Actors dress in Lycra suits with reflective marks that allow the cameras to track their movements and feed the data to visual effects specialists.
They can digitally overlay images using the actors' exact movements and expressions making the results more realistic and more complex than other digital effects.
Phil Elderfield, entertainment product manager at Vicon, which makes motion-capture systems, said: "We are teetering on the edge of recognition for some performances motion capture has delivered. This is a remarkable piece of work and Andy's performance is deserving of consideration."
But Hollywood star Jeff Bridges has sounded a note of caution. "Actors will kind of be a thing of the past," he told the LA Times.
"We'll be turned into combinations. A director will be able to say: 'I want 60 per cent Clooney; give me 10 per cent Bridges and throw some Charles Bronson in there'."
The cast of the Apes movie are in Los Angeles to promote the DVD release of the film, which proved a smash hit in cinemas, taking US$707.4 million ($897.3m) at box offices around the world.
According to industry insiders it is likely Serkis' case for the nomination will be pushed while he is there.
Serkis has become the godfather of motion capture, using the technology to create iconic characters including Gollum from The Lord of the Rings series and King Kong.
Yet Apes co-star Gary Oldman has cast doubt over whether his performance was "the sort of thing" the Academy will accept because of the heavy use of computer-generated imagery.
Julie Parmenter, managing director of UK film and television post-production house Molinare, said: "In this case, the animal he's portraying comes from his expertise and understanding of the role and that is truly acting.
"It is a powerful role in the film, a costume may have been superimposed on him but it's still him acting."
A similar row broke out in 2010 when fans of Avatar made a case for its stars including Sigourney Weaver to be recognised by the Academy despite being cloaked under digital imagery.
Parmenter added: "It is a fine line. Too far and you're just going into the realms of animation.
"This film has a much stronger case than Avatar. That looked really computer generated. With this it looks like there is someone still there underneath."
Four years on and times may be changing over the use of motion capture, which depends on the actor beneath the pixels.
Martin Brown, assistant general secretary of actors' union Equity, said: "It simply hasn't been a matter for debate in Equity.
"No one is asking if Andy Serkis is acting or not.
"No concerns have been raised to us. It's new work and actors are moving with it."
The 50-year-old Serkis describes himself as "evangelical" about the technology and has even set up his own motion-capture company, The Imaginarium Studios. He has long believed motion capture had not been given its due.
He said there was no difference between his non-digital performance as Ian Drury in Sex & Drugs & Rock & Roll and Caesar.
"How it's cloaked and manifested on screen, that's a different thing, but people often don't get that it is all acting."
- Independent
