If I understand correctly, the only way to store meta data or notes attached to a file is via a comment or tags. I have a client who wants to store notes on files and be able to type free text such as:
Video of Joe and Sally at the beach in Venice from February 2015. I think Tommy took this with his Hitachi camera.
Or perhaps even better, a set of fields such as "Description," "Date," "Author" etc.
Perhaps this is a candidate for an app.
Any suggestions welcome.