High-definition television is here to stay

It's here. If you haven't noticed, you haven't been in an electronics store for months. It's here, and it's going to get more here in a hurry, so you might as well tune in.

It's high-definition television.

How is it different from the set you've been using for years?

First, the picture is brighter, has more details, and is more like movie proportions. The picture will be wider, eliminating the need for TV stations to crop off the image on each side.

Second, it will have digital sound, better sound than what comes out of the tiny speakers that come with most TVs.

Third, the colors will be more vivid.

Right now, the rush is on for HDTV sets. The display of them at Costco, for instance, is dazzling. Price doesn't seem to matter. A Sharp 20-inch LCD display goes for about $700. Go up to a 37-inch Westinghouse LCD, and fork over $1,650. Go big for a Sony Grand Wega LCoS, and take out a loan for $4,750.

Sit back and enjoy.

But the technology gets pretty complex in a hurry. After scrolling through the Web on the subject of HDTV and reading "Popular Mechanics," I was able to grasp a modest knowledge of HDTV, but I'm not sure it's worth the effort if you just want to get the best picture for your pad.

Most of the satellite systems and DVDs use a digital-encoding scheme that provides a much clearer picture. For the standard TVs, the digital information is converted to the analog format by a device to display it on your analog TV. The image looks great, compared to a VHS tape, but it would be much better if the conversion to analog didn't happen.

HDTV is the transmission of pure digital television signals to display signals on a digital set. The digital signals may be broadcast over the air or transmitted by a cable or satellite system. In your home, a decoder receives the signal and uses it, in digital form, to directly drive your set.

HDTV is high-resolution digital television combined with Dolby Digital surround sound.

Of the 18 DTV formats, six are HDTV formats, five of which are based on progressive scanning and one on interlaced scanning. Of the remaining formats, eight are SDTV, and the remaining four are video graphics array formats.

The formats used in HDTV are:

• 720p - 1280x720 pixels progressive

• 1080i - 1920x1080 pixels interlaced

• 1080p - 1920x1080 pixels.

The figures refer to the number of lines the set projects on its surface. The new lines show a lot more pixels (dots that create the picture) than the 480 lines you see on your old standard TV - the more lines the better. Progressive scanning shows the whole picture, every line in one showing, every 60th of a second.

Broadcasters are having to squeeze the increased picture detail and higher quality surround sound into the same 6-megahertz (MHz) bandwidth used by analog television. Compression software, very similar to what is used in personal computing, allows this to happen.

Digital TV relies on a compression and encoding scheme known as MPEG-2 to fit its stunning images into a reasonable amount of bandwidth. In each image, the MPEG-2 software records just enough of the picture without making it look like something is missing. In subsequent frames, the software only records changes to the image and leaves the rest of the image as-is from the previous frame.

The FCC mandate affects broadcasters, cable companies and consumers in significant ways:

• Consumers have to buy new equipment, either a TV-set top box (to convert digital signals to analog signals) or a whole new TV set.

• Broadcasters have to spend lots to switch to DTV.

• Cable operators have to convert all of their equipment and all of their set-top boxes.

The station decides which DTV format it will transmit. A clear pattern has yet to emerge in the industry. The old TV has an effective picture resolution of about 210,000 pixels. In the highest-resolution digital TV formats, each picture contains about 2 million pixels.

The typical TV show uses 35mm film. In the case of film, the broadcaster converts it to an analog TV signal for broadcasting.

Right now, there isn't a great deal of programming broadcast in HDTV. Eventually, however, your current analog set will either have to be replaced or you will need to buy a set-top box for converting the digital signal.

Be sure any HDTV television receiver you purchase has input jacks that match the connectors on your VCR, cable box, DVD player and video game console. At the moment, there are no "standards" for what connections will appear on the back of an HDTV set.

Many early purchasers will have to "go back" to a traditional antenna to receive the over-the-air HDTV signal. The HDTV transmission system uses digital channels. You either have a picture, or you do not - there cannot be a snowy image with digital technology. There also will not be any "fringe area" reception.

HDTV conversion will be a process that unfolds over several years. Major networks still have to agree on what resolutions they will use. There is no FCC mandate on resolutions for the networks to follow. However, the ultimate destination is a significant advance - remarkably better pictures and sound for both your television and your computer.

As much of the programming sent out by networks still isn't HDTV, you may not want to rush into buying the gear. After all, no matter how high the definition, it's still the same old shows.

-- Contact reporter Sam Bauman at sbauman@nevadaappeal.com or 881-1236.

The local scene

So far, much of what is broadcast digitally by the Reno stations is not true HDTV. Four network stations have a digital channel, found at 2.1, 4.1, 8.1 and 26.1, which greatly enhances the picture but is not necessarily high definition. It depends on the content being broadcast.

Depending on your location, the VHF stations - 2.1, 4.1 and 8.1 - can be tuned in with a simple rabbit-ears antenna. The UHF station, 26.1, is a bit trickier.

Users of satellite systems such as DirecTV and Dish Network don't get them through their dishes. They need a separate antenna.