VerifiablyBased Journal
What Makes a Photo Verifiable?
A practical walkthrough of how device-attested, C2PA-signed captures turn images into portable proofs.
Most integrity systems still depend on trust in platforms. We are building for proof portability: the evidence should travel with the image.
The Three Guarantees
- Integrity from the moment of capture, signed in the device's secure hardware
- Cryptographic binding between the image and its provenance claim
- Public verifiability without access to private infrastructure
Why This Matters
If authenticity depends on a closed system, an external reviewer still has to trust someone. A verifiable artifact should be auditable anywhere.
| Property | Legacy Upload Proof | C2PA-Signed Capture |
|---|---|---|
| Verify offline | No | Yes |
| Detect tampering | Often indirect | Direct |
| Portable evidence | Limited | Native |
Minimal Verification Flow
import { verifyProofBundle } from "@verifiablybased/sdk";
const result = await verifyProofBundle(bundle);
if (!result.valid) {
throw new Error("Proof verification failed");
}
console.log("Signer:", result.signer);
console.log("SignedAt:", result.signedAt);The verifier does not need to know who sent the file first. They only need the bundle and the public verification logic.