Genre not copied from ID3v2 to ID3v1 tag

When copying ID3 tag in mp3 from v2 to v1, or just changing tags and saving, Genre is not saved in ID3v1 at all, if more than 1 genre is used in ID3v2 tag (quite often now).

For example:
ID3v2 tag:

  • genre: Pop/Rock
  • year: 2020-01-01
  • track: 01/10

ID3v1 tag:

  • genre:
  • year: 2020
  • track: 1

Conclusion, year and track is copied/saved to ID3v1 tag, but genre is not saved at all, so it's missing, it's a problem in some programs, which support only v1 tags.

Solution would be to copy the first genre to ID3v1 tag, if possible, at least as option, I think it's still better to have 1 genre (of 2 or 3) than no genre.

MP3TAG v3.04a, Windows 10 2004 64-bit.

As far as I can see there is only 1 genre and that is called Pop/Rock.
If you want to define the first genre, then you probably have to split the genre so that GENRE becomes a multi-value field.

Hm.. some files have even 3 or 4 genres, it doesn't matter if it's 1 or multiple genres, the problem is, that ID3v1 tag does not support such genres and this field is completely empty.

How to split the genre?

Anyway, I can do it manually, but I prefer it would be automatic.

BTW Artist and Title fields are not completely copied from v2 to v1 tag either, because v1 tag field length is limited, but if no artist would be copied instead of 1 - of 2, it would not be good IMO.

See the action

Thanks, but it's just additional step, moreover, Genres use different dividers - and I don't need to split it, just save the first Genre to v1 tag.

BTW Even if Genre item exist in v1 tag, when I save the file in MP3TAG, Genre is removed from v1 tag, perhaps it could be considered as a bug.

No, genres do not use different dividers. There are defined default genres that also get recognized by V1 as they can be mapped to the V1 genre number and there are user-defined genres. And your exampe "Pop/Rock" is a user-defined genre for which there is no match in the pre-defined list for V1 tags.

In (some of) my mp3 files Genres use different dividers. I don't know if it's correct or not, it's a fact, and it's lost/not saved to v1 tag.

I don't doubt that you have user-defined genres that feature different non-alphabetic characters.
But please see this wikipedia article on the pre-defined genres which can be found in V1 tags:

If your genre (including the "separator") is not part of that list, it cannot be mapped.
If you have data in the V1 tag in GENRE and you save the tag again, then the GENRE from the V2 tag will be mapped to V1 - and if there is no match ...