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A new way to detect ‘deepfake’ picture editing

lightbluetouchpaper.org

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Re: A new way to detect ‘deepfake’ picture editing

#71

Post by barbazoo »

Extigy wrote: post #52
mojomark wrote: post #48

Couldn't reputable photo/video authors just publish content as an NFT? If the NFT is not traced back to a reputable source, then the content is deemed unreliable.

Why not just sign the content with a digital signature?

You mean devices could sign the images they create and then wherever someone publishes the picture you'd be able to validate the signature using that device's (published somewhere) public key? That would be cool indeed.

Except it wouldn't change anything. Facebook doesn't care about fakes and people wouldn't care whether the picture someone shared hasn't been tampered. Also whoever manipulated the picture could just sign it again probably.

Re: A new way to detect ‘deepfake’ picture editing

#72

Post by this_was_posted »

Extigy wrote: post #52
mojomark wrote: post #48

Couldn't reputable photo/video authors just publish content as an NFT? If the NFT is not traced back to a reputable source, then the content is deemed unreliable.

Why not just sign the content with a digital signature?

Because then you would lose in the buzzword bingo game.

Re: A new way to detect ‘deepfake’ picture editing

#74

Post by sigmoid10 »

arbitrage wrote: post #61
sigmoid10 wrote: post #36

Earlier quoted context omitted.

A few weeks ago, there was a post here about that guy who deepfaked female profile pictures. He showed that the visible artifacts go away by merely scaling up the number of parameters in the model. Give it a few years and these fake images will be impossible to detect unless we agree on some way of cryptographically signing images from real cameras.

define 'real camera', please.

Nothing stops smartphone or camera manufacturers from adding something like a TPM to the CMOS. In fact, Apple already does sign its hardware components to prevent third party repairs.

Re: A new way to detect ‘deepfake’ picture editing

#76

Post by godelski »

roywiggins wrote: post #60
spywaregorilla wrote: post #58

Earlier quoted context omitted.

At best that would allow you to tell if a picture was raw footage. Which is pointless because people edit things all the time.

I guess there'd have to be certified editors, which would be trusted to allow only "safe" operations on images (crop, white balance, levels, etc) and would sign the resulting jpegs themselves alongside the signature from the camera. It doesn't really seem likely at all to work in practice.

Editors include deep fake technology now. Removing people from a scene has been a common technique for a long time and generative models just have made this easier (e.g. usage: you want the background/scenery but it is a well traveled tourist destination so you can't get a photo without people in it.[0])

[0] Normally you accomplish this by taking several photos and combining them

Re: A new way to detect ‘deepfake’ picture editing

#77

Post by godelski »

spywaregorilla wrote: post #64
roywiggins wrote: post #60

Earlier quoted context omitted.

I guess there'd have to be certified editors, which would be trusted to allow only "safe" operations on images (crop, white balance, levels, etc) and would sign the resulting jpegs themselves alongside the signature from the camera. It doesn't really seem likely at all to work in practice.

I want to see an ai that changes picture A to picture B by abusing rounding errors in white balance and levels adjustments.

It isn't exactly what you're looking for, but along the same vein are things called diffusion models.[0]

[0] https://lilianweng.github.io/lil-log/2021/07/11/diffusion-mo...

Re: A new way to detect ‘deepfake’ picture editing

#78

Post by telchar »

spywaregorilla wrote: post #58
sigmoid10 wrote: post #36

Earlier quoted context omitted.

A few weeks ago, there was a post here about that guy who deepfaked female profile pictures. He showed that the visible artifacts go away by merely scaling up the number of parameters in the model. Give it a few years and these fake images will be impossible to detect unless we agree on some way of cryptographically signing images from real cameras.

At best that would allow you to tell if a picture was raw footage. Which is pointless because people edit things all the time.

The point is that an image of consequence, if real, would have a signed raw copy available which people could check to verify that there was in fact a real image that showed what a given edited image purported to show. If an image is being circulated but no one as been able to verify that a signed version exists, that image remains untrustworthy. This wouldn't stop people from editing images for aesthetic value.

Re: A new way to detect ‘deepfake’ picture editing

#79

Post by lifeisstillgood »

sebzim4500 wrote: post #56
sigmoid10 wrote: post #49

Earlier quoted context omitted.

You only need a method of key invalidation and renewal, that's all. Ssl certificates have been facing this problem for years. The threat model is equal to someone infecting millions of devices and then sending back banking data, so it's not like people aren't working on mitigating that stuff.

>Ssl certificates have been facing this problem for years. That's an entirely different, and much easier problem. In the case of SSL you are not worried about an attacker obtaining a certificate for any host, just the ones you care about. E.g. an attacker getting a certificate for facebook.com would be catastrophic, but an attacker getting a certificate for a website that no one uses would be a non-issue. For the cas…

Surely the threat model remains the same. being able to forge photos from a camera held by the LAPD forensics lab, or Reuters would be more "damaging" than having my camera hardware key.

I think there is scope for a simple self regulation here to start us off. I would love to see Reuters or the BBC start to publish their raw footage with the hashes. It is a question of starting the ball rolling

Re: A new way to detect ‘deepfake’ picture editing

#80

Post by kkielhofner »

smaryjerry wrote: post #63
sigmoid10 wrote: post #36

Earlier quoted context omitted.

A few weeks ago, there was a post here about that guy who deepfaked female profile pictures. He showed that the visible artifacts go away by merely scaling up the number of parameters in the model. Give it a few years and these fake images will be impossible to detect unless we agree on some way of cryptographically signing images from real cameras.

Imagine a cryptocurrency like log of data verifying images. Essentially, all cameras will be internet connected with a process to force creation of an NFT at the moment users press the photo button which includes the entire data of the image. Any image without that tech will be considered unreliable. Of course that would have implications that no photo could ever be deleted, I’m guessing this system would be governme…

This is exactly what my new startup Tovera[0] does. Process is roughly:

1) Upload image with web-based user dashboard.

2) We strip existing metadata (for privacy and all of the reasons everyone else does).

3) Our API generates a unique identifier for the asset (UUIDv4 in hex).

4) The unique identifier is embedded in the image with XMP.

5) A SHA256 checksum of the entire file is generated.

6) Via the API the checksum is associated with the unique identifier (along with some other stuff).

7) (Optionally) the unique identifier and checksum are added as JSON to IPFS via a pinning service and (essentially) an NFT is minted for the JSON verification data on the Polygon blockchain.

8) The user gets sharable[1] and iframe embeddable[2] links and the ability to post directly to various social media networks, etc.

When the links are viewed our Javascript reads the unique id, fetches the stored checksum from the API, and generates a new checksum of the image in the browser. If the checksums match a clickable icon appears in the top right of the image with additional information about the image, links to the IPFS and blockchain links, etc. Users can change the additional metadata at anytime and it updates instantly.

Long term goals are hosted javascript verification library, browser extensions, mobile SDKs, potential browser/OS integrations, native plugins for popular authoring/editing applications, and so on.

Happy to answer any questions!

[0] https://tovera.com

[1] https://share.tovera.com/preview/c65b0658ab6e4d89963b1e0a319...

[2] https://share.tovera.com/embed/c65b0658ab6e4d89963b1e0a319a1...

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