eIDAS and C2PA

Why a photo alone proves very little

A photo can be edited, taken from somewhere else, or claimed to be from another day. When two parties disagree about the state of an item at a handover or a return, "I have a photo" is rarely enough.

tryVidimus seals the photo at the moment it is taken, with two independent recognized standards: C2PA, which records where the file comes from and keeps any change visible, and an eIDAS-qualified timestamp, which fixes the date. Anyone can check the result without trusting us.

C2PA: where the file comes from

C2PA is an open standard from the Coalition for Content Provenance and Authenticity, behind the "Content Credentials" used by camera makers, software publishers and media. A C2PA manifest travels inside the image file and is signed: it says which tool produced the file and keeps any later change detectable.

tryVidimus Proof Capture is a C2PA conformant Generator Product: the C2PA conformance program issued its Notice of Conformant Status on 19 October 2026, at assurance level 1, for JPEG photos. Each photo is kept twice: the original, untouched, and a signed copy that carries the C2PA manifest. The signing key is held in a managed key service and never leaves it.

eIDAS: a date you can rely on

eIDAS (Regulation (EU) No 910/2014) is the European framework for electronic trust services. It defines the qualified electronic time stamp: a time stamp issued by a qualified trust service provider, which has two effects in legal proceedings.

First, no time stamp may be refused as evidence only because it is electronic (article 41, paragraph 1). Second, a qualified time stamp enjoys the presumption that the date and time it shows are accurate and that the data it is bound to has not changed since (article 41, paragraph 2). The presumption can be challenged; it moves the burden of proof to the party who disputes it.

In production, each tryVidimus proof carries its own time stamp issued by Certigna, a French qualified trust service provider. In test mode the time stamp is simulated, has no legal value, and the verification page says so.

RFC 3161: the technical protocol

RFC 3161 is the Internet standard behind time stamps. We send the authority a fingerprint (SHA-256) of the proof, and it returns a signed token that binds that fingerprint to a certified date. The token is public: anyone can check it with common tools such as OpenSSL, without an account and without us.

What a sealed proof proves, and what it does not

A sealed proof shows, in a way anyone can verify:

• that these files existed at the latest at the certified date;
• that they have not been changed since (any change breaks the fingerprints and the signature);
• that they were captured through the tryVidimus capture flow, with the C2PA manifest of the signed copy.

Limits

A sealed proof does not say that a scene is truthful, who exactly the person was beyond the capture link they received, or what condition an item was really in: it shows what each party captured, and weighing it belongs to the parties and, if needed, to the judge.

The "captured at" time of each file is the moment our service observed it: it is not qualified. Only the time certified by the time stamp authority is. It is also not an electronic signature of the parties.

Check a proof yourself

Every proof has a public verification page that shows its status and its time stamp. The verifier is open source and published as a package, and the time stamp can be checked with OpenSSL. Questions: help@tryvidimus.com.