As recently as four years ago, Super Hi Vision was viewed with skepticism by a broadcast community that was still in the early stages of rolling out high-definition systems. With a resolution 16 times greater than HD, Super Hi-Vision (SHV) was perhaps seen as nothing more than a curious and futuristic experiment with little chance of developing into a workable broadcast model.
The eyes of the world were opened wide in 2008 when Japan’s public broadcaster NHK, the driving force behind the concept, chose the IBC convention to demonstrate the extent of its achievements. The first live SHV pictures were transmitted over fiber-optic cable from London’s City Hall to a special demonstration theatre at IBC in Amsterdam. A second feed was successfully sent from a server in Turin, Italy, by satellite.
This year NHK returned to IBC, again using the event as a public showcase for the technology’s advance and the results were impressive. The demo itself contained breathtaking live footage of central Amsterdam plus fresh images captured at the Tokyo marathon.
Equally important were the technological breakthroughs. In just two years the weight of the SHV camera had been halved to 20kg, making it a much more mobile recording tool. The prototype, one of only three in existence, was shown fitted with three (RGB) 1.25-inch 33 megapixel (8K) resolution sensors and sporting high-precision lenses, each with a basic 10:1 zoom. Since existing lenses are not sharp enough to capture all the information the SHV sensors can receive, NHK had them custom made.
The system also had a new compression scheme, which slashed data rates from 650 Mbps to below 350 Mbps. That’s still far above the goal of 150 Mbps, which would be at the outer reaches of practical transmission by super-fast broadband pipes in 2020, NHK’s target. Nonetheless, it shows considerable improvement.
Kenji Nagai, NHK’s executive director of engineering, was present to announce that, with the BBC and Olympic Broadcast Services (OBS), SHV could even be tested on public broadcasts of the 2012 London Olympics.
“The BBC can provide support for the aspiration that we cover some of 2012 in SHV,” Roger Mosey, BBC director of London 2012 revealed at IBC. “It’s likely we’ll have a limited number of test screens, ideally a couple in London and others throughout [the United Kingdom], to show people the shape of technlogy to come. It relies on us working with OBS to put SHV camera’s in the select venues.”
Less than two weeks later and the world’s first SHV transmission over IP networks was conducted at BBC TV Centre by BBC Research & Development in collaboration with NHK.
“The real challenge, and the real reason for the test, was to prove that we could transmit the signal live halfway round the world and if we could do that, that we could do it anywhere,” explained John Zubrzycki, BBC R&D principal technologist.
The trial proved that SHV could be carried over the Internet as a contribution signal from an event to the broadcaster’s studio, avoiding the expence of a satellite transponder and with an eye to IP as the way images will be transmitted in future.
NHK believes the format is suitable for sports, theatre, nature and travel productions and that, by panoramic views with fixed wide-view angles, it can create new types of content provided new production techniques are evolved.
“Gentle camera pans are manageable but the 100-degree viewing angle and ultra-sharp image mean that fast zooms are not advisable,” said Nagai. “Sudden cuts also need careful thought.”
Tests at IBC, the BBC and future Olympic trials are designed to stimulate interest within the industry and demand outside of it.
“The most important thing for us is to make people recognize that SHV will bring such a wonderful future,” says Keiichi Kubota, the director general of NHK R&D, noting that the Kyushu National Museum in Fukuoka has already introduced an SHV system. “Our final goal is still SHV broadcasting to the public, but before that, we have to put SHV to practical use in theatres.”
The SHV camera’s light sensitivity remains the key hurdle to overcome at the acquisition end while the BBC is contributing to developments in generating higher frame rates than the system’s current 60 fps.
“With movement in the scene, at higher resolutions, the picture will look blurred but if you increase the frame rate you increase sharpness,” says Zubrzycki.
You can expect these developments to get their premiere and rigorous examination in front of the world’s most senior engineering experts at IBC in future – and probably sooner than you think.
