The BMFF defines a meta data track as a track which can appear in the media file in addition to video & audio tracks. Such a track can be in the form of xml (metx), text (mett) or binary (urim).
Is there a library which is capable of taking a mp4 file as an input and appending a metadata track to it? Is there a sample mp4 to inspect and learn the exact structure of such a file?
Specifically, I'm interested in adding such a track to a fragmented mp4 file.