I've been using the jedi mp3 tag id3v2 to read mp3 files meta tags.
And been looking for such a thing on mp4 files. I know there is an option to do that using the FFVCL shareware library using the metatag field. The ffvcl is a library that read/write media files.
If you have a library that can do that except the one offered in the ffvcl -- with source code in delphi -- Please reply