Track name atom ('tnam')
An atom that provides a name for a track.
Overview
A movie atom’s user data atom may contain a track name atom ('tnam').
A track can have multiple 'tnam' atoms with different language codes. Normally it is sufficient for each track to have a single 'tnam' atom in the same language as the track content. Alternate tracks might also have 'tnam' atoms; their presence implies only that the name is a good user-readable label for the track.