I have a new biometric passport (what I mean by that is that it bears the chip sign on the cover), I haven't done any fingerprint or eye scans to get it though. How do the automated gates use the passport to check identity? Do I have register somewhere first in order to use them?

[This UK](http://www.nidirect.gov.uk/index/information-and-services/travel-transport-and-roads/public-transport/air-travel/using-epassport-gates-at-airport-border-control.htm) website suggests that they take all the information needed from the photograph. Is it really the case? And does it work in the same way in other countries?