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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."
It's interesting to see that people finally wanted to try to obtain from their hardware what they'd usually expect Photoshop filters to do.
I am for example very happy with my Motorola v550 cell phone camera which takes the trashiest but also most colorful nunrealistic photos.
Trolling using another account since 2005.
A live "Take On Me" video?
:P
People always ask how we'll know when technology will go too far, and I think we've just found out.
Is here
has slowed to a crawl, Here's the cache.
You are mistaken. The final image is the 'equivalent' photoshop filter, and it's showing what a poor job it does in contrast to the third image, a good image, from the multiflash.
Try reading the article, the last 3 images use different techniques and are for comparison. Jeez
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
This technique sounds like it could be useful for 3d reconstruction problems. The main issue in, for example shape from stereo algorithms is accurately finding depth discontinuities, and it can be nigh on impossible with a textureless, evenly lit surface.
Having said that, I'm not sure whether it would be better than existing solutions for that sort of thing, for example structured light.
Disclaimer: I am not a expert on graphics technology.
But look at the second image in the final set, it's clearly able to detect the edges of things. I'm not even sure what the filter in the last image is for.
And I'm not sure what you mean by "reproducing what can already bt produced". There are other multiple-image processing engines that can do line drawings and even 3d from multiple sources, but the thing is, they all require multiple cameras and calculating the slight offset in objects from different sources.
What's interesting about this new technique is that it uses the shadows from the flashes to determine edges and depth. Doing it entirely with lighting without multiple cameras is a really neat hack, imho.
3D cameras do exist ... though the one that I saw was a fairly substantial beast. About the size of a phone booth, you stand in the middle and well-calibrated cameras all around you take pictures, generating a 3D model of whatever's in there.
It was strange seeing a surprisingly high resolution 3D model of me on screen seconds after I'd stepped out of the thing.
The depth edge maps bear a superficial resemblance to phase congruency maps. It's the best edge detection method I've come across, and works on ordinary 2D images. Check out some examples on Peter Kovesi's pages, there's also some code for download.
Escher was the first MC and Giger invented the HR department.
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?
Don't encourage him, it's a bad habit.
Jolyon
Please read my Canon EOS tech blog at http://www.everyothershot.com
Pfft. Red eye? That's two flashes. With four flashes, you need to run the forked tail and horn remover, too.
A nonphotorealistic camera for Lexmark's entire line of nonphotorealistic printers!!
"Capital punishment makes the state into a murderer. Imprisonment makes the state into a gay dungeon-master"
I think this is a quantum level above the Photoshop filters
So, you mean, this is the tiniest possible improvement over Photoshop filters?
For those that are uneducated in graphics, the engine photos show two comparative methods:
The TOP row shows how the camera output is good enough to be used as a technical drawing- it requires very little modification or touch-up.
The BOTTOM row shows how a Photoshop filters butcher the image and the result is completely useless. No amount of touch up could help that image.
Furthermore... NO THIS CAMERA CANNOT BE USED ON MONOCHROME IMAGES. It can't be used on any kind of images, and it isn't a post-filter. There isn't any edge detection involved.
The 4 flashes cause shadows to be cast in 4 different directions and creates a composite from the difference. If the subject DOESN'T cast a shadow, then the camera won't work.
I assume this camera cannot be used to photograph the outdoor scenes, simply because the flashes will not render shadows at that great distance.
This is an brilliant method though, and the results are excellent (look at how the details in the spine pop out).
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.
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.