I did some reading on aac & m4a tagging standards (a.o. on AtomicParsley), and differences with id3v2 (I am not really concerned with legacy id3v1), I have read of course the MP3Tag help pages on tags, and have some questions regarding this.
What I understood (in layman’s words):
- mp3 files recommended tag format is id3v2 (metadata container), which is widely recognized/used; key points are a max 256MB of text in each tag
- aac files (raw, i.e. not embedded in mp4 container) also support id3v2
- m3a files (with embedded aac) have no standardized tagging system. iTunes/apple use their own system (called mp4?), with a max of 255 bytes per tag (except lyrics)
Now the questions …
- I read that m3a also can have id3v2 tags attached, and that iTunes also reads and supports this (although I read elsewhere that it is not supported). So is this possible? Do you need to use either/or, or can you have both at the same time?
- If id3v2 for m4a is possible, would you recommend to convert all these mp4 tags to id3v2 (and how to do this?)
- For my files that are listed in the MP3Tag navigation window as having mp4(mp4) tag, I assume that they use the apple/itunes tagging system (so with the max 255 bytes per tag?) So what happens if with MP3Tag I add an extended tag, which is not supported by mp4/apple/itunes (e.g. ORIGALBUM or ORIGARTIST), or if I put more text then 255 characters?