Creating 3D Computer Graphics From 2D HDTV Camera

photon jockey writes: "Everyone knows that holograms are cool! But these three dimensional images are hard to make and need special conditions to view. A group from The University of Tokyo have taken a step toward 3D displays with this paper in Optics Express. Using a HDTV camera they effectively capture the light rays passing through a plane from a lit scene and then reconstruct the three dimensional geometry of the scene. Some pretty movies are available from the same page to show this. The paralax is limited by the size of the CCD and the distance to the object. From the paper: In the field of computer graphics (CG),the use of real images has been attracting attention as a method of attaining image synthesis that results in a more photo-realistic quality. This field of technology is called image-based rendering. The authors have attempted to solve this problem, by applying the approach of 3-D display technology, in which light rays are the most primitive elements of visual cues. "

Comments

Re:Could Someone explain this to me

[merlin_jim]

I have the same problem with the PDF viewer, but I can explain the concepts behind any sort of light-based 3D capture.

It basically depends on polarization. All light is polarized, meaning that the electric wave and the magnetic wave that make up a photon are orthogonal (at right-angles within a plane) to each other. Most light is randomly polarized... that is, it bounces around at random with no structure to it. That's why lasers are commonly used in holography; it provides a polarized constant.

A traditional hologram is made by bouncing polarized light off an object (possibly from several different angles) and then exposing a piece of film to both the original, highly polarized light, and the light that is reflected off the object. When light is reflected, you change it's polarization to be (typically) parallel to the incident of reflection.

This makes miniature "grooves" in the image... they're virtual grooves, meaning they have no height, but all the same they selectively reflect only light of certain polarizations. Then, by shining the same type of polarized light on the exposed image, different angles of viewing select different polarizations, meaning different angles of viewing on the target object.

As for how this technology works, from what I can tell they're capturing the color and polarization of all the photons. This, combined with the width of the CCD, allows you to capture 3D information about the subject matter. If you were to add a source of polarized light to this thing, you could probably through the use of mirrors capture EVERY angle, just like a traditional hologram.

As a matter of fact, it doesn't even have to be visible light. Infrared will work fine, though you'll only get a rough gray-scale. But then, you don't need to be shining red/green/blue laser light around everywhere...

Won't the matrix people be mad at this! They spent Some Great Value Of Hard Earned Cash (SGVOHEC) to develop bullet-time, and now they can just use what turns out to be existing technology, making that expenditure of SGVOHEC a moot point.

Oh well, maybe the superbowl people will get with it next time so that my super-zooming rotating image of the QB won't jerk around like a 10-year-old computer trying to run quake...

Porn!

[OlympicSponsor]

www.opticsexpress.com, huh? Sure, maybe you can tell the boss they are "Optics Express" but we all know it's reall "Optic Sex Press". Motto: "Where girls push themselves against your eyeballs"
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