By Ian Youngs BBC News Online correspondent in Cannes

Jolie, Black and Smith said the film was a positive experience

The duo were in Cannes with fellow star Jack Black to speak about their latest film, Dreamworks animation Shark Tale.

Making the upcoming film was "liberating", Smith said, as it helped him rediscover a freedom in his acting.

Jolie said the speed at which animation was advancing was exciting, while Black said voice work was simply "easier".

Also starring the voices of Robert de Niro and Renee Zellweger, Shark Tale has been made by the same studio that produced Shrek.

Smith said the booth for recording characters' voices was a space where "you're allowed to do anything".

"It's actually helped me in my acting performances in 'real films'," he said.

The film's three leads took to the water to promote the film at Cannes

"The animated performances have helped me create and find a freedom I used to have.

"I'm finding it a lot easier to find that space in live action now."

He added that there was more opportunity to "create a memorable character" in animated films.

Jolie - who won an Oscar for Girl, Interrupted - revealed she had watched Shrek 60 times with her son.

She is attracted to making animations because the quality is getting better, she said, but added: "Mind you, I still like Dumbo.

"They're just great to watch, they're great stories and they're obviously advancing, so to be part of anything that's changing and advancing is exciting," she said.

Jolie said the quality of animations was improving

Meanwhile, Black, who starred in School of Rock, said animations were easier and gave him more time to get things right.

"It's not really the money - it doesn't pay as good - but it's also not as much work," he said.

"You go in and do a little talking and a little singing and screaming, and then you're done.

"It's easier and you have the chance of being part of something special."

Shark Tale, which is released in the US in October, used the Cannes limelight to attract attention but is not part of the festival's official line-up.