Reminds me a lot of MusicBrainz Tagger, I remember being fascinated by it in 2001 ( https://web.archive.org/web/20010107213100/http://musicbrain... ) because it was able to "identify" the song in the mp3/wma/ogg file and download the correct tags.

I remember studying this paper as a student, was completely amazing, a bit mysterious and not so difficult to understand at the same time.

And most of all: no ML involved! All hail the heuristics!