Motion capture technology to end 'stiff and unrealistic' on-screen animals

Four-legged creatures will be realistically portrayed with reliable results

Actors are warned about working with animals but scientists have now found a way of working with cats, dogs and horses without the risk of unreliable results.

Researchers are fine-tuning the technology of motion capture for the film industry so that it can realistically portray the movements of four-legged creatures without being the fear of being upstaged by unrealistic behaviour.

Although motion capture is used extensively to portray human movements in films and computer games, it is only recently being applied to the movement of animals, said Karl Abson, a motion-capture specialist at Bradford University.

Films such as War Horse or Life of Pi use computer-generated animation to portray difficult scenes involving animal characters but this is expensive and often produces “stiff and unrealistic” animals movements, Mr Abson said.

Motion capture, however, is a way of building up a computer-generated image but based on the real movement or actors or animals that are filmed simultaneously in infra-red light by several cameras positioned around the characters.

Light reflected off a set of markers attached to an animal’s coat or fur is used to generate a computerised image, with specialist software filling in the details or changing the overall look of the animal - a domestic cat for instance can be made to look like a tiger.

“We can’t move a big cat because it will kill you, but maybe if we could motion capture a tame cat we can see differences that could alter the movement in a film’s post-production, and it’s surprising how well it worked,” Mr Abson said.

“Motion capture on people has been done to death, animals not so much. The problem is that we’ve come really far in our ability to create skin textures and surfaces, such as the metal effect of Iron Man’s suit,” he said.

“This can fool audiences but when it comes to motion we are still in the dark ages. When you come to animate something with motion, you always notice the slightest problem. The more you create something real the harder it is,” he told the Science Festival in Bradford.

Mr Abson and his colleagues at Bradford are working with post-production film companies in London, Hollywood and Moscow. The researchers are skilled in the movements of horses, and motion capture has been used to simulate jousting knights and racing chariots.

“We need a way of doing things that is not biased towards people. That is what we use motion capture for - we watch the data, we measure the data to see how animals actually move,” Mr Abson said.

“We have programmed the software to understand the quadruped and capture actual horse movement. For a film it is much more cost-effective, it’s much more doable,” he said.