How long before it becomes a plausible criminal defence to say “the CCTV must have been deepfaked, that’s not me”?
The indicator of reliability will be the chain of custody of the video data.
That's not to say it shouldn't be researched, or people more creative than me won't think of beneficial use cases.
From the abstract: "Our system can generate novel points between professional tennis players that resemble Wimbledon broadcasts, enabling new experiences such as the creation of matchups between players that have not competed in real life, or interactive control of players in the Wimbledon final."
I don't believe academic researchers needs to justify their work by providing real life applications. But if that were the extent of deepfake's utility, I'd be underwhelmed.
I recently lost my dog. The idea of interacting with a virtual model of her to help ease the grief is interesting and scary, and ripped straight from a Black Mirror episode.
A mother meeting her dead daughter again through VR. It's a video that fills me with all sorts of emotions. It feels so wrong but at the same time it is very touching and beautiful.
Assume the secure element is in fact secure, the issue then, as with any public/private key scheme, lies with establishing trust of the keypair. Do you trust the manufacturer that he will not be breached?
And more pressing even; How do you prevent someone modifying their internal camera video stream such that they may send any data to the authentication chip/mechanism?
And if all this is implemented, it can be done even more low level - just direct the camera e.g. to your screen (I assume solutions would then crop up to increase the fidelity of such a solution).
I am not saying such a solution would not provide ANY benefits, I am just pointing out that these issues prevent it from becoming a silver bullet.
Less about the algorithms, but more about designing applications of cryptographic primitives?
However the secret signing key will have to reside inside the camera in a way that a determined attacker cannot extract it. Sounds hard.
So you could still fake videos, but any accusation of tampering could be verified by checking the seal is intact. (of course you need non-forgeable seals too, but that's comparatively easier)
A simpler detection mechanism would be to use stereoscopic (or rather real depth detection) cameras though.