CANNES, France (AP) - After nine hits and four Academy Awards for films including "WALL-E" and "Ratatouille," the Pixar Animation gang finally feels it has made it to the grown-ups' table with "Up," the first animated movie to open the Cannes Film Festival.

The Oscars compartmentalize animated films into their own category. Audiences often do the same, lumping animation in as a genre meant mainly for kids. But Pixar's creative minds feel the choice of "Up" as the Cannes curtain raiser signals that animation can stand alongside the best that live-action films might offer.

"It is one of the greatest kinds of rewards, it's one of the greatest things that's happened to us in our career," said Pixar's John Lasseter, who pioneered feature-length computer animation with the two "Toy Story" movies.

"To see animation respected at the world's premier film festival. To be given opening night ... you pinch yourself. You just can't believe it," said Lasseter, who also oversees animation at Walt Disney, Pixar's parent company.

The English-language version of "Up" features Edward Asner providing the voice of Carl Fredricksen, a brokenhearted widower who renews his spirit of adventure after floating his house off to South America under thousands of helium balloons. The film is released in U.S. theaters on May 29.

"Up" has moments of deep pathos, including a couple of sequences that brought tears to viewers' eyes in preview screenings as Carl's life with his beloved wife is chronicled in montages and old photos.

"There's a perception that animated films are for kids. A lot of people have that, which I think is very unfortunate. The films are made by adults who have very adult concerns," said Ed Catmull, president of Disney and Pixar's animation studios. "What happens now at Cannes is they're recognizing it as a film. Not as a category, but as a really great film."

While the movies can soar off on whatever flights of fancy the animators imagine, Pixar aims to ground the stories in human emotion, whether they're about talking fish ("Finding Nemo"), working-class superheroes ("The Incredibles") or chatty autos ("Cars").

"Up" director Pete Docter said animation was a tool, not the star.

"It's not a genre, it's a medium. Animation can do anything. If we decided to, we could do horror films or drama, suspense, anything," said Docter, who also made Pixar's "Monsters, Inc."

"We think about characters much in the same way live-action filmmakers think about the characters. Motivation and underlying goals, and needs and wants," he said.

"Up" producer Jonas Rivera said Pixar thinks of its productions not as animated films, but as films that "happen to be animated."

"Sometimes, you feel like animation sits at the little kids' table," Rivera said. "We just want to make films that people enjoy, so to be honored with opening night at the festival, it feels a little bit like, OK, maybe somebody else sees that, too. ... This is the big kids' table."

Copyright 2009 The Associated Press.