well, that does not seem to be a very constructive answer. mind sharing some info/references on this specific one, or any others ? because I though it's a blackbox type of software
Here's a reference I googled for you https://www.toptal.com/algorithms/shazam-it-music-processing...
As for the reference you provided I know how shazam works, they pretty much made a blog post about it. This is not that. Not by a long shot.