Take a look at what they've done. The basic idea is that the video is "on rails", moving forward on its own, but at any point you can pause and move around the

Take a look at what they've done. The basic idea is that the video is "on rails", moving forward on its own, but at any point you can pause and move around the objects from the video. Then you can go back to the video and it interpolates back to the recorded track. I loved what they did, but it didn't help me understand quaternions ;(