Content Credentials
Also called: C2PA
Cryptographically signed metadata recording how a piece of media was created and edited.
Content Credentials, built on the C2PA standard, attach a tamper-evident history to a file — captured by this camera, edited here, generated by that model. The approach proves provenance rather than detecting fakes, which is a more tractable problem. Its weakness is that stripping the metadata is trivial, so absence proves nothing.
In practice: An image whose credentials show it came from a camera, not a generator.