Welcome to the World of High Definition


I have mentioned a number of times before how excited I am about High-Definition-TV (HDTV) technology, and that is why I am truly delighted to present this month's issue to you, which was guest-edited by renowned scientist and inventor Bernard J. Lechner. Bernie is not only widely known for his work in television systems but also for his early innovations in active-matrix addressing of liquid crystals (LCs) for TV display applications in the mid 1960s. This is more than 20 years earlier than most of us can remember seeing LCDs in widespread use. Because of his unique vision and experiences in display technology, Bernie has lined up a great set of articles addressing the state of the art in HDTV. I hope you find them as interesting as I did.

And while we're on the subject, one of the most common criticisms I hear about HDTV, at least in the U.S. market, is the lack of real quality content and available channels from most cable and satellite providers. But both the availability of HD content and ways to receive it are finally improving. Until recently, if you were one of the lucky ones, blessed mostly by geography and a willingness to setup an antenna, you could already have been receiving as many as 8 –10 local terrestrial digital TV channels, many of which had at least some true HDTV content available. However, usually only evening network programs and movies were available in HD formats because the local stations did not have the infrastructure to produce true HD programs on their own. For most of the rest of us that have relied on cable or Direct Broadcast Satellite (DBS), the number of HD channels has been so limited that the shortage of programming almost hardly seemed to matter. In part, it looked to me like a '"chicken and egg'" problem. The cable companies have complained that there are not enough HD channels available to warrant the re-allocation in bandwidth and investment, while at the same time the producers have complained that there are limited delivery options for HD programming making it hard to justify the investments in infrastructure.

It now looks like the impasse is rapidly dissolving and both sides are working together to get as many new channels up and running as they can. Over the past 18 months or so, the situation has really begun to change. Local metropolitan newsrooms and production studios in most major TV markets have finally upgraded to HD equipment and are producing numerous local and regional programs in HD format. Many national cable networks have finally launched HD versions of their programming, and they are being increasingly carried by the satellite and cable providers.

If you subscribe to DBS, you may have recently noticed that both DirectTV and DishNetwork have expanded their HD channel offerings significantly. DirectTV is in the lead momentarily with its new satellite deployment, but DishNetwork is following close behind with its own bandwidth expansion plans. In most markets, if you subscribe to premium packages, you can receive as many as 50-plus channels with HD formats and content. Where fiber-optic services are being deployed by Verizon, I'm told that the HD channel offering is substantial as well. So, there no longer appears to be a shortage of ways to get HD content in most areas of the U.S.

However, not all HD is as it may appear. Even though a channel is formatted in HD, it may not be showing HD programming, or sometimes what appears to be HD content is really just a re-formatted and up-scaled version of standard definition (SD).

In their rush to deliver an HD program stream, some networks either pillar-box the 4:3 content, make up fairly meaningless extra content to surround the frames, or unnaturally stretch the original images. For example, the Weather Channel recently launched its HD feed to the satellite and cable providers. Unfortunately, its studio appears to produce live images with only a 4:3 aspect ratio, and the wider frame is utilized only during the local weather breaks for side-by-side information displays.

In other cases, the original program being presented is digitally enhanced and reformatted from 4:3 to 16:9 using various tricks that stretch or crop the frames without seeming to change proportion of the original scene. This is sometimes referred to generally as "anamorphic" scaling, although the movie industry employs a more strict and dissimilar definition of that term. The most frequent use of this approach can be seen on the TNT network, which has been nicknamed "Stretch-O-Vision" in numerous newsgroups and technology forums. TNT's approach is to stretch the image horizontally and progressively from the center to the edge of the frame until it fills the wide-screen format. The concept applied is that the intended primary attention point of the frame is usually in the center, while the perimeter is usually intended as background. In a scene involving a person standing in a room, the person is usually the central focus, and the proportions of the person are much easier to discern than those of the surrounding room. Therefore, stretching the edges of the frame should not detract much from the scene. However, while people in the center of the frame look normal, as they move to one side of the frame or the camera pans, they seem to gain significant body weight. Almost universally, I hear that viewers find this annoying and unflattering to the programs.

Nonetheless, the days of HD content are finally here, and there is much rejoicing in the retail world. The Insight Media Large Display Report, citing data from Displaybank, forecasts that new television sales are expected to hit 196 million units worldwide in 2007, up from 192 million units in 2006. But the mix is changing rapidly from 134 million CRT TVs last year to less than 110 million CRT units this year. Sales of LCD TVs, meanwhile, will almost double in 2007 and cross 100 million units sometime in 2009. I see this as a positive indication that content is now helping consumers justify the switch to larger-sized high-definition formats. The investments in these products are finally beginning to pay off, and hopefully HDTVs will finally become regular purchases instead of luxury items.

As usual, if you have comments on this or any other topics from the pages of ID, I invite you to share them with us at press@sid.org. I wish everyone reading this issue peace and prosperity as we approach the holiday season in most parts of the world.

Stephen P. Atwood