[FFmpeg-devel] Support of QuickTime metadata atoms

[Kevin Wheatley]

Hi,

I'm considering adding support for writing the QuickTime metadata atom
structure to support arbitrary key value pairs, similar to those
included by ARRI cameras see:

https://developer.apple.com/library/prerelease/mac/documentation/QuickTime/QTFF/qtff.pdf

p128

To start I was going to try add reading of the metadata, as such I was
wondering about FFmpeg's current metadata handling and how to add the
metadata found in these atoms to the internal structures.

Nominally these metadata atoms can appear in multiple places within
the QuickTime file.

In particular I wondered if there is any need for name spacing the
keys similar to the way the QuickTime specifications use the 'mdta'
handler field both as a way to distinguish from the current 'well
known named' metadata as well as to potentially support multiple sets
of metadata from different parts of the atom tree hierarchy (I haven't
worked out if there is a 1:1 mapping with the way ffmpeg currently
stores metadata vs potential positions in the atom tree)

Has anybody considered this previously and could point me in the right
direction?

Thanks

Kevin