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Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

theregister.co.uk

11–20 of 128 posts

Re: Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

#11
post #8

I would imagine that in the future video encoders will start to automatically include a cryptographic signature every X frames, which then players will become aware of and show an indicator for "original / modified" content.

It'd be too easy to fake, just replace the sensor in an approved camera with your own data feed.

And that's assuming it wouldn't be somewhat trivial to dump keys from one or more cameras on the market to create a an easy tool or resignvideo.com... which is a massive assumption.

As the movie industry has already seen, cryptography doesn't help you when you push out the keys to everyone. It'd be about as effective as DRM is at stopping video piracy.

Re: Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

#13
post #8

I would imagine that in the future video encoders will start to automatically include a cryptographic signature every X frames, which then players will become aware of and show an indicator for "original / modified" content.

That wouldn't stop from someone filming a fake video.

Re: Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

#14
post #11
post #8

I would imagine that in the future video encoders will start to automatically include a cryptographic signature every X frames, which then players will become aware of and show an indicator for "original / modified" content.

It'd be too easy to fake, just replace the sensor in an approved camera with your own data feed. And that's assuming it wouldn't be somewhat trivial to dump keys from one or more cameras on the market to create a an easy tool or resignvideo.com... which is a massive assumption. As the movie industry has already seen, cryptography doesn't help you when you push out the keys to everyone. It'd be about as effective as D…

You could go on the level of Apple - hardware security chip with presigned bootloader + a chain of trust to boot the OS, and the private key stored in a secure enclave. Then generate a cert for every second of video or so and embed it into the media format. Don’t sign the video if you detect any foreign hardware.

Re: Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

#15
post #11

Earlier quoted context omitted.

It'd be too easy to fake, just replace the sensor in an approved camera with your own data feed. And that's assuming it wouldn't be somewhat trivial to dump keys from one or more cameras on the market to create a an easy tool or resignvideo.com... which is a massive assumption. As the movie industry has already seen, cryptography doesn't help you when you push out the keys to everyone. It'd be about as effective as D…

You could go on the level of Apple - hardware security chip with presigned bootloader + a chain of trust to boot the OS, and the private key stored in a secure enclave. Then generate a cert for every second of video or so and embed it into the media format. Don’t sign the video if you detect any foreign hardware.

You could try but it'd still be possible to just fake it at the sensor level, essentially so the IC would see your video as the analog signal coming in and encode it as if it were any other image. It's basically the "analog hole" of the video world.

If you wanted to do the cheap version of this you could probably set up a screen with proper lighting such that it'd line up well enough that screen and sensor pixels matched closely making it near if not completely impossible to tell a screen was involved.

Worse, such a signature on a fake video may give people false confidence in it being real, when really it still needs scrutiny especially if a possible state level or dedicated attacker is involved.

Re: Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

#16
post #8

I would imagine that in the future video encoders will start to automatically include a cryptographic signature every X frames, which then players will become aware of and show an indicator for "original / modified" content.

I'm thinking that we'd need an Originality Authority (like a CA), to act as the anchor. I assume anyone could just strip the cryptographic signature and then re-sign it with their own signature, and we'd need an authority to prevent that. Upload your content, request a key you can sign with, the OA checks against previously registered content in it's database for originality (I can only assume this would be as buggy…

If everyday people are allowed to possess hardware that can sign images, it would only require someone feeding the fake images into the sensor that would be recording. Then, they would have a verified yet still fake image, which if anything would lead to more people falling for it. You could require that information about the recording also be included (gps, timestamp, etc.) but not only does that harm privacy, it means that when someone fakes it then people will trust the fake even more.

Re: Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

#19
post #15

Earlier quoted context omitted.

You could go on the level of Apple - hardware security chip with presigned bootloader + a chain of trust to boot the OS, and the private key stored in a secure enclave. Then generate a cert for every second of video or so and embed it into the media format. Don’t sign the video if you detect any foreign hardware.

You could try but it'd still be possible to just fake it at the sensor level, essentially so the IC would see your video as the analog signal coming in and encode it as if it were any other image. It's basically the "analog hole" of the video world. If you wanted to do the cheap version of this you could probably set up a screen with proper lighting such that it'd line up well enough that screen and sensor pixels mat…

Nikon’s been offering chip-based video crypto for years, it’s just not popular in consumer-grade hardware yet. If it was, we’d all be up in arms about our devices having a unique fingerprint in every photo (or video) that could be used to track us.

Re: Ctrl Shift Face: A growing ‘deepfakes’ YouTube channel

#20
Articles like these make me eager for advances made in the 'authenticity' market. I recently learned of a company called Truepic[0] that specializes in photo and video verification.

From the New Yorker article I read:

"Truepic, a startup in San Diego, aims at producing a new kind of photograph—a verifiable digital original. Photographs taken with its smartphone app are uploaded to its servers, where they enter a kind of cryptographic lockbox. “We make sure the image hasn’t been manipulated in transit,” Jeffrey McGregor, the company’s C.E.O., explained. “We look at geolocation data, at the nearby cell towers, at the barometric-pressure sensor on the phone, and verify that everything matches. We run the photo through a bunch of computer-vision tests.” If the image passes muster, it’s entered into the Bitcoin and Ethereum blockchain. From then on, it can be shared on a special Web page that verifies its authenticity. Today, Truepic’s biggest clients are insurance companies, which allow policyholders to take verified photographs of their flooded basements or broken windshields. The software has also been used by N.G.O.s to document human-rights violations, and by workers at a construction company in Kazakhstan, who take “verified selfies” as a means of clocking in and out. “Our goal is to expand into industries where there’s a ‘trust gap,’ ” McGregor said: property rentals, online dating. Eventually, he hopes to integrate his software into camera components, so that “verification can begin the moment photons enter the lens.” [1]

[0] https://truepic.com/

[1] https://www.newyorker.com/magazine/2018/11/12/in-the-age-of-...

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