Has the uncanny valley been breached for digital humans? Perhaps not quite, but it's definitely going in that direction. The researchers at University of Southern California's Institute for Creative Technologies (USC-ICT) have come up with some very realistic CG skin that deforms on a microstructure level the way real human skin does when being subjected to squash and stretch.
This is possible through a new 10-micron scanning technique, which captures the microstructures in skin, such as skin pore texture and extremely fine lines. These details aren't normally recorded by modern scanning techniques which work on a meso level (the level between macro and micro), and don't capture microdynamics structures below one tenth of a millimeter. They're therefore left out of CG renders.
Skin is subject to squash and stretch, and becomes smoother when stretched and rougher when compressed. This affects facial reflectance, and it has a large impact on how we perceive facial expressions.
The researchers used the high-resolution scanning data from pulling and prodding skin to quantify how stretching smooths the skin and compression makes it rougher. The resulting surface normal distributions were tabulated and applied to a microstructure displacement map of neutral skin. Microstructure deformations and changes in surface normal distribution were then simulated by blurring the map in the direction of stretching and sharpening it in the direction of squashing, giving the appearance of realistic dynamic skin.
The Graphics Lab at USC-ICT are at the cutting edge of technology in the field of digital humans. Their earlier work includes attempts at creating a photoreal digital actor with Digital Emily, followed a few years later by a real-time photoreal digital actor with Digital Ira. More information about this and their projects can be found here.