[Cryptography] Recognizing faces vs. recognizing a face

[John Levine]

This question seems vaguely cryptography related, I hope.

It seems to me there are two rather different applications called
facial recognition.

One is comparing an image of a person to a stored picture and deciding
whether it is the same person, yes or no.  That's used in various
countries' automated immigration kiosks, and I think Heathrow airport
uses it to check that the person who gets on the plane is the same
one whose passport they checked at security.

The other has stored pictures of people of interest, and a stream of
images of people typically from live video, and compares all the
people in the pictures to all the people in the images, looking for
matches.

The accuracy numbers I've seen all seem to combine the two.  Are there
separate analyses?  I would imagine that the single match would be a
lot more accurate than many to many.

-- 
Regards,
John Levine, johnl at taugh.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly