BIG LEAP OF FAITH FOR `STUART LITTLE'; WHEN PROJECT STARTED, THIS TECHNOLOGY WASN'T INVENTED.

Byline: David Bloom Staff Writer

Imagine starting a project that will cost tens of millions of dollars to complete and that depends on technology that hasn't even been created yet. And if you fail, the result will be painfully obvious to millions of people.

A few years back, that's pretty much what Columbia Pictures and producer Douglas Wick did when they began serious production work on ``Stuart Little,'' a mostly live-action movie that opens Friday, featuring a computer-generated, remarkably believable image of a talking mouse as its lead character.

``When we started on Stuart, we were moving into an unknown technology,'' director Rob Minkoff said. ``We didn't know if we could do it.''

That sort of techno-artistic high-wire act is almost required these days if you want to do something memorable, said John Dykstra, the film's senior visual-effects supervisor, and now an independent effects consultant who has won both Oscars and Emmys (``Star Wars,'' ``Battlestar Galactica'') for his wizardry.

``It's a relatively accurate statement that if you go into a film that's meant to give you something you haven't seen before without using unknown technology, you'll be obsolete before the film comes out,'' Dykstra said.

The challenge appealed to Sony Imageworks, the corporate sibling of Columbia Pictures that created all the film's special effects, even to the point of little details such as how to finance a few dozen more of the 651 visual-effects shots.

``It was one of the most extensive projects anyone has ever done, not in terms of shot volume, but in terms of its intricacies,'' said Imageworks spokesman Don Levy. ``Its goal was to create a digital star of a live-action film and integrate it into the film in a realistic way.''

Of course, corporate parent Sony saw it all as one big, happy synergy, and invested a ``huge amount'' of money on research and development by its special-effects house to help create a special movie by one of its studios, Wick said. And despite the risks, Imageworks went way beyond the call of duty to help make the project work.

``It was a huge opportunity for them to really strut their stuff and do something that's never been done before,'' Wick said. ``It's their calling card, too.''

And it is quite a calling card. Imageworks has been showing off bits and pieces of the work for months now to people, at insider events such as the Visual Effects Society's first festival this summer and the SIGGRAPH conference on computer graphics.

``I have a hunch that `Stuart' is going to be real successful,'' said Chris Wedge, director of last year's Oscar-winning animated short, ``Bunny.'' ``From what I've seen, they've done it with a lot of sweetness. I'm glad someone is doing it.''

Consider ``Stuart'' as the next step in a series of increasingly convincing computer-generated characters in movies.

It started, of course, with the dinosaurs of ``Jurassic Park'' and its sequel, but kicked into high gear this year with several notable computer- created characters.

First, there was the bandaged bad guy in ``The Mummy,'' then the annoying but well-crafted Jar Jar Binks in ``Star Wars: Episode 1 - The Phantom Menace,'' and the toy collector and dachsund in the all-animated ``Toy Story 2.''

Each of these movies used recent computer-animation improvements that do a much better job of rendering clothing and fur in more lifelike ways. And to a large extent, they have succeeded.

But as Dykstra, Levy and others pointed out, those characters were largely caricatures or pure fantasy, so audiences had little from their own experience with which to compare them. They are also all supporting characters, so less depends on them for the film's success. That's not the case here.

``For my point of view, as a step (in the development of animation), we certainly stand on the shoulders of our precedents, but there was a huge movement made here,'' Dykstra said.

'Stuart' is the first major film to feature a wholly computer-generated character in the leading role, and to base him on something most audience members have seen before, a mouse.

Making something that looks like a believable mouse on screen is a challenge, ``Bunny'' creator Wedge said, but one that can be done if you just keep looking hard at nature's models.

``It's a trick, but an easy trick,'' Wedge said. ``You just compare what you're doing to a real mouse and keep saying, `What's wrong with this picture?' You keep comparing all day.''

Well, yes. It's sort of like looking at a block of stone, and removing all the things that don't look like a human. Easy for Rodin, maybe, and for Oscar winners. But it still takes some long slog-work, especially if you're creating your high-tech hammer and chisel as you go.

Stuart's look is the product of close collaboration between animation supervisor Henry F. Anderson III and director Minkoff, best-known as co- director of Disney's animated mega-hit ``The Lion King,'' and who worked with Anderson as though he were a lead animator in a Disney film.

Stuart's visualization started with E.B. White's book and its wonderful line drawings by Garth Williams, though their ``very 2-D'' look reduced their usefulness in a 3-D character's creation, Minkoff said.

``It had to be somewhat like a mouse, which I believe was (`Stuart Little' author) E.B. White's quote,'' said Dykstra. ``But we didn't want to have a mouse with a little boy's head on it. It's like trying to design a movie star by starting with his face.''

A series of sketches by Imageworks designers led to somewhere between 30 and 50 clay models of various possible Stuarts, with the final few candidates laboriously digitized into the computer with special penlike devices that map the contours of a 3-D object. Once the models had become digital, they were further tweaked to get the final details right.

``You try to find the appropriate blend,'' Minkoff said. ``He's not really a mouse. He's very skinny. Are Stuart's eyes realistic?''

That last is a big question, because mice don't have irises. And trying to show expressions, and the direction of a glance, are much more difficult artistically without a little thing like a pair of irises, Dykstra said.

``When he looks, how would he get directional sight?'' Dykstra said. ``There was a huge requirement that the character have subtlety, because he has a form that people have familiarity with. All his emotions have to come across in body language as well as facial features.''

That meant there were dozens of other considerations, as the designers tweaked Stuart's appearance from many angles, with many expressions.

``He had to look good from the front when he smiled, and from the side when he smiled,'' Dykstra said. ``We would turn him in profile and say, `Oh, my God, he looks like a bear!' You take the character and put him through his paces in one version, then repeat yourself. He was very much created like a traditional animation character. They run a cycle, change leg lengths and run the same cycle again.''

They used the relatively new 3-D animation technique of inverse kinematics to keep the character from looking, in Dykstra's words, ``too cartoony.'' IK essentially creates an internal ``skeleton'' based on a series of rules guiding how body parts move. That skeleton limits the range of motion of, say, the elbow as it interacts with the shoulder and wrist.

And getting details such as the eyes and body movements right were only part of the challenge. The creators also had to develop software that renders Stuart's fine white fur and whiskers convincingly, and hangs appropriately textured clothing on him. And to add to the challenge, the software had to create fur that looked wet, that sticks up like the hackles on a dog, and that ripples in a breeze.

After all that, there came another challenge: dropping the character into a scene and lighting him correctly. The computer-generated character has to show the reflected light from all the real-life objects in the scenes in which he is inserted, and in turn, his reflection has to show on all those objects, Dykstra said.

The resulting set of calculations can be dizzying to figure out and fill in, but without that work, a viewer's eye can tell something doesn't look quite right, or believable, Dykstra said.

But what's great about ``Stuart'' is that it does look believable. The film's biggest achievement is how easy it is to accept him as a real, if sometimes too sweet, character.

``What I like about the technology in this film is that it was all used in the service of something warm and real like this mouse, not some spaceship,'' said actress Geena Davis, who plays Stuart's mother. ``Little kids will think it's real.''

CAPTION(S):

4 Photos

Photo: (1 -- cover -- color) One small mouse, one giant leap for animation

Columbia's `Stuart Little' moves computer generation to the next level

(2) Sony Imageworks created more than 30 clay models for Stuart, then digitized the final candidates.

(3) The seamless transition from live action to computer generation allows Geena Davis to kiss Stuart.

(4) 'Stuart Little' is a mostly live-action film, features actors - including the family cat - interacting with a computer-generated mouse.