Originally Posted by
CPRich
So I'm curious as to how Apple will know that a track I have is valid. It says it won't match <96kpbs files, >200MB files, DRM files not authorized to that device But if I copy an existing file and rename it "Texas Flood.mp3" and put "Stevie Ray Vaughn" as the artist and "Texas Flood" as the album, how is Apple going to know that's not what it is?
Doing actual matching via the track contents would seem to be compute/network intensive.
It's not that intensive; Shazam for iPhone and Android can match a song in a noisy bar with ten seconds of recording out of a collection of 20,000 songs in less than half a second on a normal desktop computer[1], and iTunes Match has a "radio quality" sample that Shazam's algorithm could do in a hundredth of a second. Additionally, they can fingerprint over the whole song (with a similar number of samples as Shazam's ten second fingerprint), allowing for a better match with less randomness.
1:
http://www.ee.columbia.edu/~dpwe/pap...g03-shazam.pdf