From an article on the animation:
Emily - the woman in the above animation - was produced using a new modelling technology that enables the most minute details of a facial expression to be captured and recreated.
She is considered to be one of the first animations to have overleapt a long-standing barrier known as 'uncanny valley' - which refers to the perception that animation looks less realistic as it approaches human likeness.
Researchers at a Californian company which makes computer-generated imagery for Hollywood films started with a video of an employee talking. They then broke down down the facial movements down into dozens of smaller movements, each of which was given a 'control system'.
The team at Image Metrics - which produced the animation for the Grand Theft Auto computer game - then recreated the gestures, movement by movement, in a model. The aim was to overcome the traditional difficulties of animating a human face, for instance that the skin looks too shiny, or that the movements are too symmetrical.
"Ninety per cent of the work is convincing people that the eyes are real," Mike Starkenburg, chief operating officer of Image Metrics, said.
"The subtlety of the timing of eye movements is a big one. People also have a natural asymmetry - for instance, in the muscles in the side of their face. Those types of imperfections aren't that significant but they are what makes people look real."