Are there any open-source reference implementations?

[nealmcb]

Multiple independent implementations are often required to promote interoperable standards.
Thank you!

[lrosenthol]

Adobe and the Content Authenticity Initiative (CAI) recently released an open source implementation at https://opensource.contentauthenticity.org/

NOTE: this is NOT a reference implementation, but is certainly a valid implementation.

We look forward to other implementations - either full or partial - in the future.

[gregorym]

Now that we're in 2024, any other references we can look at?

[lrosenthol]

@gregorym For a read-only one, ExifTool (https://exiftool.org/) is an option. You can also use pretty much as ISOBMFF library - such as ones in Python, JavaScript, C++, etc.

However, AFAIK, the CAI library is the only writing one available as open source.

[cyraxx]

We have recently open-sourced c2pa-ts which is an independent implementation supporting reading and writing.

Also definitely not a reference implementation, but an implementation.