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Photoshop 'unblur' leaves MAX audience gasping for air

9to5mac.com

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Re: Photoshop 'unblur' leaves MAX audience gasping for air

#11

Post by klodolph »

nethsix wrote: post #5

I suppose this is more of image sharpening rather than reconstruction. Is this very different from technology on cameras/phones that tries to reduce of photo blurness due to unsteady hands?

What makes you suppose that? On an abstract level, you can model blur and camera shake with a convolution kernel. You can then invert the kernel and get back the original image. As an analogy, imagine that someone gives you an audio file with an echo. You can subtract the echo with a filter. Camera shake is harder because of the extra dimension. (Of course, you only get back the exact original in the world of mathematics)

Re: Photoshop 'unblur' leaves MAX audience gasping for air

#13

Post by klodolph »

po wrote: post #3

Does this work with just motion blur or also with aperture blur? It seems like they are calculating the motion of the camera so perhaps just the former.

Defocus (or "aperture blur") cannot be corrected by the methods they mention in the video. However, there are other kinds of blur you can correct.

Re: Photoshop 'unblur' leaves MAX audience gasping for air

#15

Post by jczhang »

dlsspy wrote: post #8

Let me load the specially constructed set of parameters specific to this image so that when I do the next step you get a really clear image. That was a little too hand-wavy. I'm a little dubious until I see what went into that phase.

He used the same parameter profile each time.

Re: Photoshop 'unblur' leaves MAX audience gasping for air

#17

Post by cubicle67 »

benwerd wrote: post #2

Forensic police drama writers everywhere: vindicated. This is seriously cool technology.

not really, because it's not the same thing

what CSI does it add information that wasn't initially there whereas what this is doing is just unscrambling the information. This is only for photos where the camera has moved during exposure, so should be great for low light shots (indoors etc) where you need a shutter speed a bit slower than optimal, say 1/5 second

Re: Photoshop 'unblur' leaves MAX audience gasping for air

#18

Post by chrislo »

I believe the speaker mentioned this algorithm was based on the Point Spread Function[1] but modified to model the movement of the point in time. Dougherty has[2] a static PSF deconvolution implementation that is fun to play with.

[1] http://en.wikipedia.org/wiki/Point_spread_function [2] http://www.optinav.com/Iterative-Deconvolution.htm

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