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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."
I wonder if this technology could be extended to allow one to quickly take a picture of a real world object and turn it into 3D models (for use in 3D Studio etc.). Obviously one would have to take multiple pictures (six?) to get a proper all round representation of the object.
Just a thought.
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!
from a specific angle
Reminds me of a Calvin&Hobbes strip where Clavin is in a perspectiveless world.
BTW, you can also play on the camera's limitations and move it while it's still busy catching the pic... some kind of artistical fuzz... When you take some colorful lights, you always get funny results after equalizing the whole pic with your favourite pic processing soft.
Trolling using another account since 2005.
First off, as the 2 posts above pointed out, the composite image is one in the top right,not bottom right. I would say the top one is useful but your free to feel however you want.
However,if you read carefully you see that the nifty aspect is that it gives depth information to images, even monochrome images. Just to start with this has applications for internal medicine (i.e. laparoscopy). This is cool.
What do you say to the man that has nothing? Cast it away!!
Oh, no. Will traced overlay pictures return for manuals if this is faster then optimizing the original CAD design for a consumer? I hope not, manuals can be pretty clear these days, I have no desire to return to those traced illustrations of the past even if it can be done automatically instead of by hand. Taking the time to optimize the original CAD technical drawings of a product in Freehand gives much better results.
The technique can be great, reading stone tablets with a flash dome is so much easier then trying to look at the real surface, but for most (consumer) uses two lenses will give more opportunities (to remove the background, to see "3D".
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?
I wonder if such a technogology could be used for biometric facial recognition. Since the lightsources are internal, it would be relatively simple get consistent refrence points from it.
Also, it would not be *AS* processor intensive, so you could take more photos from more angles.
Using autofocus, and a short depth of focus, you isolate figures even in crouds. Isolate the target from multiple photos, so you have more than one agle for a biometric.
If we can track the target in motion, we can assume that FRONT is aproxomately the direction they are traveling. Use and IR flash so that people don't get all paranoid (not saying they don't have a reason).
Even with glasses and a beard change it would be tough to fool the system.
I would rather be ashes than dust!
Speaking of non-photorealistic and real-time, this reminds of me NPR Quake.
Dan East
Better known as 318230.
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.
Had to mention this for those who didn't catch it in 2001. Some students in Wisconsin created a Quake II mod that converts the Open GL rendering engine output to non-photorealistic sketches. Looks like the A-ha video in realtime. I'd really like to see someone bring this to more modern 1st-person-shooters like Doom 3 or Quake 3.
NPR Quake.
$5 / month hosted VPS on linux = awesome!
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.
One of them is Canesta that makes a photo sensors that can make pictures that include deep maps.
To my surprise I see that they are running a contest were your can win 10000 $.
But I don't have time to participate myself, because I am writing on my masters. So enjoy the contest.
It seems like this could lend itself to some image compression techniques. Especially for web
image downloads, you could send the line drawing first and then fill in the interiors more quickly
because the colors of the interiors are likely to be homogenous. This would be a good alternative to the current technique of sending a low-res image first and then overwriting it.