Deterministic beats probable

The limit of detection

Detectors ask whether a file looks generated. At scale, even a small error rate flags genuine files every day, and the review queue never clears. More data does not fix it: new models keep outpacing detectors trained on older ones.

Proof at the source

The alternative is to answer a different question: where did this file come from? That answer can be sealed when the file is made:

• A C2PA manifest signs the origin, the time and the creator.
• An invisible watermark survives the re-encoding that strips metadata.
• A perceptual fingerprint finds the file again when the metadata is gone.

The certificate either verifies or it does not, and anyone can check it without an account. Detection stays useful for files that arrive with no provenance at all. For everything else, proof beats probability. Adapted from the Shield journal.