Using IR camera + IR light?

The main problem in the tracking the people on the street is the changing lighting conditions as the exhibition will be open from morning to the evening. We were doing some research about it and found this example of the usage of IR camera + IR light to create higher contrast:


Same space in IR:


Pictures are from: http://vvvv.org/tiki-view_forum_thread.php?forumId=7&comments_parentId=11180