Recovering Real Faces from Face-Generation ML System

New paper: “This Person (Probably) Exists. Identity Membership Attacks Against GAN Generated Faces.

Abstract: Recently, generative adversarial networks (GANs) have achieved stunning realism, fooling even human observers. Indeed, the popular tongue-in-cheek website http://thispersondoesnotexist.com, taunts users with GAN generated images that seem too real to believe. On the other hand, GANs do leak information about their training data, as evidenced by membership attacks recently demonstrated in the literature. In this work, we challenge the assumption that GAN faces really are novel creations, by constructing a successful membership attack of a new kind. Unlike previous works, our attack can accurately discern samples sharing the same identity as training samples without being the same samples. We demonstrate the interest of our attack across several popular face datasets and GAN training procedures. Notably, we show that even in the presence of significant dataset diversity, an over represented person can pose a privacy concern.

News article. Slashdot post.

Posted on October 14, 2021 at 9:56 AM9 Comments

Comments

Jeff October 14, 2021 2:02 PM

I’m not sure if this is a weakness in the generation algorithm, or just that website. But I have yet to see ThisPersonDoesNotExist generate someone ugly. Compare the ratio of pretty to ugly faces on the street or at a mall with that site. I think there’s a built-in bias somewhere.

bill October 14, 2021 2:40 PM

After reloading to see a lot of samples from ThisPersonDoesNotExist, I noticed that sometimes eyeglasses and hats and other objects near the face can produce some strange effects. One young woman probably had a blue baseball cap on backwards. The strap was distorted and she ended up with blobs of blue in her hair.

Peter A. October 15, 2021 3:27 AM

@Jeff: good observation. They’ve apparently trained on photos scraped from the ‘net, and virtually nobody posts ugly photos of themselves.

@bill: Yes, often the faces have subtle distortions. The background is weird almost every time. I have noticed disproportionate amount of asymmetric ears. Sometimes there’s an unnatural smudge somewhere on the face, sometimes a stray strand of hair in a strange place, sometimes there’s something uncanny with the teeth etc. They’re not perfect, but if you manually photoshop them, these pictures could be a good start for a fake identity.

BTW. there are sister pages about nonexistent cats (okayish), horses (pretty bad, often generates lame beasts) and chemical compounds (IMO pointless, maybe as an exercise; and you’ll never know when someone finds a way to synthetize them anyway)

Peter October 15, 2021 4:18 AM

Just a thought: I wonder what would have happened if they trained the algorithm on NatGeo-like photos of people from distant and poor corners of the world, which are, for the popular Western standard, not pretty. The result could be interesting. But maybe the corpus is just too small.

Sut Vachz October 16, 2021 1:24 AM

The faces seem to have the same peculiar and “off” proportion between the modeling of the facial skull and the the eyes, a bit like the same person wearing disguises.

A Nonny Bunny October 16, 2021 3:11 PM

@peter

Just a thought: I wonder what would have happened if they trained the algorithm on NatGeo-like photos of people from distant and poor corners of the world, which are, for the popular Western standard, not pretty. The result could be interesting. But maybe the corpus is just too small.

You can train Stylegan-Ada with just a few thousand photos and get pretty good results in a few days of training (on a fairly modest GPU).
The biggest problem is probably finding good photos. You need a good resolution, and ideally faces looking straight toward you (and the fewer distracting backgrounds and objects the better). Aligning and cropping faces can probably be done automatically with face detection.

Matt October 17, 2021 2:36 AM

The paper focuses on privacy but I think of equal importance are the implications for intellectual property. Companies will inevitably claim ownership rights to generated faces and such. Whether or not a computer generated actor is an original work with respect to copyright could be a multi-million dollar question.

Clive Robinson October 17, 2021 5:07 AM

@ Matt, ALL,

Whether or not a computer generated actor is an original work with respect to copyright could be a multi-million dollar question.

Which takes us into the domain of “Non Fungible Tokens”(NFTs) which are based on the “blockchain” and all the horrendous issues that brings up.

msb October 19, 2021 12:04 PM

It’s been a while since I’ve done a deep dive into copyright, but algorithmically generated content was explicitly excepted from copyright protections, at least in the US and Canada. I believe some EU (and former EU) countries have recently granted explicit inclusions to the creator of the algorithms, although there is some debate about whether that would include AI generated content, since the algorithm is actually generated by an algorithm.

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