Leonardo Electronic Almanac,
Vol. 9:5,
MIT Press
May 2001
VR Today
By Michael Naimark
I never liked the phrase "virtual reality".
For one thing, it immediately spawned the phrase "really real".
(Jaron: "Look! This new graphics engine makes these virtual worlds
look really real." Me: "What? It's a friggin' cartoon.") To
Jaron Lanier's credit it was the promotion of VR's "realness" that
provoked community consciousness to imagine what immersive virtual
environments could be. The down side, of course, was that such promotion
- some would say hype - led to grossly mismatched expectations between
the dream of VR and the actuality of what was technically possible.
For those of us working in the trenches, it was a mixed blessing.
Ten years ago, VR rocked. It was everywhere.
Jaron, who coined the phrase "virtual reality," was on the front
page of the Wall Street Journal. Marvin
Minsky, co-founder of MIT's Artificial Intelligence Lab, spoke
at Ars Electronica on the topic. Timothy Leary came back (actually
was sort of adopted by the VR community, and bless him, added a
brilliant mix of insight and outrageousness). Corporations,
particularly Japanese ones, announced major VR initiatives.
VR goggles and gloves became a fashion statement. " Cyber-sex" (a
phrase even more oxymoronic than virtual reality ) was seen in supermarket
tabloids and discussed at art openings.
Then what happened? It seems as if VR bit
the dust as fast as it rose to fame. Corporate VR labs, particularly
at Sony and Fujitsu, shifted focus. Many of the first VR companies,
including Jaron's VPL, folded. The great orators moved on.
The spotlight had shifted.
This was around 1992, and - no surprise here -
the spotlight had shifted to the Internet and the Web. This
is significant, and I'd like to offer some observations and speculations.
First, VR isn't dead, and with the spotlight off
it, more serious and focused work has been able to proceed unhampered.
Head-mounted displays - the goggles - have gotten higher resolution
and lighter weight, with promising work on "virtual retinal displays"
led by the HIT Lab
at the University of Washington. Fakespace Labs, a first-wave
VR company, is doing well building innovative immersive viewers
and screens. Tracking technology - the gloves - has miniaturized
and diversified, with tracking devices integrated into every human
appendage, prosthetic, and tool imaginable (a charge often led by
artists). There's some excellent work in this area continuing
at the University of North Carolina. "Image-based modeling"
and "light fields," recent sub-disciplines of computer vision, have
transformed the range of 3-D computer models from built-from-scratch
to camera-based, led by landmark work at Stanford, UC Berkeley,
and MIT. And in a most-forward thinking way, the artists and
scientists at the Electronic Visualization Lab of the University
of Chicago invented the "CAVE,"
an immersive projection space for group viewing capable of live-networked
applications.
The much-quoted 1965 decree of Ivan Sutherland
articulated the original dream of VR: "The screen is a window through
which one sees a virtual world. The challenge is to make that world
look real, act real, sound real, feel real." Ten years ago,
this was the world of eyephones and datagloves; of SGI Reality Engines
and high-level modeling languages; and of flight simulators and
location-based theme park attractions. Today it's postage-stamp-sized
silent images of Jenni-cam and the Western Wall, updating (on a
good day) at one frame per minute. But wait, you may say,
it's even more real because it's live and it's interactive.
Clearly, realness means different things to different people.
Let's look at the numbers, using moving images
as a frame of reference. I believe there are five distinct
levels, each with its own distinct industry. The hottest one
right now is the lowest-resolution one, the "streaming video" level,
since everyone wants video over the thin pipe of the current Internet.
Streaming video often has to pass through a 56 kilabit per second
modem, and is rarely more than 1 megabit per second (mb/sec).
But streaming video never looks as good as the movies we rent on
VHS. VHS quality, and home video in general, is the next level.
VHS resolution is approximately what the MPEG-1 standard is, with
a bandwidth or bitstream of 1.5 mb/sec (originally for CD video).
It's noteworthy that moving from streaming video to home video crosses
an industry line from computing and networks (Apple and Akamai)
to consumer video (Sony and Blockbuster). These people drink
in different bars.
The next level is broadcast-quality video.
MPEG-2 was made for this, with a bitstream range from 4 to 9 mb/sec.
Everyone agrees that broadcast video looks much better than VHS,
and high-end broadcast equipment typically costs ten times more
than consumer video equipment. Uncompressed broadcast video
often travels around production studios at 45 mb/sec. Then
there's cinema. The silver screen of the local movie theater
appears much bigger than the television in the home, and requires
that much more bandwidth. We just crossed another industry
line from video to filmmaking, from CNN to Panavision. Typically,
movies are shot with 35mm motion picture film, but the quest to
replace film with high-definition digital video has its roots almost
20 years ago. Today, various digital HDTV bitstreams range
from 20 mb/sec for highly compressed HDTV to as high as 1,000 mb/sec,
1gigabit/sec!
But we're not done. "Special venue" cinema,
the sort of immersive movies seen in theme parks and world's fairs,
are typically 10 times the bandwidth of theatrical 35mm film.
This is yet another industry, with formats like Imax (wide 70mm
film), Showscan (70mm film at 60 frames per second rather than 24),
Stereo-70 (twin 70mm film for 3D), and CircleVision (nine 35mm screens
in a panorama), each presenting different offerings of what's "really
real."
So the range of current versions of moving images
is from roughly 0.1 mb/sec to 10,000 mb/sec. It's both true and
ironic that the Real.com folks and the Imax folks, or the QuickTime
VR folks and the CircleVision folks, have very little to talk about.
But when one looks at the continuum, the drive at each end becomes
clear. At one end is sensory verisimilitude. Some might say, "looking
real." But others might say "dead," in that it's never live and
at best barely interactive. At the other end is "live," telematic,
participatory, and interactive, even if the cost is sacrificing
a four-story high 3D screen for a postage stamp screen. Again, realness
means different things to different people.
There's a noteworthy other phenomena, dealing
with the politics of access, best summarized by French art theorist
and UNESCO Webworld Director Philippe Queau: "Maximum hits per bits."
Its extreme interpretation is that there's something unfair about
concentrating a large number of bits for a small number of people.
Immersive theaters and art installations are out, websites accessible
to all are in. The reason is beyond theory: 53% of the world
still hasn't made a phone call.
Incredibly, this polarized situation is temporary.
Add Moore's Law and optical fiber, easily capable of over a million
mb/sec (!), and the conflict disappears. It's inevitable, with the
only questions being, when and how? The lever is large because the
status is embryonic.
Here are some examples of interim strategies doable
today. One strategy is simply to continue doing what we can
with the narrow pipe of the Internet. It's relatively cheap,
easy, and uncharted (particularly when one ponders the World Wide
part of the Web). And the pipe is quickly getting wider via
DSL, cable modems, and broadband.
Another strategy involves hybrid investigation.
For example, there are lots of stereoscopic and panoramic images
on the web, even if they're small. "Interactive films" have
existed since 1967 and have managed to present at least the illusion
of control. For example, the world's first interactive movie, at
Expo '67, involved red/green pushbuttons for everyone and two projectors
running in sync, where the operator swapped the lens cap depending
on the vote. Its director, Raduz Cincerra, alive and living in Prague,
told me "I did it as a joke but everyone believed it."
A related strategy is based on simulation: making
web video more cinematic in style and making motion pictures more
webcam like, for example. There's evidence of this happening
today. Another hybrid strategy exploits high-octane cheap
computers at each end of the narrow pipe. We're beginning
to see examples of the Sony Playstation II, whose power is similar
to the SGI Reality Engines that drove first-wave VR, being used
for live-networked gaming and beyond.
A most intriguing strategy turns the access
argument into a feature. One can use democratization ideology
to justify piping 100 times the bandwidth available for one person
into a collective space designed for 100 people (whatever the scale).
Public space as public research as public spectacle as community
experience. Such media-rich public experiments have a lively
history, most notably 100 years ago around the birth of cinema.
An enormous opportunity exists for museums, libraries, alternative
art spaces, and other public places to collaborate with scientists
and researchers.
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