Andy Serkis gets "frustrated" performance capture is misunderstood.

The 47-year-old actor - who has played used the technique in 'Lord Of The Rings' to portray Gollum and chimpanzee Ceaser in new movie 'Rise of the Planet Of The Apes' - is irritated people do not understand how the system works, believing it to be simple, whereas he actually has to act as normal but in a specialised suit.

He said: "I'm a bit evangelical, I know. But performance capture is still misunderstood. 10 years down the line, people say, 'Oh so you did the voice of Gollum?' Or people go, 'You did the movements for Kong?' It's frustrating, because I play Gollum and I play Kong. It's acting."

The British star believes a good comparison is to his role as Ian Dury in 'Sex and Drugs and Rock 'n' Roll' - although no motion capture technology he is used, it is still him acting.

He told the Daily Telegraph: "There's no distinction between how I play Ian Dury in that film, and how I play Caesar in The 'Rise of the Planet of the Apes'.

"How it's cloaked and manifested on screen, that's a different thing, but people often don't get that it is all acting."