It was an odd way to demo the tech as it was really quick. But what happens in the video is that the user holds a picture up in front of his face and nothing happens. Then he removes the picture to show his face and is immediately logged in. It seemed to happen much quicker than the other examples of unlocking, in the same video, that I assumed it was a video example of how the tech would work and not necessarily a real life demo. Obviously I could be wrong though.