Q: "Are they each from a single piece of paper?"
A: Yes -- by far the most frequently asked question, and the easiest one to answer (I wish they all were simple yes/no questions). But it is usually followed up with "...because some of them look like they're woven..." which is not actually a question, but an observation, and an implied invitation for me to elaborate on the masks' construction. So I elaborate. It's a technique that is both structural and ornamental. Parallel folds make pleats that open up to form the convexities of the face and intersect with each other around the face. Where they intersect, twist folds are formed on the back of the piece which help to keep the pleats closed. The pleats get pretty tightly packed together, and where they run parallel to each other, the space between them looks like an individual strip of paper from the front. Where twist folds occur on the back, it appears that the "strips" of paper are crossing under and over one another.
That's pretty ridiculously awesome, and an excellent illustration of art expressed within, and amplified by, a strict set of constraints. (It's also very cool of the artist to share their abortive efforts; the benefit of "negative knowledge" is often under-appreciated.)
I wonder if it'd be possible to adopt a handful of atomic / intrinsic / fundamental folding/creasing operations, and automatically build crease patterns for various 3D meshes?
(FWIW, I've spent a few spare cycles thinking about how to adopt mostly-raster animations such as xswarm to drive a "traditional" laser light show, where optimizing deflector moments is important; this strikes me as a similar task.)
This is begging for a start-to-finish time-lapse video.
Reminds me of http://www.amazon.com/Sculptural-Origami-Innovative-Gallery-Papercraft/dp/0486478408/ref=sr_1_12?ie=UTF8&qid=1327679718&sr=8-12 , which I got for Christmas. Pretty cool stuff.
If ever a book needed a few "See Inside!" pages available online..