Music metadata management
Neither Plex or Jellyfin respect the folder organisation of material so my original structure of separate folders for each composer in the "Music Classical" folder never worked. At least Nextcloud Music app has an albums and folders option, but it would be nice to descend into the tree as one does in the files app. That would be an alternative to being able to define separate libraries. The key element here though is that the app uses embedded metadata and local images rather than trying to be clever and extract everything on-line. This leaves gaps in the information such as the artist or composer summaries but I can live with that as long as I can essentially play a CD is if I'd loaded it. Something which is almost impossible with the classic material in Plex.
Just as Plex and Jellyfin are different ways of doing the same thing, Discogs and MusicBrainz have differences in their approach to the same problem. The advantage with Discogs is that it is working with real media and tends to follow exactly the titles used on the that, while MusicBrainz seems to want to standardise things that do not need to be. That we now have a means of cloning new disk metadata from one to the other is a help, and I used that to complete a rework of the 30 Years of Pop 20 CD set which has been handled nicely in Plex and Jellyfin after I tidied my local structure. Today this is saved as a directory with 20 separate directories, one for each CD, rather than appending the file titles with 'disk number-track number' which makes sense since none of the disks are numbered unlike smaller multi CD sets. 100 Hits Christmas also got the treatment even though Christmas is over. This is 4 CDs and a Karaoke DVD, with each CD numbered. Now that they have been processed once again through picard, the disk-track numbering has been added, and augmented with the Artist, before adding the actual title. I can now remove the CDx/DVD folder layer which will help in Nextcloud. The DVD folder does not get displayed anyway as it consists of mkv videos, but a conversion of the sound tracks to mp3 has given a usable set of track names, only marred by a mistake in the later track ordering and an incorrect track. My local copy is right, but it will be a week before MusicBrainz approves the correction.
So the trick moving forward is to run everything through picard to check the embedded metadata and any cover disk. A bonus here is that dolphin is using the embedded image as it's icon which is nice, and restructuring things gives bonuses there as well. Currently my top level structure on Nextcloud combines the 'Music Modern' and 'Music Classical' but renamed 'Classical', which contains the composer folder, 'Modern Artists' and 'Various Artists', but that is probably better as 'Modern Compilations'. I can then add 'Classical Compilations' for CDs that feature multiple composers, but often only one artist. It is that final set that neither Plex or Jellyfin do well with, and I still need to investigate and I have a pair of disks from the 'Classic Experience II' set in the player at the moment. MusicBrainz has returned a set of metadata to picard, but that lacks the composer tag. I can add manually locally, but better to update MusicBrainz and wait for that to filter through. I've a few similar sets I picked up from the charity shops around here so I can link everything to the real media. The booklets have all the missing composers as well as the performers ... it's just the time it takes to push it through MusicBrainz, but at least it will help others!
OK there is a reference to the composer for each track in MusicBrainz except that it is not in the main info section but in the secondary information. What I missed was that the latest metadata does have the composer in the artist field, while the raw data provides the performer in that field. Need to do even more digging to find out what is going on!
I am getting back up to speed with all three elements, picard, Discogs and MusicBrainz, and that is another area that needs a little time spent on useful crib sheets to save time in the future. I am sure I am making the same mistakes I made over a year ago last time I used them. The good thing is that all THAT history is in the MusicBrainz edit history.