In the days after the US Department of Justice (DOJ) published 3.5 million pages of documents related to the late sex offender Jeffrey Epstein, multiple users on X have asked Grok to “unblur” or remove the black boxes covering the faces of children and women in images that were meant to protect their privacy.
The black boxes would be impossible, but there are some types of blur that keep enough of the original data they can be undone. There was a pedofile that used a swirl to cover his face in pictures and investigators were able to unswirl the images and identify him.
With how the rest of it has gone it wouldn’t surprise me if someone was incompetent enough to use a reversible one, although I have doubts Grok would do it properly.
Edit: this technique only works for video, but maybe if there are several pictures of the same person all blurred it could be used there too?
https://youtu.be/acKYYwcxpGk
Yeah, but this type of machine learning and diffusion models used in image genAI are almost completely disjoint
Agree with you there. Just pointing out that in theory and with the right technique, some blurring methods can be undone. Grok most certainly is the wrong tool for the job.
Several years ago, authorities were searching the world for a guy who had been going around the world, molesting children, photographing them, and distributing them on the Internet. He was often in the photos, but he had chosen to use some sort of swirl blur on his face to hide it. The authorities just “unswirled” it, and there was his face, in all those photos of abused children.
They caught him soon after.
A swirl is a distortion that is non-destructive. Am anonymity blur averages out pixels over a wide area in a repetitive manner, which destroys information. Would it be possible to reverse? Maybe a little bit. Maybe one pixel out of every %, but there wouldn’t be any way to prove the accuracy of that pixel and there would be massive gaps in information.
Swirl is destfuctive like almost everything in raster graphics with recompressing, but unswirling it back makes a good approximation in somehow reduced quality. If the program or a code of effect is known, e.g. they did it in Photoshop, you just drag a slider to the opposite side. Coming to think of it, it could be a nice puzzle in an adventure game or one another kind of captcha.
You’re right. I meant more by “non-destructive” that it is, depending on factors like intensity and known algorithm, reversible.
This is true that some blurs could be undone, but the ones used in the files are definitely destructive and cannot be undone. Grok and any other image generation tool is also definitely not capable of doing it. It requires knowledge of how it was blurred so you can use the same algorithm to undo it, models simply guess what it should look like.