From the beginning of this chapter until now, we have focused on the background subtraction approaches that try to model the background of the scene using ordinary cameras and then on applying frame differencing.

In this section, we will take a different approach. We will set how far we want our objects to be considered foreground and background, which means removing the background by selecting a depth parameter. Unfortunately, this can not be done using a single ordinary camera in a single shot, so we will need a sensor that tells us the depth of objects or try to determine depth from stereo, which is not in the scope of this chapter. Thanks to both gamers and several efforts from all around the world, this device has become a commodity and it is called a Kinect. Some attempts can be made to use two cameras and try to get depth from stereo,...