Credentio
Google's open-source C++ library for verifying C2PA Content Credentials on a device, without sending files to a server.
Credentio is a piece of software Google released under the Apache licence in August 2026. Its job is narrow and useful: read the invisible, cryptographically signed record attached to an image, video or document and report whether that record checks out. Those records are called Content Credentials and follow the C2PA standard, and they say things like which camera or which model produced the file and what was done to it afterwards.
The important design choice is that Credentio runs locally. Nothing is uploaded, which matters when the whole point of the exercise is trust. Google says the same code already runs inside nearly 40 of its own products, and it supports C2PA versions 2.2 and 2.4. Bear in mind what it can and cannot tell you: a valid credential proves the file carries a genuine signature, not that the picture is honest, and a file with no credential at all proves nothing either way.