I doubt this is true. Most videos are likely disseminated from a handful of companies.
> Even if smartphone manufacturers start integrating digital signatures right into their cameras, you can use the smartphone to re-record a pre-recorded fake video. And I'm sure that with enough resources you can do something way more clever.
Even if a fake video was re recorded it would have a different signature than the “original”. Problem solved.
Literally cryptography is the only solution
I assume the intent is not to store solely a direct hash of the original video, but also the original file which can be fingerprinted, or the fingerprint itself that will be matched if a later duplicate is uploaded.
Fingerprint differing from hashing in that two non-identical, but similar files (e.g. an original video and deepfake) can have the same fingerprint, but differing checksums.
Even if smartphone manufacturers start integrating digital signatures right into their cameras, you can use the smartphone to re-record a pre-recorded fake video. And I'm sure that with enough resources you can do something way more clever.
I really don't see how crypto can solve this problem. I don't think AI can either (for reasons already mentioned in this thread). It's something we'll have to learn to live with.