Google released Credentio on August 13, 2026, an open-source C++ library for working with C2PA (Coalition for Content Provenance and Authenticity) Content Credentials, starting with specification versions 2.2 and 2.4 1. Google says this is the same code that has powered nearly 40 different C2PA-enabled Google products to scale to tens of billions of generated assets, including images, videos, audio files, and documents 1. The repository is at mediaprovenance.googlesource.com 1.
The design point is local-first validation. The API is built to run completely locally inside developer applications, removing the need to send media files to cloud servers for validation 1. Google states that media files never need to be transmitted back to Google or to external validation endpoints, citing zero bandwidth overhead, immediate validation verdicts, and media contents staying within the local environment 1. Custom or official trust lists — including the C2PA Trust List and C2PA TSA Trust List — can be passed through the API, and the library performs deep inspection of manifests, assertions, digital signatures, and claim structures 1. For now it focuses on validation; generating Content Credentials and embedding them into media files is planned as a future expansion 1. The same week, Google also announced a setting that makes Gemini’s visible watermark optional while keeping invisible SynthID and C2PA metadata in place.
Sources
- Introducing Credentio: Open Source C++ Library for C2PA Content Credentials from Google - Google Developers Blog (August 13, 2026)