SOLVED: Where are album artist thumbnails saved?

[yamanobe]

Thanks for looking into this.

I guess my question did not come across well.
What name should jellyfin give the file name and where should I save it to in order to add the artist image or album artist image to the library?

I know this was not my question, but...
Thanks for telling me how to output the musicbrainz picard image file.
This works great as a way to output a large amount of embedded cover art.