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FactLockCam

Exact-file integrity

How to prove a photo was not altered

Start with a capture record that already exists. Then ask whether a later file still matches that record. Change the file. Break the match.

  • Earlier record first
  • Byte-for-byte comparison
  • Not an AI detector

The sequence that can be checked

  1. Capture the photo or video inside FactLockCam before the scene changes.
  2. The app fingerprints the exact bytes, signs the capture record, and can publish the record hash to Polygon.
  3. Send a .flcproof package. A recipient opens it locally at /open.
  4. The verifier compares the inspected file with the earlier fingerprint, then checks the signature and, when present, the public record.

What this is not

This is not an AI detector. It does not score whether pixels “look synthetic.” It compares a specific file with an earlier signed record. Verifies the exact file and signed record—not the physical truth of the scene.

Try the live pair on Can you tell which one changed? The original matches. The demonstration altered copy returns media_hash_mismatch.

Next step

Create the earlier record.

A comparison needs a reference. FactLockCam makes the reference the moment you capture.

Anchor your first capture Run the proof challenge