Steven Spielberg used actors Jamie Bell, Daniel Craig, Andy Serkis, Simon Pegg and Nick Frost to capture their movements and then turn them into digital animation characters.
The animation is the work of the company Weta Digital, responsible for the visual effects of the trilogy of "The Lord of the Rings" and "Avatar".
Having seen the trailer, although I was already very wrong with "Avatar", this film does not attract my attention so you will not see me at the cinema queuing to see it.