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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
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
I know it ain't really a 3d mapper but is it a quick way to grab info that could be later given a more in-depth scan?
Could this technology be modified to produce a good 3d mapper?
What's it's claim 2 fame? Shadow-comparison , right? Length-of-shadow=height-of-object, yes?
You see, edge detection is funny.
Real world discontinuities, what they mean is, you run an edge detection algorithm on the distance signal.
This will not find edges in newspaper print.
No edge detection system is perfect - even this which uses spatial edges.
There is no real new technology, the multiple flash cameras are amazing and beat any faked edge detection hands down.
I do think they have awesome capabilities to allow computers to do what our eyes do, which is segment and label areas of our vision, and may make the blighters useful!
Computer aided sensory vision [audio descriptive alerts] could do amazing things for blind people, if we get there before they make artificial eyes better than 16x16 resolution.
#hostfile 0.0.0.0 primidi.com 0.0.0.0 www.primidi.com 0.0.0.0 radio.weblogs.com
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.
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!!
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?
With four flashes, the first thing you better do before any fancy schmancy edge detection algorithm is run the red-eye removal filter!
Don't encourage him, it's a bad habit.
Jolyon
Please read my Canon EOS tech blog at http://www.everyothershot.com
This would be great for technical manual writing. Help you take pictures of the mechanicla interfaces.
Evolution or ID?
3D analysis requires stereo-pair of images, like this. Alternative would be to use some kind of radar or sonar, measuring time-differences of bounced signals, etc. Those and other methods for 3d digitizing.
Preserve old classics: copy your collection onto all hard drives.
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!
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).
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.
FYI, they're called "View-Master," and apparently they're no longer available in the vertical-wheel red/orange style I had as a kid.
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.
If autofocus (or any other method) from differnet angles allows for this enhancement, this technique can be used to 'cut' the image into different focus layers.
Piece the layers together, and you get a photo that has depth of field and is much sharper at each level.
The layer information could be stored seperately for later processing or combined with only a little fudging to give a weighted blur to the non-primary layer(s). Keeping the layers seperate and doing a comparison would also allow editing tricks such as cutting out objects at a specific depth or performing color enhancements on each level.
A firewall can not protect you from yourself. Turn off what you do not need. Do not use the firewall to do your work.
You'll notice a lot of pro photographers have devices to move the flash further from the lens: either tall stalks with the flash at the end, handheld flash units on wires (to be held arm-outstretched in the non-camera hand), or even RC flash units on tripods several metres from the camera.
Sure, and they usually also have some sort of diffuser or umbrella with their flash. Or they'll bounce their flash off the ceiling for the same effect. Or multiple flashes are set up so that each one fills in the shadows from the other units. At the macrophotography extreme, you use a ring flash that surrounds the lens to provide flash from every direction and eliminate shadows (that the camera can see) altogether. These are all just ways to reduce the harsh, distracting shadow that comes from a single, direct flash in a low light situation.
But with a little consumer point-and-shoot, where you've got a tiny flash offset just a bit from the lens, you tend to get a dark shadow line around the edge of your subject that's pretty unattractive. The brilliant thing here is that these guys realized that the same effect can be put to use in a really simple and interesting way. They turned something most people see as a problem into a great solution for a different problem.
That's some pretty impressive edge detection, thanks for pointing it out. A related problem is to identify areas in an image that are the same thing. The best algorithm I know of for segmenting images is Leo Grady's brand new iso parametric graph partitioning method. His work is at http://cns.bu.edu/~lgrady/. His PhD thesis is probably the best place to start.