Say hello to virtual humans

Long considered an ivory-tower technology, virtual reality (VR) is beginning to fulfil its promise. VR tools are becoming accessible to everyone, thanks in part to hardware and software advances driven by the computer gaming industry. The result is mainstream-applications that range from entertainment to information delivery and even medical rehabilitation.

“Virtual reality technology has progressed considerably over recent decades,” says Hungarian-born Dr Barnabás Takács, founder/President of Digital Elite (Los Angeles) and founder/CTO of Digital Custom (San Francisco). But to date only Hollywood film studios and big-budget military research laboratories have truly benefited from VR. More recently, car makers have used it to visualise new vehicles before production.

Ready to roll

Why has VR not met early expectations? “New technologies often take 20 years to mature. Then people get realistic and industry starts to take them up,” says Takács, who has a background in many fields linked to VR. He adds that the main tools – such as head-mounted displays and feedback devices – have been in place since the 1980s. But these have been too costly to roll out to consumers.

VR hardware prices are now dropping, on the back of the booming computer games industry. For example, a head-mounted display costing several thousand dollars five years ago can now be picked up for just several hundred. Powerful computers with plenty of memory have also become commodity items, doing away with the need for expensive and customised VR platforms. Most modern PCs, including laptops, are more than sufficient to run real-time VR modules.

There have been other notable advances. Realism is getting better, especially thanks to the use of image-based modelling. And professional animation software, so vital for creating the impression that a virtual character is alive, is available to anyone willing to spend a few thousand dollars.

Self-expression

Animation is an area that Takács knows well. In 1999, he helped to develop a system that produces photo-realistic human characters for TV and movies, including a 30-second commercial that brought Marlene Dietrich back to life. He calls these characters “virtual humans” and predicts a big future for them. Traditional avatars, he adds, are just “lame representations of humans” and should not be confused with virtual humans. The latter have more facial expressions and it is possible to control and measure their movements.

“Cartoon characters can indicate emotion,” he says. “But high-resolution virtual humans have a face made up of as many as 100,000 polygons, far more than avatars.” Virtual female characters, for instance, have been around since 1996; but they often resemble one another and feel unreal. “My companies scanned many faces – up to 60 different expressions in 3D – to build the expressions of our virtual humans,” he continues. Our scanned database consisted of many different people, young and old, and both sexes, as well as their mannerisms. Given sufficient numbers of people, these expressions can be generalised and reapplied to a face.”

Even small differences, such as the speed of a blink or smile, can give a completely different feel to a virtual character. Eye gaze is also very complex, varying according to whether someone is listening or talking. Most avatars, however, have very stiff eyes and just look at one point.

Creating empathy

Extra detail like this allows the faces of virtual humans to show subtle expressions. He admits that this realism is not always necessary. But subtle expressions are vital for applications that mimic human communication – creating a link between a virtual human and a person. Adds Takács: “Synchronising their expressions and dialogue means we can create empathy, paving the way for educational applications, among others.”

Therapy is a rising star in the world of VR applications. A number of European IST projects (VEPSY, VREPAR and VREPAR2), albeit on a small scale, have successfully explored the use of personal computer-based virtual reality environments to clinically assess and treat anxiety disorders and specific phobias, such as fear of flying.

The use of so-called cybertherapy, which gently allows patients to ’experience’ distressing environments, is today common in California, in the United States. “VR can lead to significant cost savings in rehabilitation,” says Takács. “This is a good business to be in, whether for private insurance or national healthcare. It’s in the interest of society to treat these people and rehabilitate them faster.”

Portability is also important. Travelling doctors can take VR equipment around with them and do sessions in people’s homes. Also crucial, in his view, is the use of an open platform: “All tools must be kept open to extreme degrees, because people will want to use them in new ways.” His companies call on the Nebular open-source engine.

Lots of learning/b>