- 01
Fingerprint
SHA-256 · exact bytes
The instant you capture, FactLockCam hashes the exact media bytes. One changed byte produces a different fingerprint.
- 02
Sign
Canonical manifest · owner key
A canonical capture manifest — fingerprint, length, MIME type, UTC metadata, key class — is hashed and signed by your key.
- 03
Anchor
Polygon · public record
When the device is online, the manifest hash is published to Polygon. The transaction is the public reference a later copy is compared with.
04
Verify
Browser · zero upload
A recipient opens factlockcam.com/open, chooses the .flcproof file on their own device, and enters the password. File, signature, and public record are checked as three separate results. Nothing is uploaded.
Read next
- Mechanism Tamper-evident photo and video verification Six stages from capture to recipient check, including what the canonical manifest contains and how the Polygon window is bounded. Read
- Concept What an anchored original is The reference record: exact-file fingerprint, signed manifest, and the optional public transaction that stores its hash. Read
- Explainer How to show a photo was not altered Why an earlier record beats a later argument, and what a recipient actually sees. Read
- Category Provenance vs AI detection A comparison against a signed record is a different job from guessing whether pixels look synthetic. Read
- Ceiling Threat model What a passing check can show, what it does not, and what is disclosed in every manifest. Read
- Live Can you tell which one changed? Pick the altered copy, then run the shipping verifier on both files. Read