Posted on 08/31/2008 12:38:12 PM PDT by neverdem
The virtual worlds in computer games provide a realistic backdrop to the action. But step too close and the effect is lost – you'll see that textures and patterns are usually displayed on flat surfaces that look dull and artificial.
A simpler way to add depth to textured surfaces could change that.
The new technique can reconstruct the depth of a surface simply by taking two photos of it – one with a flash and one without (see video, right). Merely analysing the resulting shading patterns can capture the surface's 3D texture.
Until now making realistic textures required the use of bulky and expensive laser scanners, says Mashhuda Glencross at the University of Manchester, UK. And the process is really time-consuming, she adds.
3D in a flash Glencross and the Manchester team worked with Gregory Ward at Dolby Canada in Vancouver to develop their quick and cheap alternative.
At the heart of the technique is the assumption that the brightness of a pixel in the image is related to its depth in the real scene. Parts of the surface deep in a crack or pit receive light from a restricted area of the sky, and appear relatively dark.
By contrast, protruding parts of the surface receive more light and appear brighter in a photo.
Correct colours But the colour of the surface also affects its brightness in a photo. With the same illumination, light-coloured spots appear brighter than dark ones.
Taking a photo using the flash removes that effect. The surface is flooded with light and the camera can record the true colour of every part it can see, even those in cracks and pits.
The flashlight image is paired up with a photo taken without extra lighting. Software then compares the brightness of every matching pair of pixels in...
(Excerpt) Read more at technology.newscientist.com ...
What the hell has this got to do with the price of eggs?
Fascinating stuff.
Don’t need a flash to accomplish this, just two photo’s with the light source of one at a lower angle. There’s nothing really new and exciting about this.
Then why did they write the fourth paragraph?
"Until now making realistic textures required the use of bulky and expensive laser scanners, says Mashhuda Glencross at the University of Manchester, UK. And the process is really time-consuming, she adds."
Great post!
Thanks neverdem.
A group of students in the US have applied this technique to video, which is even crazier. Tens of thousands of still frames from the video are combined to create 3D visuals.
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