Source: Philips Research (ITU 010016)
Of the future industries now visible on the horizon, television has gripped the public imagination most firmly. To bring television to the perfection needed for public service, our work proceeds under high pressure at great cost. Such experiments call for imagination of the highest order and for the courage to follow where that imagination leads. It is in this spirit that our laboratories and our scientists are diligently and devotedly engaged in a task of the highest service to humanity."
From such work, television was born, says Joseph A. Flaherty, recalling this statement made by David Sarnoff on 15
June 1936, just two weeks before the first American experimental television transmitter went on-the-air atop the Empire
State building in New York. Mr Flaherty, who is Vice-Chairman of Study Group 6 of the ITU Radiocommunication Sector
(ITU-R) and Senior Vice-President for Technology at CBS Television, adds that "today, the same can be said of the
genius and dedication in the service of mankind that gave birth to digital television and HDTV".
For some, the future of digital tele-vision and HDTV began on 1 June 1990, when General Instrument proposed an all-digital HDTV system. For others, that future is about to begin, thanks to the adoption of the world's only digital HDTV production standard: ITU-R Recommendation BT.709. This ITU standard is based on a high definition "Common Image Format" (HD-CIF) of 1920 pixels-per-line at an aspect ratio of 16:9 with 1080 lines-per-picture progressively scanned at 24, 25, and 30 frames-per-second and both interlaced and progressively scanned at 50, and 60 pictures-per-second. Version 4 of BT.709 was approved by the World Radiocommunication Assembly in Istanbul in May 2000.
How does HDTV differ from today's television?
For Mr Flaherty, the wide screen, high-definition television is not just pretty pictures for today's small screen television sets. Rather, it is a wholly new digital platform that will support the larger and vastly improved displays now in commercial development. "It is trite to say that people watch programmes, not technology. But lest you underestimate the importance of your technical tools, consider that every element of every picture, every syllable of every word, and every note of every musical score must pass through this complex technology funnel on its way to the viewer," Mr Flaherty explains, highlighting the features that distinguish HDTV from what most people know today (see box).
Why is HDTV taking so long to reach the market?
Anthony Smith, Marketing & Communications, Digital Video Broadcasting (DVB), points to consumer misunderstanding of the technology. "We have consumers who see standard-definition digital television (SDTV) on flat screens and because of the great picture quality compared to analogue, they believe it is HDTV," he says. But that is not all. The high cost of consumer equipment, the lack of compelling programmes, the cost of establishing an HDTV transmission or play-out centre for broadcasters, and the impossible number of formats available under the American system are also to blame, Mr Smith remarks, adding that broadcasters would like HDTV because it captures or holds the spectrum that would otherwise be allocated or sold for other use — therefore it has become embroiled in politics. This will always kill a market.
Robert Graves, Chairman of the Advanced Television Systems Committee (ATSC) argues that HDTV introduction is not
necessarily slow, although it is slower than many people had anticipated. "Sometimes it is compared to the
introduction of the digital television service in the United Kingdom. But this is an apples-to-oranges comparison. In
the United Kingdom, the primary service that has been attractive to viewers is one that offers multiple channels of SDTV
for a monthly fee," Mr Graves notes, stressing that this is not an attractive option for US broadcasters, because
their viewers have had that option for many years, by either cable or satellite, for a reasonable fee. "What we are
offering in the US, among many other digital television options, is a quantum improvement in the technical quality of
free over-the-air television in the form of HDTV, and the single most important factor that has limited its acceptance
thus far is the current lack of ability to obtain HDTV programming over most cable television systems", he remarks.
Mr Graves is convinced that "if we had all of the major sporting events available in HDTV now, we would be selling millions of HDTV receivers, even at today's prices for receivers, which have fallen by about 50 per cent and are likely to fall another 50 in the next two years. Within five years or so, we believe that HDTV receivers will cost about the same as today's analogue television receivers of the same screen size. HDTV will rapidly become the norm for television viewing throughout the world, especially for sports and other popular programming. When you see sports in HDTV you never want to see them in standard-definition television again."
Another factor is the delay in working out copy protection schemes to protect content providers from piracy.
J. Kumada of Nippon Hoso Kyokai (NHK), Japan Broadcasting Corporation, and Vice-Chairman of ITU-R Study Group
6, puts HDTV's slow market uptake to the lack of a unified standard. "Manufacturers found it difficult to invest a
lot of money without a stable standard. But this has been resolved now", he says. Users, broadcasters, film and
programme producers alike, found it difficult to invest in what appeared to be a small market. Again, this has almost
been resolved, the cost of equipment is falling to regular equipment prices and the programme market is growing, at
least in Japan.
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Will the adoption of BT.709 bridge past regional differences and speed up market introduction of HDTV?
The Asia-Pacific Broadcasting Union (ABU) has adopted the 1080 CIF format as its unique HDTV programme production and international exchange standard for use throughout the Asia-Pacific region. Mr Kumada notes that the ITU standard provides a single unified picture format and sampling frequency while it supports several field frequencies. "This standard can be applied in any environment, 50 Hz in Europe, 60 Hz in United States and Japan, and 24 Hz in the film industry. The unique picture format and sampling frequency not only facilitate the exchange of programmes, even between different environments, but also make it possible to produce equipment that can work in any environment." The cost of HDTV cameras and VCRs is almost the same as that of NTSC equipment (about 20 per cent higher) and is falling rapidly. "I believe the HDTV market will increase quickly because ITU-R BT.709 works not only as the bridge between different regions but also as the bridge between all imaging fields, from tele-vision, film production to computing", remarks Mr Kumada.
Mr Graves agrees that "with digital technology, programme production, transmission, and reception and display can easily be separated, and BT.709 provides a common image format that will allow programmes to be exchanged easily throughout the world, without regard to the different digital transmission standards that are used in different countries and regions." This common image format will also help to speed up the introduction of HDTV throughout the world, because it will allow producers in every country to address global markets for their content. Even producers who live in countries that still have no plans for offering HDTV programmes can produce their content in HDTV, so that it can be shown in HDTV format in those countries that have already introduced HDTV services.
Mr Smith remarks that "the benefit of an industry standard is to create, in general, a single entity in a technological environment that will allow for the sharing of resources and in particular of content produced in the once fragmented analogue world of which we know so well." The jury is still out on the best format with respect to the modulation scheme and the Japanese have already tested and verified that 720P is the best compromise in a DTV world at least. Therefore the market does not agree with the Recommendation, which is predominantly geared towards a US environment and driven through ITU by the United States, Mr Smith remarks.
He adds that HDTV is a failure in market terms, at the moment, and will be in turmoil as long as the United States has issues about modulation systems and receivability. This leaves the content provider or producer between a rock and a hard place. Where does he or she find an outlet, not to mention the production cost? The ATSC tables have 28 different HDTV formats and therefore can comply with BT. 709. The other standards organizations, especially DVB, cover over 50 per cent of the population for the move to digital. The transmission is an agnostic pipe and therefore it does not need to know the bits and bytes and the make up of the signal, just the data rate.
So the present situation is one of business models. Will HDTV succeed? "Eventually is my answer but not in the short term. It has failed in the market-place twice, once in Europe with HD-MAC and now in the United States", Mr Smith states.
Who is using BT.709 in their systems and how many hours of programming are being broadcast in HDTV?
In the United States, BT.709-3 is based on the HDTV formats that are included in the ATSC Digital Television Standard that is now in use for terrestrial digital television broadcasts. The ATSC system is now operating at 166 television stations in 57 cities, reaching 65 per cent of US television viewers. So far, although all of the US television networks carry some HDTV programming, only one of them, CBS, has made a concerted effort to carry a substantial amount of HDTV programming. CBS is transmitting virtually all of its prime time evening programming in HDTV, helped in part by financial sponsorships from consumer electronics manufacturers. CBS is also showing selected major sporting events in HDTV.
ABC is showing at least two movies a week in HDTV. NBC is showing one late night talk show in HDTV and occasional sporting events or movies. PBS generally shows HDTV programming whenever its digital station is on the air, usually with an additional simultaneous standard-definition digital programme. In addition to these terrestrial broadcast efforts, both major DBS service providers in the US are showing some HDTV, generally one movie channel and one pay-per-view (PPV) movie channel, and a few cable systems in the US are showing HDTV programming. "All in all, there are more than 100 hours per week of HDTV available in most parts of the US, and much more if you count the movies available by satellite", according to Mr Graves.
In North America, as of 30 September 2000 about 530 000 consumers had purchased HDTV products. About 90 000 of these were either fully integrated HDTV receivers or set-top boxes that can be used with an HDTV-capable receiver. The remaining 440 000 were HDTV displays that must be used with a set-top box to receive terrestrial, satellite or cable HDTV programming.
"In Japan, we have just started a new digital satellite broadcasting channel, in which seven broadcasters serve HDTV programmes, all of which are produced using ITU-R 709-4 (1080/60-interlace)", says Mr Kumada. NHK broadcasts HDTV programmes 24 hours a day through this digital channel. These include news programmes that are broadcast in both HDTV and NTSC channels after format conversion. Nearly half of the news materials are shot with HDTV cameras. About two-thirds of NHK's studios in Tokyo have HDTV equipment that is used for either HDTV or NTSC programmes. For news gathering, HDTV equipment is used at major NHK offices, including overseas countries.
The Republic of Korea's public broadcaster, KBS, is also believed to be offering one hour HDTV service via a digital terrestrial channel. That country plans to broadcast the 2002 World Cup Football Games in HDTV.
In Europe, no broadcast systems are being implemented under BT. 709 "due to the fact that HDTV is not seen as a viable business model", remarks Mr Smith. Instead, "Europe is concentrating on mobile, portable, better coverage and interactive, enhanced and Internet on the tele-vision, deemed as a much more serious business model," Mr Smith adds.
DVD and SDTV are of such high quality that the consumer is taken aback at the enormous change from their analogue systems. HDTV will eventually have a market on cable and on satellite as PPV services that will allow for movies and sports and nature programmes. No programmes are being broadcast other than tests on cable and some satellite services — nothing to the regular public at this point in the market.
What does the future hold for HDTV?
Apparently, many American consumers are investing in HDTV displays to use with their DVD players and in anticipation of the availability of more HDTV programming. Set-top boxes that can receive terrestrial and satellite HDTV signals are now widely available for about USD 550, so we expect these people who already have HDTV displays to purchase them just as soon as more programming becomes available.
On the question of how HDTV receivers will fare, Mr Flaherty says "no one knows for sure, but public interest is running high for new and improved technology, and all the consumer research conducted in the United States by the Consumer Electronics Manufacturers Association (CEMA) indicates that Americans want HDTV. It is instructive to note the time taken from market entry to the sale of the first million units of other new consumer products."
It took colour television nearly nine years to sell the first million colour sets in the United States. It took the VCR nearly five years to reach one million sales driven solely by time shift viewing of broadcast programmes. The rental of movie cassettes came much later. The CD player required close to three years to reach the one million mark. The consumer interest was there, the technical quality was there, and the price fell dramatically during the period. CDs had to succeed. Lastly, the newest entry, and the fastest growing tele-vision consumer product, the DVD reached sales of one million in just two years. This product won on two counts: the technical quality was far superior to VHS, and, after only three months, the price was right.
In Japan, there are already about one million HDTV households "because we have been broadcasting MUSE-HDTV (an analogue ser-vice with digital assistance) for 10 years", says Mr kumada. In mid-December 2000, the number of digital HDTV receivers was 200 000 and was expected to reach about 300 000 by the end of that month. So, the number of households who receive HDTV was estimated to reach 1.3 million by year-end 2000. An additional 650 000 households have HDTV displays, albeit without digital/analogue decoders.
Japan Electronics and Information Technology Industries Association (JEITA) estimates the number of HDTV households in that country will reach 10 million within the next three years.