Paramount Pictures Ray Winstone's acting was digitally captured and modified by computer for "Beowulf," which will be judged by the Motion Picture Academy as an animated feature.

LOS ANGELES — The tagline for Disney's upcoming "Enchanted" could well be the motto for the latest push in animation: "The real world and the animated world collide."

Not in the slapstick tradition of 1988's pioneering "Who Framed Roger Rabbit?," but in the sense of transforming actors into animated characters and vice versa.

The technique is seen in Charles Schwab TV ads and Richard Linklater's bomb from last year, "A Scanner Darkly." Peter Jackson and Steven Spielberg are collaborating to make three comics-based movies blending performances with computer graphics.

The lines have been rendered so blurry that even close observers of the industry are asking what seems an easy question: What is animation?

The director of "Roger Rabbit" has created a film that challenges whatever your answer may be. Robert Zemeckis' "Beowulf" marries filmed actor performances, animation and special effects to create a unique, semi-but-not-quite-realistic look that many identify more with video games than movies.

It arrived in IMAX and regular theaters nationwide on Friday with weekend box office earnings of $27.5 million, 3-D glasses and the stamp of "animation" from the Academy of Motion Picture Arts and Sciences. It qualifies under academy rules — revised several months ago to require "frame by frame" work — to compete for an Animated Feature Oscar against the likes of "Ratatouille" and the black-and-white 2-D Iranian film "Persepolis."

But because of its hybrid nature, few in the animation world expect it'll actually be one of the three nominees. That possibility distresses traditional animators.

"It's a little bit odd when they're being put in the category competing in the same way for awards," said Kevin Koch, a longtime animator of DreamWorks films such as "Over the Hedge" and "Shrek 2." "Some of us are kind of scratching our heads a bit."

The intricate detail of "Beowulf" is what sets it apart, but it was created with a motion-capture process similar to those used in recognizably cartoonish movies. Child actors overacted before a green screen as the basis of last year's animated Oscar nominee "Monster House," and dancer Savion Glover supplied the penguins' smooth moves for winner "Happy Feet."

"If you ask the average animator what they think, they'll tell you they don't think motion capture is animation," said Jimmy Hayward, an animator on "Toy Story" and other Pixar films.

Yet there have never been bright lines. The technique of rotoscoping — capturing human movement in images and then tracing those into the cartoon world — was invented by Max Fleisher in the 1910s and even incorporated into key early Disney cartoon features such as 1937's "Snow White and the Seven Dwarfs."

So what's the problem with that? And who are today's animators to talk, anyway? They long ago traded in pen and paper for customized computer rendering programs.

"The essence of caricaturing life is an art form, and it's its own art form," said Hayward, who is now directing an animated Dr. Seuss feature, "Horton Hears a Who," due in March. "Motion capture is outside of all the craft that goes into the other parts of it."

It should be said: The creators of "Beowulf" don't call it animation, nor do they intend to replicate real life.

Jerome Chen, visual effects supervisor for "Beowulf," oversaw some 500 animators and worked on the project for three years. He argues that it should be included in the animation category.

"An artist still has to tune this software program. We use 3-D animation tools, but an animator still has to slave over key frames," Chen said. "The computer program is really just a sophisticated brush in that sense."

Chen said animators regularly tweaked the facial expressions or movements of actors depicted in the film.

Just don't try telling Ray Winstone, who plays the title character, that somebody changed his acting. "To me, I can't see where performances were changed," he said. "We all played our parts."