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Hacker News Hacker NewsThis isn't actually true. You could do this 20 years ago on a consumer laptop, and you don't need the information you get for free from text moving under a filter either.
What you need is the ability to reproduce the conditions the image was generated and pixelated/blurred under. If the pixel radius only encompasses, say, 4 characters, then you only need to search for those 4 characters first. And then you can proceed to the next few characters represented under the next pixelated block.
You can think of pixelation as a bad hash which is very easy to find a preimage for.
No motion necessary. No AI necessary. No machine learning necessary.
The hard part is recreating the environment though, and AI just means you can skip having that effort and know-how.
I recall a co-worker doing something related(?) for a kind of fun tech demo some ten years or so ago. If I recall it was shooting video while passing a slightly ajar office door. His code reconstructed the full image of the office from the "traveling slit".
I think about that all the time when I find myself in a public bathroom stall.... :-/
1) Open screenshot in MS-Paint (can you even install MS-Paint anymore? Or is it Paint3D now?)
2) Select Color 1: Black
3) Select Color 2: Black
4) Use rectangular selection tool to select piece of text I want to censor.
5) Click the DEL key. The rectangle should now be solid black.
6) Save the screenshot.
As far as I know, AI hasn't figured out a way to de-censor solid black yet.
> The reconstruction of objects from blurry images has a wide range of applications, for instance in astronomy and biomedical imaging. Assuming that the blur is spatially invariant, image blur can be defined as a two-dimensional convolution between true image and a point spread function. Hence, the corresponding deblurring operation is formulated as an inverse problem called deconvolution. Often, not only the true image is unknown, but also the available information about the point spread function is insufficient resulting in an extremely underdetermined blind deconvolution problem. Considering multiple blurred images of the object to be reconstructed, leading to a multiframe blind deconvolution problem, reduces underdeterminedness. To further decrease the number of unknowns, we transfer the multiframe blind deconvolution problem to a compact version based upon [18] where only one point spread function has to be identified.
https://www.mic.uni-luebeck.de/fileadmin/mic/publications/St...
> Moving forward, if I do have sensitive data to hide, I'll place a pure-color mask over the area, instead of a blur or pixelation effect.
Alternately - don't pixelate on a stationary grid when the window moves.
If you want it to look nicer than a color box but without giving away all the extra info when data moves between pixels, pixelate it once and overlay with a static screenshot of that.
For bonus points, you could automate scrambling the pixelation with fake-but-real-looking pixelation. Would be nice if video editing tools had that built in for censoring, knowing that pixelation doesn't work but people will keep thinking it does.
A pixelization filter at least actively removes information from an image, a Gaussian blur or box blurs are straight up invertible by deconvolution and the only reason that doesn't work out of the box is because the blurring is done with low precision (e.g. directly on 8-bit sRGB) or quantized to a low precision format afterwards.
Today we take for granted the ability to conjure a complicated pseudorandom digital stream for keying, but in those days it was just "no can do".
In WWII... SIGSALY was the first system secure by modern standards. Pairs of synchronized one-time phonographic records containing a sequence of tones seeded from a noise source.
In France, public television raised the alarm a few years ago about the anonymization of voices and the blurring of faces of investigative sources. As a result, an anonymization policy has been implemented requiring that voices be replaced by an actor reading the text and that people be filmed from behind at the very least, or even replaced by an actor altogether.
More problematic are the archives of past investigations, which put people like political dissidents and witnesses against organized crime or the mafia at high risk of suffering retaliation. To mitigate this risk, tens of videos have been taken down, and efforts have been made to contact those who may be affected.
https://larevuedesmedias.ina.fr/urgence-france-televisions-i... (in french)
[0] https://groups.google.com/g/alt.video.laserdisc/c/Ws6h9uiumF...
Take that adobe.
I recall interpol doing similar a couple years back to bust a dodgy kids image ring. That was a swirl though which I guess is mathematically easier
maybe this youtube channel will be interesting https://www.youtube.com/@mikirubinstein
so if we could do that 12 years ago, debluring/depixelating of video should be easy