|Beauty may be in the eye of the beholder, but it would be a mistake to assume that our notions of human beauty are completely subjective. Though exceptions exist, people tend to agree about who's attractive. Hundreds of thousands of Web hits each year, for example, demonstrate that there's something special about tennis player Anna Kournikova—and it's probably not her backhand. What is it about certain individuals that makes our hearts go pitter-pat? In a word, it's symmetry. According to recent studies on the subject of human attractiveness, those people whose faces (and bodies) are the most symmetrical are the ones we find most desirable.
A chance conversation with actor Marlon Brando several years ago introduced veteran CG filmmaker Scott Billups to the idea of symmetry as beauty, and started him on the road to his current Faces project: a digital couple whose features are modeled from those of Hollywood's most attractive stars. Each character has a particular actor's nose, another's chin, another's eyes, and so on. Using digital tools, Billups morphed together these features as symmetrically as possible. The resulting CG man and woman look somehow familiar, yet not really identifiable. These designed-for-appeal digital characters not only re-semble Hollywood stars, they're poised to become stars in their own right, as Billups plans for them to take on their first acting roles later this year.
|If "the Vitruvian Woman" looks vaguely familiar, it's because she's a digital composite of features from several popular actresses.
Billups has been creating virtual effects for film and broadcast for nearly 20 years. His credits range from previsualizations for Jurassic Park to digital soccer players for the recent Bend it Like Beckham. He's also a prolific creator of synthetic characters, having crafted more than 200 of them, including a digital Marlon Brando in 1990 and a CG Marilyn Monroe in 1994. It was while discussing Monroe with Brando, who had known her personally, that Billups began thinking about symmetry and beauty, and also hit upon an apparent contradiction.
"As we got into the actual features of Marilyn, we found that she was really odd," says Billups. "She had a little clown kind of bulbous nose, and her ears were enormous—they were a quarter the size of her head. She was very disproportionate." If symmetry equals loveliness, "how did this woman become a sex goddess, the icon of beauty?" According to Brando, this was because she was "a master of illusion," says Billups. Through makeup and other artifices, she could create the illusion of symmetry.
In the course of these conversations, Billups also learned about the Fibonacci numbers, a mathematical sequence (1-1-2-3-5-8-13...) introduced by 12th-century mathematician Leonardo Pisano Fibonacci. This sequence, in which each number is the sum of the two preceding numbers, appears in many different areas of mathematics, science, and nature. It even has its own journal, The Fibonacci Quarterly.
Most important for Billups's purposes, the Fibonacci sequence relates to the number 1.618, also called the Golden Mean, or phi. If you take the ratio of two successive numbers in Fibonacci's sequence and divide each by the one before it (1/1=1, 2/1=2, 3/2=1.5, 5/3=1.666...), the ratios eventually settle out at 1 to 1.618. (For more information about the Fibonacci sequence and how it relates to the Golden Mean, check out www.mcs.surrey.ac.uk/.Personal/R.Knott/Fibonacci/fib.html.)
Numerous examples in flora and fauna demonstrate the naturally occurring dimensional properties of the ratio 1.618-to-1. These include the distances between the spirals of a Nautilus shell, the arrangement of seeds in a sunflower, and the features of the human face. All faces adhere to this ratio, but the ones that do so most precisely are the ones we generally perceive to be most beautiful.
At the time of the Marilyn Monroe project, Billups hit on the idea of investigating the symmetry of beautiful faces, and representing them digitally. But the tools for a project of this kind did not exist in the mid-'90s. Less than a decade later, another chance conversation with some fellow Hollywood directors, and the realization that the proper tools were now available, spurred Billups to create what he's dubbed The Vitruvian Couple (after Leonardo da Vinci's famous drawing, The Vitruvian Man, which demonstrates that the length of a man's outspread arms is equal to his height).
Billups began with an informal poll among Hollywood directors. He created a Web page and a designated email address for the project, letting it be known that he was taking votes for the most beautiful features—not the most beautiful actors and actresses, but the most beautiful lips, noses, cheekbones, etc. belonging to actors and actresses. Billups reasoned that because directors spent so much time behind the camera, they, more than anyone, would have informed opinions about his subject.
Then he asked actors and actresses to participate in the voting process as well. Many voted for themselves, he notes, with one very famous individual voting for his own chin more than 100 times. At the height of the project, which went on for eight months, Billups was spending up to two hours per day going through emails related to the Faces project.
|Photoshop CS's file browser allowed Billups to view files as sizable images, not just as file names, and also to sort and edit images, using the dialog boxes to the left.
Billups started out charting the data on a spreadsheet in Microsoft Excel, then moved it to Adobe's Photoshop CS. The file browser features in the latest version of CS amount to what Billups refers to as "visual Excel." The browser allows users to view images in rows and columns of large-format thumbnails that can be scaled up to larger sizes if need be. Images are also editable with regard to file size, history, category, and so forth, all within the browser, where they can also be grouped into categories and subcategories. "I basically built sub-bins of body parts," says Billups. "It was a little Frankensteinian."
These groupings allowed easy views of the features that were leading the pack—until a new set of votes would come in. "The leaders shifted quite often," he says.
Votes are still trickling in, but early this year Billups decided to tally the results and set about creating his ideal man and woman. Here again, the new Photoshop CS came in handy. "The texture map for the faces was huge—8000 pixels high by 12,000 pixels wide, with maybe 20 layers." With Photoshop and a dual-processor Apple G5 with 8gb of RAM, however, the files "just rolled around like nothing."
As he assembled the faces in Photoshop, Billups used a grid of two pentagrams (yet another manifestation of the Fibonacci sequence and the Golden Mean), one rotated over the other by 180 degrees. The resulting 10-pointed star contained intersecting lines that helped determine placement and relative distances between features.
The artist also relied on orthogonal photographs of the thespians in question. Here he discovered that Marilyn Monroe was not the only master of illusion in Tinseltown. "Most actors and actresses have a somewhat unflattering set of shots on file for makeup artists, prosthetics, and whatnot," he says. "You look at 'insert name of famous actress here' with makeup on standing on the red carpet, and then you look at the orthographic picture, and you say, 'Oh my goodness, it's not the same person.'"
Billups used Photoshop CS to work with skin tones across multiple layers, and employed the software's Healing Brush tool to blend between regions such as the eyes and cheeks. From Photoshop, the files went into Alias's Maya for 3D modeling, and then into Curious Labs' Poser, which Billups used for the majority of the project.
The nearly complete models are now being animated in NewTek's LightWave. Billups is using motion capture, which he prefers to other types of animation. "I'm not big on kinematics or physical driving. The people best qualified to articulate synthetic characters are computer operators. But are they the best people to evoke a sense of the dramatic? No. Mocap is the way you do that."
|A near-final version of the "perfect" man, complete with modern hair, is shown at left. An overlay of pentagrams helped Billups symmetrically position facial features on the woman's face at right.
So who are the Vitruvian Man and Woman modeled after? Who has the most beautiful eyes, ears, chin, etc. in the business? Unfortunately, for legal reasons, that's a secret for now. However, two of the winners are so obvious, says Billups, that he thought he may as well divulge them: The Vitruvian Man has Brendan Fraser's mouth, and the Vitruvian Woman, Michelle Pfeiffer's mouth. Brooke Shields was the top vote-getter overall, but not a winner in any single feature category.
Billups plans for the couple to debut in his own short film, "Mid Century," which is due out later this year. The 30-minute movie is shot in high definition and stars Faye Dunaway and John Glover. "I'm going to try out the characters there, and I figure nobody can give me any grief for that." Afterward, the CG duo will make the circuit in Hollywood, "and if people ask me to put them in their movies, we'll see."
The "grief" Billups refers to is some consternation in the entertainment world over digital actors—with or without borrowed features—who are viewed as possible threats to the living, breathing variety. Digital movie stars wouldn't, for example, demand high wages, air-conditioned trailers, or imported water.
Billups claims that these fears are unfounded. In some cases—such as stunts—it's true that digital actors are being used in place of real people. But in general, he says, "it's always going to be cheaper to feed 'em [live actors]."
For example, Billups explains that it's easier and far less expensive to direct and film a live human walking through a doorway and stepping over a box than it is to have the same action performed in a motion-capture studio with specialized technicians operating the equipment. The resulting mocap data would then have to be resolved, rendered, composited, and so forth by ever more specialized artists and technicians.
At the end of the day, are Billups's digital man and woman the most beautiful individuals ever? Symmetry or no, the answer still seems to be in the eye of the beholder. A casual survey of the Computer Graphics World staff showed mixed results. Some thought the characters stunning. Others shrugged. Of course, it's not fair to compare digital characters or still imagery of any kind to living humans. After all, there's more to beauty than a 1.618-to-1 ratio—and Billups himself agrees with that. "True beauty," he says, "comes from the actions and the play of emotions across the face." So, until we find the mathematical ratios for those, we'll just have to rely on our instincts.
Jenny Donelan is a contributing editor for Computer Graphics World.