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There have been third party programs doing this for nearly a decade. This is also the "trick" behind the light field camera. You simultaneously capture multiple versions of a scene, back out the distance information based on depth of field effects (diameter of the point spread functions at each location in each image), then use all that to reconstruct what the photo would have looked like with the focus at a plane of your choosing.

Very handy for macro photos and microscopy where narrow depth of field frequently makes it impossible to get more than a tiny sliver of the subject in focus. Long-term, I predict this is going to replace the bulky "professional" lenses carried by many DSLR photographers. One of the primary reasons to use these large lenses is to narrow the field of view to isolate the subject (blur the background and foreground). You can accomplish the same thing with a smaller lens, a light field camera, and some number crunching. (The other primary reason is for speed in low-light situations, which is becoming less important over time as CCD and CMOS sensitivity constantly improves).

Yeah, this is standard math. A completely out-of-focus picture actually contains nearly as much information as a sharp photo, it's just smeared with a reversible mathematical transform called a point spread function. Reverse it and you get the in-focus image back. There have been third party programs to do this for about a decade. The main problems have been processing speed (it could take a half hour or more a decade ago), determining the point spread function (you have both focus and camera shake, and the former can make figuring out the latter really hard), lens/sensor defects and image format compression (the PSF you calculate for a local region may not work well for the entire picture), and boundary conditions.

The rudimentary 3D info can be used for improving all sorts of scans.

How about...

- Flattening a scan of a book (by the spine)
- Focusing an area that's raised (products like Focus magic assume a section is all out of focus at the same level, whereas a map of the amount of lost focus is possible here).
- Using the above, scanning non-flat items.
- Scanning nearly-flat 3d surfaces.

Add a lens that can vary focus (based on the light differential) and you'd have a good 3D scanner for one side of a mostly-flat item, and a flatbed scanner that wouldn't lose focus on slightly-raised papers.

1. Focus Magic can unblur stuff like you wouldn't believe.
http://www.focusmagic.com/index.htm

I found out about it when some guy from Canon put up a blurred photo of the 5D Mk II, and someone /else/ unblurred it to show the "5D". That freaked him out, and he suggested that Canon integrate the software into the camera itself...

2. change all redacted words to 3 chars, before black-boxing 'em ( in audio, replace all redacted portions with 1 sec of digital silence, and if there's no background noise that gives away the real duration, you should be good to go ).

There:

1 method for unredacting stuff, and 1 method for redacting stuff.

(:

You can't add pixels that aren't there, and an out of focus picture is effectively a lower resolution.

You can, however, apply statistical analysis and AI learning techniques to guess the likely locations of pixels. In that way, you can sharpen a photo somewhat, though it may be inexact. My understanding is that contextual analysis is the next step- if you have pictures of a person and a blurry person, and have more pictures of that person and less-blurry people, you can make predictions about who the fuzzy people are.

I showed this to my PS using friend and he shurgged, said 'Just do a radial blur in the opposite direction' and 30 seconds later had a picture about 80-90% as good as the one they're waving about as being the result of some super secret methodology.
It does strike me as a bit stupid explaining it all - now crims will just use better techniques for blurring themselves out. The media, law enforcement agencies are doing this more and more and it's insane - "we just had an idea for a terrorist attack that might happen and here it is in full", "This is foresnic evidence that allowed us to catch the crim" and so on.

Yup, they spun it (pun intended) into cheap PR. The problem is, it's not that they are super smart, it's that the criminal was super stupid.

And it'll make anyone with basic image processing skills question their overall expertise if they'd brag about untwirl.

That said, the average folk will definitely be impressed. I knew a guy who inverted his photo in attempt to protect his identity (no, he didn't molest children). Imagine his shock when I took the inverted photo, inverted it again arriving at the original.

To him I'm probably some sorta super genius who used sophisticated data restoration hack. To a guy with basic knowledge, it's nothing worth noting.

To see how blur can restore detail not visible to the naked eye, check out Focus Magic. Not as easy as untwirl, but gives you an idea. This is because the blur distribution (usually gaussian if digital, or linear with cameras) gives away the possible origin position of the pixels.

If you pixelize however, with big enough square, you lose real resolution and that's much harder to restore anything interesting out of (it's not like in movies, with the unlimited extrapolation techniques, as we all know).

Other gotchas: covering with black rectangle but leaving it only 1-2% transparent. Looks solid, but data can be recovered.

And a very common other method: people keep leaving their name and camera model in the meta info of the image. Easy to check out via right-click>Properties in Windows.

PS: it was "twirl", not "radial blur" btw.

true, blurring isn't the same as obscuring. That said, a twirl/swirl filter isn't a blur filter either. A twirl/swirl filter relocates pixels from position A to position B. The original pixels are still largely there, you just have to move them back from B to A. That's what Interpol did here - kudos to them for figuring that out. But a blur filter doesn't just relocate pixels - it blends a bunch together. Now don't get me wrong - there's certainly deconvolution methods to reduce blur - especially motion blur - ( one example software: http://www.focusmagic.com/ ) but you're not going to be able to just take any heavily non-motion blurred image and get a supersharp result back. Other techniques, such as pixelization, are even worse to restore - you may as well not try.

-That- having been said.. yes, obscuring does tend to be better.. as long as it's a proper obscuring and not some half-hearted attempt by a news station where an interviewer / whatever has said to want to be inrecognizable, and then you just get a dark silhouette of the person where you can 1. still make out the silhouette, 2. their voice goes unaltered, 3. bump up the brightness enough and you can even make out a face or, in the case of yea olde license plate, a black bar that is supposed to 'track' the license plate properly, but the person applying the bar is a lazy-ass tracker and it 'swims' over the plate, revealing tiny bits of the bottom/top on certain frames - not too much guesswork involved to figure out the proper license plate, as even with multiple possibilities, only one is likely to match the type/color of the car when looked up on the interwebs.

Now then... Let the "what if somebody photoshopped somebody else's head on there first, then applied the filter, now some poor innocent sap is framed!" replies begin.

If you can afford it, get the Nikon 9000. Sell it when you are done. I settled on using an Epson 4990 since I wanted the flatbed for other things. If the difference between a good flatbed and a dedicated film scanner matters to you, then get the dedicated. The film trays that come with the Epson 4990 work pretty well, but I got a better film carrier from http://www.betterscanning.com/ Takes a lot of the hassle out of curled negatives. Also. If you plan to post process your scans much, I highly recommend Photoshop with either NeatImage, http://www.neatimage.com/ or Noise Ninja, http://www.picturecode.com/ for removing noise. FocalBlade or FocusMagic, http://www.focusmagic.com/ has it's place too for some of pictures of interest. Post processing is going to be key in getting the best results from your scanning effort. Figure out what you are willing to live with, because it's unrealistic to scan every negative in at max resolution due to the size of the resulting file.

As mentioned in previous posts, the Digital ICE dust/scratch removal doesn't work on B&W film. Also Kodachrome color slide film may not work well with certain scanners when trying to use the auto dust/scratch removal.

B&W presents some challenges. You must scan at 16 bits/channel resolution, otherwise, B&W results will be too contrasty and lose shadow detail. It sometimes helps to scan as positives then invert the image in Photoshop. Secondly, flatbed scanners tend to be noisy. This can be offset by using a multiple-pass option. Four passes work reasonably well without taking a lot of time. Quite a bit of this noise can be dealt with via NeatImage or Noise Ninja as well. Since Digital ICE (available on the 4990) does not work with B&W, you will get a lot of dust. Resist using third-party dust reduction software since it seriously degrades the image. Just plan to Photoshop images you plan on printing.

If you are wanting to really get down and do some serious negative scanning, quickly (and cost is not restricting). Get a Creo Eversmart (now owned by Kodak) flatbed scanner. http://graphics.kodak.com/global/product/scanners/ professional_scanners/default.htm These are the machines that image archives use when dealing mass volume. It is impractical to drum scan every slide/negative in an archive, and this is an excellent compromise.

The main thing is to make sure your negatives keep protected. In another 10-15 years, the scanning capabilities will be much, much better. However, the people you want to enjoy seeing these scanned images might be gone! So it's best to use what you can and get the job done. Let the next generation scan again if they want it done better.

Anyway, you can do some trickery to achieve higher detail, sort of, by using noise reduction and some intelligent sharpening. I use Neat image and Focus magic, but there are others. Then, if you can shoot RAW, you can upsample to e.g. a 12-mp image, and remove the slight blurriness with Focus magic. In reality you won't get any more detail than was possible to record on an 8-mp sensor, but it will look like you do, because of slight blur in the original from the lens, noise, etc.

I haven't printed such an image yet though, so the actual effect remains to be tested.

No, you can't, and you're completely right about that. But in the out-of-focus picture all the information is (mostly) there, and the question is how to transform that desired subject in focus. If you have the convolution model, you can write an inverse function using Fourier transform. For a quick mathematic formula, see here and scroll a little down until you find section "Wrong lens focus". There's also software that does the trick. The downside here is that it increases the noise as you can see on the focusmagic examples, but nevertheless it's possible and already done. The original work that represents the degradation model is from the 60's.

Yes, and the world is flat.

Let's take a look at a small sample of what Adobe has been doing with Photoshop lately that appeals to professional photographers.

1. Great improvements have been made to the image browser, known as Bridge. Also, many improvements have been made to The Adobe RAW Conversion plugin (known as ACR) . The improvements in these two pieces of the program put it on par with the powerful but buggy Phase One, Capture One What Adobe does that C1 does not is that it integrates flawlessly with Photoshop and it eliminates the puchase of a $500+ piece of software. I've used both and I think Adobe's converter is better, provided a custom calibration is performed with the camera to adjust ACR's color output.

2. Sharpening. Smart sharpen has been added. It does not replace Unsharp Mask (USM), rather is supplements it. It uses complex math to perform something called deconvolution. It can correct small levels of incorrect focus and motion blur. It can also be used as a general sharpening tool. Some photographers will still prefer USM but I like using Smart Sharpen. Previously, one had to buy relatively expensive plugins to do this. The thing is, smart sharpen is better than the best deconvolution plugin available. It allows the operation to be included in actions (similar to macros). It's faster, it can be performed with fractional radii, and it can be turned down in shadows and highlights to avoid needless amplification of noise. One of the few popular deconvolution plugins available, Focus Magic does not have these features. Normally when big companies borrow features only available as add-ons, they are lacking in many areas. Not so in Adobe's case.

These are just a couple of examples of recent Photoshop improvements. There are also lens correction filters, perspective based cloning tools, spot healing tool, and many other features that are NOT considered bloat by many photographers.