One Step toward Star Trek viewers?


Okay, I suppose given a little thought it's not that close yet but check it out.  Yesteday Slashdot linked to an article about a way to see things it seems like you should not be able to see.

Basically there is some method which says that if you have a light coming from a projector and you take a picture of something that light is lighting up from digital camera you can compute what the object looks like FROM THE PROJECTOR's point of view.

Here's an example.  They setup a camera, a card, a book and a projector like this


Given a scene like above the light normally goes from the projector bounces off the face of the card, off the book and into the camera.  Using the method mentioned using only the knowledge of the position of the camera, projector and the images from the camera they can compute the light going the other way as though the camera and projector were swapped.

Here's what the camera sees.

As you can see the camera can only see the back of the card.  But, using the method mentioned here is part of the card

That picture of the card was never "taken".  It is computed by turning pixels on and off on the projector and computing all the reflection data from off the book as seen from the camera!  Amazing!  Follow the link above for a more detailed explaination and a video example.