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The Nonphotorealistic Camera
An anonymous reader writes "This article on Photo.Net describes a new type of imaging technique that finds depth discontinuities in real-world scenes with multiple flashes added to ordinary digital cameras. As depth discontinuities correspond to real 3D object boundaries, the resulting images look like line drawings. The same technique was used at this year's SIGGRAPH to create a live A-ha 'Take On Me' demo."
How about having a camcorder with several differently coloured light sources? By analyzing the correspondingly differently coloured shadows one could create depth information in real time.
Add this to moving around a room while filming it. It should be possible to create an accurate 3D-representation even with today's technology.
If the colours of the light sources we're properly matched any discoloration could probably be eliminated as well.
Food for thought.
.: Max Romantschuk
See the laparoscope demo. The technique is being used in surgery, and it just requires two flashes and a camera.
But I don't think it will be useful for 3d reconstruction, since the algorithm doesn't have information about the depth of the shadows/borders.
Singularity: a belief in the "God" idea with the "demiurge" relation inverted.
I think this is a quantum level above the Photoshop filters on an ordinary photo.
In a standard photo, where is light and where is dark is only an approximation to 3D properties from a specific angle
The use of multiple flashes gives a much more complete picture of depth.
The real question is what is the cost of this process, and how does it compare with laser modeling techniques?
If the cost and ease of use is not very low, i would say most of the uses of this technology would be better served by the capability of laser scanners to produce a high resolution digital 3D model of an object, rather than a 2D representation of a 3D object.
I know which one i would rather my surgeon was using i know that much!
Could this tech be used to help robots, or any computer really better understand it's evironment visually? As I understand it one of the problems facing robot optics is the lack of depth perception and identifying object bounderies, if they used optics in the nonvisable spectrum and basically walked around with they're flashes strobing happily along would that help these problems? The only problem I see with that is multiple robots flashes interfering with each other, so maybe it's only be used sparingly when absolutely needed? Or is this technology completely inappropriate for this application?
This technology is a long way from 3-D. First, this camera can only estimate relative depth not absolute depth. Thus, it might determine that the foreground object is half the distance to the camera as the background object, but have no estimate of the numerical distance of either object - the foreground could be 3 feet from the camera and the background would be 6 feet or the foreground could be 5 feet from the camera and the background would be at 10 feet.
Furthermore, this technology only sees edge discontinuities where a foreground object sits in front of a background object. Thus it cannot tell the difference between a circular disk in the foreground or a sphere in the foreground. Actually it is worse than that because the rounded edge of the sphere will cause errors in the estimation of the relative depth of the sphere vs. the background.
Even with these limitations, the technology could be quite useful in robotics. Combining multiple edge images using optical flow and knowledge of the robot's motion would yield a more accurate 3-D depth map at least for the purposes of navigation.
As for extending the technology, a second camera would do wonders for pinning down the distances to each observed edge. The system would still need separate software magic for mapping the front surfaces of objects (e.g. discerning the difference between a 3-D sphere and a 2-D disk).
Two wrongs don't make a right, but three lefts do.
It bothers me a lot that stereo photography has been around so long yet isn't ubiquitous yet. Modern digi-cams don't do this. You said it's been around for ages, I hope most people know you mean more than decades. A quick google search tells me 1839 at the latest. What is stopping it?
Putting 2 sensors on a digi cam (photo or video) is not a difficult trick. You store the images in a format that supports 2 channels (left/right) and you can view them on any monitor with a simple pair of USB controlled glasses that flicks back and forth blacking out each eye. Also there are already 3d monitors out there that work without glasses.
Print out one channel for a 2d image or use photoshop filters to create red/blue 3d prints. Or even send images to a printer and get back those wheels used in those orange stereoscope toys.
If I had this ALL my pictures would be 3d. For that matter all movies should be 3D. IMAX has a workable solution but I think every movie should be shown this way. People would even buy their own personal polarized glasses that are more comfortable than the pairs handed out at the show.
I've been eyeing a digital-SLR for quite some time, for the cost of one of those I'd gladly turn my attention to a 3D capable camera with lower quality. And if the grandparent post is right something similar should be possible for SLR cameras without using 2 huge lenses. Although I'd submit that you can't always control the lighting.
Every now and then a red/blue 3D image comes up on APOD or elsewhere and I kick myself for not having a cheap pair red/blue glasses.