The future of television got a test-drive recently in
New York City. While consumers around the globe are just
now getting acquainted with the vivid picture quality of
high-definition television, or HDTV, a far more advanced
super-high-resolution system is in the works. NHK,
Japan's public broadcaster, is working on what it has
dubbed Super Hi-Vision: a TV technology—not expected to
be commercialized for a decade or more—that produces
live video with a resolution 16 times that of today's
HDTV and twice that of 70-millimeter movies. The New
York City test was recorded for display at a convention
of broadcasters who were meeting in Las Vegas.
Last November, NHK conducted its first live test in
the field, when it transmitted an uncompressed
24-gigabit-per-second SHV video signal for several
hours, producing a picture with a resolution of 7680 by
4320 pixels. The live video was relayed over 260
kilometers of optical fiber and viewed on a screen
measuring 10 meters by 5.5 meters. The transmission also
included a technically swank audio scheme, with more
than 22 channels, to match the video's high resolution.
To shoot the live transmission, the researchers used two
custom-built cameras equipped with four 8-megapixel CMOS sensors.
Months before, NHK had shown off an 8-minute SHV
video to visitors at the 2005 World Expo held near
Nagoya, from March to September last year. After
postproduction the movie weighed in at 1.4 terabytes and
had to be stored on a hard-disk array.
"The typical reaction of the audience was 'Sugoii!'
('Wow!')," says Masaru Kanazawa, a senior researcher
engineer in NHK's Science & Technical Research
Laboratories, in western Tokyo. He says some 1.6 million
Expo attendees watched the video, and many were
astonished with the heightened sense of reality it
evoked. He attributes this in part to the video's
clarity; the system's wide viewing angle of 100 degrees,
as opposed to HDTV's 30 degrees and the 15 degrees for
standard television; and the advanced audio system.
"They felt they were a part of the same scenes," he says.
Despite making such technological progress, NHK's
researchers are quick to caution that commercialization
of SHV is years—and maybe decades—away. And there are
lots of technical and political hurdles left to leap.
For instance, the company is working to have the format
accepted as an international standard by the
International Telecommunication
Union-Radiocommunications, which regulates radio
spectrum. If an agreement is reached, Kanazawa says the
proposed standard could be published as early as this
year, and then member countries would get to vote on it.
Perhaps a much greater hurdle SHV faces is further
developing the technology so that it can be used for
broadcasting. Because of the huge amount of data
involved, today it only works over optical fiber. But
NHK is looking to one day transmit it via satellite in
the 21-gigahertz band range. To do this, NHK's
researchers will likely need to come up with some form
of algorithm-based digital compression that will bring
the data rate down from 24 Gb/s to a somewhat more
manageable 200 to 400 megabits per second.
Of course, none of it will matter unless consumers
have affordable displays that can reproduce the camera's
high resolution. And broadcasters need the cameras to be
less complex as well as smaller. Given such obstacles,
NHK is targeting 2025, the company's 100th anniversary,
for the actual commercial launch of SHV.
[Editor's
note: Technical reasons prevent the
proper display of the high-resolution digital images
from NHK's new Super Hi-Vision TV camera. We
apologize for any inconvenience.]