This is based on old Echonest scanner. Echonest was bought out by spotify. Echonest had same issue as AcousticBrains, their first scanner sucked and mid way had to ask people to rescan using a new version.

Echonest used to provide source code, but after being bought by spotify, they stopped updating their code, disabled fingerprint server, etc: https://github.com/spotify/echoprint-codegen