No such luck with the iPhone X, though. Apple's investment in its tech - which saw the company work with a Hollywood studio to create realistic masks to test Face ID - has clearly paid off. It was impossible to break in with the model.

I imagine this is because the printed head isn’t anything but one-color under IR, it’s all the same temperature, right?

Seems like an interesting challenge to create a heated fake head.

The IR camera and the dot projector they use it with are in the near IR range (as in wavelengths near the visible part of the spectrum). It’s mostly only used to get depth data, and it’s near-IR so that you don’t get a bunch of visible dots projected onto your face every time you use it.

I guess you could see temperatures, but you’d have to point it at something almost hot enough to emit visible light. For normal face temperatures you’d need something sensitive to far IR.

If it’s just 3D without heat mapping, why don’t masks work?

I mean... A quick search would show you that masks can work. But I’ll bite.

It’s really precise 3D with a greyscale non-thermal IR image. Could be inaccurate masks? Missing details around the eyes and mouth and other important areas? Do masks have eyes with a discernable gaze direction? Do they have microexpressions or natural facial deformation? Do the eyes move?

There’s a buttload of stuff they could be measuring that is insanely hard to replicate with a mask. Besides, a thermal map would be pretty much useless even if the hardware was capable of thermal imaging. Skin temperature varies a lot (and not always uniformly) based on ambient conditions, physical exertion, being sick, sitting in direct sunlight, etc, etc.

Hmm I wonder if it is gaze detection. Seems like if you can detect gaze direction fast enough you could use the presence or absence of saccades to tell if it's a real live person or not. Doing that in a mask/bust would be fairly difficult.

It could also be looking at small changes like the periodic flushing that happens (see [0]). Though I'm not sure how well that would work on a moving phone but it could work I think just at a broader scale. FaceID is really fast though so not certain there's enough time to gather the data for that either.

[0] http://people.csail.mit.edu/mrub/vidmag/

It has been proven that Face ID can be fooled for a while now. http://www.bkav.com/d/top-news/-/view_content/content/103968...

Edit: changed 'circumvented' to 'fooled'

fwiw: with a $200 mask