I have a custom field "Producer" in most of my music, it seems Kodi can only scan and identify that field within the .wma and m4a file format but not the mp3 format, i just recently realized this yesterday, before i couldn't understand why when i checked the "producer" node in the library only some would show up. Is there a way to detect the custom field in the mp3s.
At the moment Kodi (v17) does not process arbitrary custom tags, although it is something I am looking into. But if it did process custom tags, then there would still be no way for it to know which ones happend to be artist roles.
In mp3 files the ID3 v2.4 tagging standard specifies that producer goes into the TIPL tag, and Kodi does process that. Try retagging your mp3 files, putting the producer in the TIPL tag e.g. TIPL = "Producer", "Tom Smith", you should be able to get the tagging software to copy your custom tag value.
First person I have heard using the producer node, great
yes, i m the one that requested for custom fields to be recognized by kodi, specifically producer and dj.
i see that "remixed by" works in most formats; mp3 wma m4a. just not "producer" im goin to look up tipl, im not sure what that is.
The remixer tag in ID3 is TPE4, and if you have tagged using it then Krypton processes it. For mp3 files roles like Arranger, Engineer, Producer, DJMixer or Mixer are all covered by the TIPL tag the "involved people list", populated as a list of values with role in the odd entries and name (or list of names comma delimited) in the even entries.
Kodi v17 will process whatever is in TIPL or TMCL (Musician Credits List) tags as pairs of roles and artist names,so you could really make up whatever roles you like. Some roles like Arranger, Engineer, Producer, DJMixer and Mixer have standard tags in other tag formats, but PERFORMER in Vorbis is a similar way to add custom artist role values.
Bottom line I think that with a small tag change you should be able to get what you want from Kodi v17.