Curved dowel shaping machine - GIF

[desbromilow]

Surely there is magic involved here somehow?

I would suspect it is a fairly narrow cutter set with an aggressive leading chamfer and is essentially shaping the wood in an zone of around 10-20mm in length, and would be based on the relative hardness/cut resistance of the wood at the particular point in the timber.
I would expect the cutter set would somewhat resemble a rotating box tool.

Des