Checking an image against perceptual hashes is a little more than a string comparison, but that's moot. Also, "scanning" does not require anything be leaked for someone to call it that, which is again, almost definitely what the person you replied to meant when they used the word. Your insistence here that the word doesn't fit that situation is peculiar.
Reporting filesystem stats is simply a bad analogy, it's not like checking image contents against perceptual hashes.
