the foreground object
body: <p>Is there any way to subtract two images in python opencv2 ? </p>
  
  <ul>
  <li>Image 1 : Any image (eg. a house Image) (static image)</li>
  <li>Image 2 : The same Image with an Object (In house, a person is standing...) 
  (static image + dynamic objects) </li>
  <li>Image 3 = Image 2 - Image 1</li>
  </ul>
  
  <p>If we subtract <code>Image2</code> from <code>Image1</code> means <code>Image3</code> should give <code>Object(person)</code> only. </p>