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A comment on Photoshop 'unblur' leaves MAX audience gasping for air. Parent comment

Re:Photoshop 'unblur' leaves MAX audience gasping for air by wickedchicken on Tuesday October 11, 2011 @03:31AM (#3097584)
One key problem with deconvolution is it's very susceptible to noise. I'm guessing they developed a way to ramp up the coefficients so you see an increase in clarity while keeping the noise below visible levels. So much of image (and audio!) processing is about getting away with noise the person can't detect :)

On a side note: does anybody know of workable deconvolution algorithms that vary the kernel over the image? The example would be compensating for a bad lens.

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Re:Photoshop 'unblur' leaves MAX audience gasping for air by elithrar on Tuesday October 11, 2011 @05:10AM (#3097818)
> So much of image (and audio!) processing is about getting away with noise the person can't detect :)

Adobe's noise processing algorithms in their software are something else, especially in ACR6/Lightroom 3.

I moved 'down' from a 5D2 to a Panasonic GF1 as I don't shoot pro anymore, and ISO1600 on this thing with a slightly-off exposure can be pretty noisy. Lightroom cleans it up incredibly well without losing clarity/sharpness. Before that, I'd just do all I could to keep the ISO down so I didn't 'lose' images to noise.

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Re:Photoshop 'unblur' leaves MAX audience gasping for air by dpe82 on Tuesday October 11, 2011 @06:37AM (#3098022)
It's a very different kind of noise. Artifacts, is what he meant to write. Motion deconvolution done wrong tends to lead to things like ring artifacts and other things that look like the image has been really badly and inaccurately oversharpened.

The basic theory for doing this type of deblurring isn't too bad, but making it easy and automatic becomes a really difficult computer vision-related problem. Adobe has been working on this (and a lot of other pretty cool stuff) for quite a while. It'll be interesting if they ever ship it.

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Re:Photoshop 'unblur' leaves MAX audience gasping for air by dhimes on Tuesday October 11, 2011 @08:20AM (#3098237)
I'm guessing that there is a whole lot of analysis left out by loading pre-configured coesfficient files to deconvolve these images. Getting that process to be relatively easy for the lay-person will be a challenge.
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Re:Photoshop 'unblur' leaves MAX audience gasping for air by DanBC on Tuesday October 11, 2011 @05:07AM (#3097810)
The early Hubble images were fixed, maybe there's something around for those?

(http://adsabs.harvard.edu/full/1992ASPC...25..226K)

What an awful URL.

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Re:Photoshop 'unblur' leaves MAX audience gasping for air by martinkallstrom on Tuesday October 11, 2011 @03:09PM (#3099882)
Just 10 minutes ago I put my daughters to bed and I told them about Hubble. I realized myself how incredible it is that we humans have dragged what is basically a huge camera out in space just so we can shoot pictures of the stars without lots of air being in the way. I promised them we would Google for Hubble photos tomorrow.

Sorry for OT, was just happy to see the coincidental link to a Hubble photograph.

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Re:Photoshop 'unblur' leaves MAX audience gasping for air by wisty on Tuesday October 11, 2011 @05:13AM (#3097822)
>> So much of image (and audio!) processing is about getting away with noise the person can't detect

For example, if you see what looks like blurry skin, and you de-blur it into skin, no-one will complain. Unless your de-blur noise elimination thinks the blurry eyes are noise, and turns the subject into a faceless monster.

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Re:Photoshop 'unblur' leaves MAX audience gasping for air by pork on Tuesday October 11, 2011 @04:14AM (#3097693)
Thats just a different kind of kernel applied to the whole image.
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