I don't use rating myself, but from reading the MM thread I linked I think I have a basic understanding of the issues. I think the mapping in PR 10866 addresses most issues. In the case of MM they have a design goal of compatibility with windows / WMP since they are a windows platform program. That seems to have caused the unintuitive mapping.
I note in the ParseTag function for ID3v2, there is the possibility of "
[email protected]xbmc.org". I guess this was an attempt to allow for Kodi to write userrating back to the POPM tag?
One thing I am wondering, though, IIUC for Vorbis RATING tag, 0-9 will be set to userrating 0. Seems like RATING 0 only should be 0 since I think RATING 0 and NULL both imply "unrated" as does userrating 0, or am I wrong about this?. I didn't follow all the "userrating" design battles, but ISTM that "unrated" should be unique, like -1. That way a Vorbis RATING of 1-9 could be set as 0 and still have meaning, though to be consistent with POPM I guess it should be 1 (0.5 stars).
Of course this assumes anyone uses Vorbis RATING, unless we get a complaint answer is probably "no".
scott s.
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