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Math to Crack Deep Impact Blurry Vision Problem
starexplorer writes "NASA announced that they believe they have a solution for the Deep Impact mission's blurry vision problem: math. Although the craft will still snap blurry pictures of the Tempel-1 comet, mathmetical manipulation will help scientists clear up the images once they make their way back to Earth. A special report and viewing guide are also available at SPACE.com."
using the same words, i made a much better headline.
"blurry vision math to impact deep crack problem"
it's a process called deconvolution, right? I did this as a project for sophomore year astronomy... which i believe involved asking on slashdot about it.
I'm not sure if it was a photoshop plugin or a standalone filter, but the filter was able to derive sharp pictures from the bokeh of photographs.
Essentially, it calculated the ring of blur and interpolated the data and was able to resolve out-of-focus areas. The sample photos were either of gorillas or pandas. I'm sure someone will have a link.
Very space opera.
How did this get a -1 rating? It should be modded informative or at least funny.
The early Hubble pictures suffered from optical distortion due to a miscalculation on what the shape of the mirror would be in obit, and NASA also fixed that problem using digital image filtering techniques to reconstruct a clear image. The key was that they had a precise model of the distortion and that it was invertible.
Although the craft will still snap blurry pictures of the Tempel-1 comet, mathmetical manipulation will help scientists clear up the images once they make their way back to Earth.
Scientists will also use Photoshop to remove any zits, butt dimples, and eyebags the comet may be suffering from.
Math in space you say? What will they think of next?!
Deconvolution has been around for many decades.
Whiskey. Tango. Foxtrot. Dude.
Beware of he who would deny you access to information, for in his heart he dreams himself your master.
Tilt your head to the side and Squint a bit!
liqbase
No, the parent is correct. Before the COSTAR correctional optics package was launched to fix Hubble's spherical aberation problem, NASA engineers were able to digitally de-convolve the aberations out of the image. The digitally-manipulated results weren't as good as the ones COSTAR optics eventually offered, but they did help some initial observing runs.
make world, not war
The Solar Maximum Mission satellite was repaired in 1984, long before Hubble was even launched. The repair mission was STS 41C.
Toronto-area transit rider? Rate your ride.
The solution to my blurry vision problem is to keep the number of vodka-sodas in the single digits.
Damn I love coding loaded: Best. Comments. Ever.
The only thing that made that horrible movie watchable was the vision blur inducing alcohol. Math fixes alcohol blur? Right...
How about "Math fixes hangover" instead?
Why don't we have adaptive image processing "glasses"? Can't some human vision problems be corrected by preprocessing an image, to "antidistort" it? The inverse distortion from the vision defect would return the image to "normal". Such a device could be recalibrated with test targets, so a wearer wouldn't need to consume valuable optometrist time for revised prescriptions. With some work, they could become light enough that they'd rival lenses, or even surpass them in some real coke-bottle cases. And we'd have a huger market for info display goggles.
--
make install -not war
Hubble was launched in 1990. The servicing mission wasn't until 1993. In between, they did indeed rely on math to get useable images out of hubble.
You know, the physicist who as a kid in the neighborhood could "fix radios by thinking."
Don't disappoint your bird dog. Go to the range.
http://www.cs.brown.edu/exploratories/freeSoftware /repository/edu/brown/cs/exploratories/applets/con volution/convolution_guide.html
"The key operation we perform, both in the theoretical development and in the implementation of filtering, is convolution. This applet allows students to understand the process of convolution. First they create a signal and a filter function to convolve. Then, they place the filter function when they see the product function of the two original signals. In a final graph below, they build up the convolution, seeing the area under the product curve correspond to the value of the convolution at that point.
This applet is useful in understanding both how convolution works and what the effects are of specific signals being convolved together."
Deconvolution.
FTFA: The team will use a process, called deconvolution, to remedy the situation. Deconvolution is widely used in image processing and involves the reversal of the distortion created by the faulty lens of a camera or other optical devices, like a telescope or microscope.
If NASA were smart and hired poets, they would just look at the blurry images and say, "Interesting".
Raise your children as if you were teaching them to raise your grandchildren, because you are.
yeah. but they never got a very good set of kernels. because of the nature of the flaw(s), the psfs varied across the image and didn't do so continuously. they got part of the way there, but it was never even close. if only there had been a decent test pattern set lying around in space.
actually it wasn't just NASA engineers. they had an open call for help, and alot of people worked on the problem. which was very cool.
All right, I know I shouldn't be replying to flamebait but here goes.
e w/motiondeblur.html/
It is in fact possible to at least partially reconstruct blurry images as long as you have some idea about what kind of distortion or motion is causing your problems. In some cases you can get useable information without even knowing exactly what your problem was! Don't take my word for it, look up "blind deconvolution" in your favorite image processing textbook or just use google.
If you're an IEEE member there is an interesting tutorial entitled "Image Deblurring: I Can See Clearly Now" by James Nagy and Dianne O'Leary. In addition to this a real world applications in motion deblurring can be seen here http://www1.cs.columbia.edu/CAVE/research/demos/n
The problem may not be identical to NASA's problem but the mathematical deconvolution techniques are the same.
I realize you just want some attention but a small sense of disbelief is in order since many new developments in the sciences are pretty indistinguishable from magic at first glance.
How does this math work? All the article really tells me is that its math.
They also claim "deconvolution" can improve the resolution of a good telescope. Why? Wheres the extra data come from?
what the heck is this?
Why stick up for big business?
Years ago I tried to warn people that Tempel 1 was an alien monitoring post, and that it we needed to study it to discover their origins so we could be vigilant for their return. I was locked up for years. Now that I've escaped I find that they're smashing a rocket into it! While this at least proves I wasn't crazy, it's not going to help anything. Any civilization that has the technology to maintain a link to an outpost in a remote star system without it being detected by civilian scientists probably has the ability to defend itself against what it would probably perceive as aggression. While I'd like to believe that their advances have made them peaceful and even merciful, recent events on Earth suggest that the best we can hope for is millenia of enslavement.
There's no failure quite as dissatisfying as a complete and total solution to the wrong problem.
"The table-sized, 820-pound (372-kilogram) impactor is scheduled to smash into the comet's nucleus at 23,000 mph (37,000 kilometers) per hour"
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
enhance...enhance...
"We will alter images to make them clear"
-NASA
My answer: no WAY! Really?
After spending the millions and waiting for years, isnt it a LITTLE apparent that work will be done on images to make them clear? Does it require a press conference to announce the very apparent?
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
They're always able to make blurry photographs sharp, and it only takes about 10 seconds...
-- Andyvan
Oh give it up. This is so OLD. I've seen this "picture enhancement" being used in the movies all the time. You know, when there's this blurry picture and then suddenly it's "enhanced" and is crystal-clear?
Or on that Alias documentary where the CIA didn't have an audio feed so they had this program that would decipher words by lip reading at this obscene angle from a camera on the ceiling?? This stuff is so easy these days...
You'd think NASA would have this down pat... Maybe it's the budget cuts...
Would you believe that I was too lazy to find a more appropriate thread?
Oops I fell for it again.
Lima Oscar Lime, Mike Alpha Tango Echo
I found that if you take the film out of the camera after the picture is taken, and then either blow on it or flop the picture back and forth irt will make it develop far quicker and much clearer.
Maybe we could get some of the aliens from area 51 to hitchhike onboard and take care of that for us!
Like arts? Like cheesy little Indie mags? Check out www.artwerkmag.com, and don't laugh at the bad coding please.
Maybe he meant math-emetical, ie vomiting in the proximity of math...
Seven puppies were harmed during the making of this post.
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How did this get a -1 rating? It should be modded informative or at least funny.
<<<
I once moved my mouse a bit and gave a - rather than a +. SH. The metamoderators seem to have taken care of it both times.
Gotta be careful about that. There are metamoderators who label any negative mod as 'unfair'. I went troll bashing with my mod points a couple of times. Lost all my karma and didn't get mod points for months.
Karma bonus=off
1000 SlashDot sigs
PS: As others pointed out, deconvolution (which is the process used here) is not a new concept. Far from it, in fact.
That's probably not quite "deconvolution"; it's probably high-pass filtering in Fourier frequency space...to deconvolve, you have to have a proper kernel to "deconvolve" with, which Photoshop has no knowledge of.
Not that it makes sense to many of you...
Will NASA be allowed to use a calculator to solve the math problem?
NASA announced that they believe they have a solution for the Deep Impact mission's blurry vision problem: math.
Augh! That's their solution to everything!!
Umm.. The blur can be estimated from the data. It's not trivial but it is done all the time. There are tonnes of techniques, iterative and otherwise, that given a some prior information (which I am sure there is a fair bit of, given that they have a good idea of the optics and sensors involved) can get you a pretty good estimate of the blur.
Deblurring is essentially a convolution operation anyhow. Its (DE)convolution since they want to reverse the original convolution of the original scene that occured due to convolution with the blur kernel.
-mp-
A bunch of profs and students at Georgia Tech got involved and were able to get very decent results. There's an oft used image of saturn with a part of the rings showing (I think it's in the Matlab test images set) that they worked on.
-mp-
Math guys of the world, unite!
;-)
(Anybody wanna hire me?)
Yes -- I do know what you're talking about.
After all, I am strangely colored.
If NASA is being at all inovative with their anti-blur technology, it would be cool to see it integrated into existing sharpen tools in gimp or picassa.
or else!
One way to fix the injustice is to post in the thread. *Poof* Your mod disappears. Of course, so does one of your mod points, but better than leaving a divot in someone's karma, eh?
You can't talk about Wikipedia's flaws on Wikipedia
I worry when people say things like "mathematics solved problem X", because people often think of pure mathematicians and mathematics departments.
Deconvolution was pioneered by mathematicians like Wiener nearly a century ago, but academic fields have shifted and split since then. These days, this kind of work would more likely be carried out in an applied math, electrical engineering, statistics, or computer science department than a pure mathematics department (some mathematics departments cover applied math, while others don't).
Both pure and applied mathematics are important fields of study, but both the approaches and the day-to-day work are very different. If you are a student, think about this and choose carefully.
Nah, simple sharpening kernels like PS does are quicker and easier to apply the spatial domain. Frequency space is overkill.
If they're convolving kernels (being a 1-d signals guy and never working with images, I have no idea if they are) it's pretty likely that it's faster to perform the sharpening in frequency space, where it becomes a multiplication operation instead of an integration operation.
I'd really recommend reading about Kalman filters, rather than Wiener; they're more broadly applicable, as they don't require a stationary system (though they still want white Gaussian noise). In addition, they have the nice benefit of not requiring any time-frequency transformations.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
You can try this at home with the Gimp: Refocus.
-- Ed Avis ed@membled.com
First of all, blurring is not a fully reversible process. If you convolute two signals, the smoothness of the convolution is essentially the smoothness of the smoothest signal ( can you say that rapidly ? ). Smoothing means convoluting with a smooth kernel, for exemple a gaussian (gaussian blurring). If you deconvolute it you will sharpen the image but keep the smoothness so information IS lost.
Now it can give good results... the most common deconvulting filter is <a href="http://en.wikipedia.org/wiki/Wiener_filter>
Wiener filtering</a> but I suspect they can come up with some more efficient non linear filter.
Now the question is, if deblurring can be performed with deconvolution, how can my brain not learn to do it ! After all, my eyes are just unfocused so the compensation created by my lenses could be performed by my brain...
\u262D = \u5350
You know in films when they get a really burry satellite image, and some hero guy goes "can we enhaance thaaat?". So some geek clicks a button and it goes a lot sharper, and you're thinking, "if only that worked in real life". Well it does and you can try it yourself. Here is some free software that allows you to have a play and "enhance" all those blurry pics you have lying around.
I've tried this myself and it works quite well. I tried it on a picture I took of the moon with a 400mm lens and it made quite an impressive difference.
> There are metamoderators who label any negative mod as 'unfair'. I went troll
> bashing with my mod points a couple of times. Lost all my karma and didn't get
> mod points for months.
You can metamod too, and it's a good way of getting modpoints (according to the docs).
I rememeber reading a book about hubble, where the author went into some detail about de-convolving the images. They got very excited by some odd ring like structures that seemed to be around distant, bright features.
Prior to the installation, there was some discussion about whether the cost of COSTAR was worth it, because the de-convolution was working so well. It was already showing things they had never seen before.
When COSTAR was installed, these structures dissappeared...
Opinions vary on the author of course, but the stories he tells are interesting to read.
-- it's ridiculous how many people misspell ridiculous... (damn, damn, damn...)
Actually there were whole SPIE conference tracks on the Hubble problem for a while.
If I remember correctly they didn't account for the bow in the lens caused by gravity. So technically it was a miscalculation that lead to a manufacturing problem.
I have great faith in fools - self confidence my friends call it. - Edgar Allan Poe
Is the idea of finding math. :) I love the article summary that makes it sound like NASA just sort of lobbed the thing into space, found it had blurry vision, and started looking an old drawer in the corner of the lab: "History. Nope, not helpful. Biology? Nope, no use. Psychology? We'd better send that one to the public relations dept. Math. Hey, that might be a good idea..."
That is not math. It is digital signal processing. Math is about proofs of theorems. Digital signal processing is what the name describes ;) I hate it when they won't give credit for the field that really researches these problems.
You know, there's one thing I hate even more than popups:
Websites that try to auto-download their software when you visit their page. In a meta-refresh tag, nonetheless.
Asshats.
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
I'll have to look into Kalman filters. I knew when I posted that someone was probably going to call me on the Wiener filters since I knew there were better - they were just the first example that I could think of off the top of my head at 2 AM. I'm not familiar with Kalman though.
Oh. I thought it said METH to Crack... And the headline still made sense.
You never really know how close to the edge you can go until you fall off.
I'd wonder if it's really any more efficient to do that direct convolution than the time-frequency transforms for large images, but again - 1D guy, 2D FFTs sort of confuse me and I definitely don't have an idea how much work is required to perform the DFT on an image of size MxN.
Kalman eliminates the necessity of doing anything in the frequency domain, as it's purely a state-space method. Still requires linearity, still requires white Gaussian noise, but it provides the provable best linear unbiased estimate (BLUE) for the systems it applies to, which is a reasonably broad class. It's a neat technique for providing a denoised estimate from a noisy signal. A lot of the literature on Kalman filtering is from control theory, as that's really where it was developed, although its seen a lot of use in the past couple decades in other signal processing domains.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
I once moved my mouse ... taken care of it both times.
The only thing better than only making a mistake once is when you get it corrected twice...
You are collecting data, with a camera. Now your camera is somehow flawed for whatever reason. So your data collection process has a degree of error.
This systematic error can be estimated with only passive observation. Start by taking the Fourier transform of the image to see where it lacks in the high spatial frequencies, and then boost those frequencies until you get an image that looks justifiable. The process is similar to that of using an equalizer on audio.
So we're working with an "estimate" of what the data "should" be, and not what the data really IS.
An estimate can still be useful. The point is not to make "perfect" images but instead to make the most useful images within budget.
I definitely don't have an idea how much work is required to perform the DFT on an image of size MxN.
Discrete Fourier transform is a separable operation. Do FFT on all the rows and FFT on all the columns in O(MN log N + NM log M) time.
Whether you do your convolution in the spatial/time domain (X convolve F) or in the frequency domain (iFFT(FFT(X) * FFT(F))) depends on the size of F and whether F is separable. In many cases, the convolution kernel is small enough that the time of doing forward and inverse Fourier transforms on the whole image outweighs the cost of doing convolutions through integration, especially if the kernel is separable. (A separable kernel can be factored into row_kernel convolve column_kernel.) In other cases, the kernel is large and not separable, and doing the convolution in the frequency domain might prove reasonable.
linear unbiased estimate (BLUE)
Is there a reason that the letters of the acronym are out of order?
Is there a reason that the letters of the acronym are out of order?
They're not.
Best Linear Unbiased Estimate.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)