Why UCFR?
- Simplified model: Three core structs — Claim, ExternalID, Method.
- Neutral core: No policy thresholds on‑chain; applications apply their own logic.
- Future‑proof: Methods are islands; new methods add new IDs without migrations.
- Open‑source first: Built on widely available, community‑verified methods; vendor‑neutral.
- Composable: Works with C2PA and W3C VCs; on‑chain metadata uses canonical JSON (RFC 8785).
Who is involved?
Logos shown for context; UCFR is a neutral public good and not affiliated with these organizations.
Claim
- fingerprint: bytes
- methodId: uint16
- externalId: uint16 (optional)
- externalSig / pubKey: bytes (optional)
- metadata / extURI: string (optional)
- owner, timestamp
Keyed by digest of (fingerprint, methodId, extId). Immutable once written.
ExternalID
- extId: uint16
- specURI: string
- sigSizeHint: uint32 (0 = variable)
- isSymmetric: bool
- active: bool
Signature/MAC schemes (e.g., RSA‑PSS, ECDSA, Ed25519, HMAC).
Method
- methodId: uint16
- name: string
- specURI: string
- fpSizeBytes: uint32
- active: bool
Hashing algorithms (e.g., SHA‑256, BLAKE3, PDQ).
Desktop Application
Real‑time folder monitoring, automatic hash generation and signing, metadata with AI declarations, and a simple UI that hides blockchain complexity.
GeneralizedClaimRegistry
On‑chain registry for cryptographic claims with multiple hashing methods, optional external signatures/MACs, immutable storage, and batch submission.
Blockchain Infrastructure
Built on the Stability network with ZKT support for streamlined transactions and public, immutable verification.
Workflow
- Configure defaults and select folders to monitor.
- App detects new files and computes fingerprints (SHA‑256 by default).
- Checks the registry for existing claims.
- New files are signed and submitted on‑chain.
- Existing claims are compared; mismatches prompt review.
- Visual status keeps track of verification and submission state.
What makes UCFR different?
- Hijack‑resistant: Perceptual hashes can't claim ownership; only exact digests can.
- Simple and stable: Compact on‑chain core; simple to integrate.
- Interoperable: Designed to snap into C2PA, VC 2.0, and common fingerprint libraries.
Method examples by media type
Image
- PDQ, pHash, aHash, dHash, OpenCV BlockMeanHash, ColorMomentHash
Audio
- Chromaprint/AcoustID, Shazam‑style, audfprint
Video
- TMK+PDQF, vPDQ, OpenCV frame hashes
File/Generic
- SHA‑256, SHA3‑256, BLAKE3
Text
- MinHash, SimHash, Winnowing
Device/Camera
- PRNU, Noiseprint
These are open‑source friendly examples; UCFR remains extensible without migrations (island model).
Security & Privacy
- Local key storage: Private keys are generated, encrypted, and stored locally. They never leave your device.
- Transparent AI declarations: Per‑file metadata can declare AI involvement for downstream transparency.
- Decentralized verification: Anyone can verify claims on‑chain without trusting a central authority.
- Optional crash reporting: Privacy‑preserving diagnostics with no keys or sensitive contents.
Immutable by design
Claims are append‑only and cannot be altered or deleted, providing durable provenance records.