What sort of test could distinguish between:
A file named "Freebird.mp3" that that is in fact the actual track
A file named "Free-bird.mp3" that is an mp3 of white noise
A file named "freeburd.mp3" which is a song made available under an open source license by its creator....
short of downloading and listening to each one, that is....
“What sort of test could distinguish between:”
Proven technology is certainly out there to do that. Honest. Has been out there for a decade. The RIAA lawsuits make it more cost-effective to use those tools than to ignore the problem.