OTHER TECH

Q. I can't wait to hear an HDTV broadcast in Dolby Digital sound. Do I just need to hook up some speakers to my new digital TV to hear it in surround?A. While 5.1-channel Dolby Digital sound is part of the HDTV standard, broadcasters and other HDTV service providers don't have to use it. Many high-def programs are transmitted in four-channel Dolby Surround-encoded stereo, which is decoded by a Dolby Pro Logic processor. Some HDTV sets have Dolby Digital decoders built in, which means you'd only have to add surround speakers and a subwoofer to get 5.1-channel sound. But given the size and quality of the speakers in most TVs, the experience won't have the impact that people have come to expect from home theater. You'll be better off routing the signal through a Dolby Digital receiver hooked up to a suite of good home theater speakers.

Q. When will everything be broadcast in widescreen HDTV?A. Maybe never. But that's not necessarily a bad thing, since broadcasters can use a digital TV channel for a variety of purposes. For example, instead of transmitting one high-definition channel, the same bandwidth could be used to simultaneously broadcast several pristine standard-def channels - and a few local PBS stations have already done just that. In Los Angeles, for instance, KCET divides its digital signal during the daytime to broadcast three different programs: standard-def versions of its regular shows, the PBS Kids channel, and an educational channel. In the evening, it switches its entire signal over to a single HDTV channel.

Q.I keep reading about the need to protect digital broadcasts from being pirated. What will that mean for me?A. TV and movie producers worry that HDTV broadcasts of their works will be illegally distributed, violating their copyrights and depriving everyone who worked on the projects of their just rewards. To prevent this, most HDTV tuners and digital TVs will contain circuitry and use special connectors that make it impossible for certain digital programs to be copied. And the FCC has given broadcasters the right to implement a digital flag - electronic coding that will instruct future digital TVs not to allow flagged programs to be sent over the Internet. Also, cable-TV networks like HBO and the producers of pay-per-view events have been granted the right to restrict the number of times a viewer can record one of their shows. Under the agreement that established standards for cable-ready digital TVs, CableCARD-equipped sets will allow viewers to make at least one copy of a show broadcast on basic or premium cable, but distributors of pay-per-view programming can prevent any recording of their shows.

To prevent unauthorized copying, the electronics industry has also come up with the High Definition Multimedia Interface, or HDMI - a refinement of the Digital Visual Interface, or DVI, which is video-only and uses a larger, bulky connector. Because HDMI cables can carry both audio and high-definition video, eliminating most of the wires that clutter the backs of home theater gear, HDMI could become the de facto way to connect a digital TV, a set-top box, a DVD player, and a Dolby Digital receiver. However, HDMI's robust High-bandwidth Digital Content Protection (HDCP) and the uncompressed state of the video signals it was designed to carry make it virtually impossible to record high-def programming if you use those connectors. For that you'll need to seek out gear that also has FireWire (a.k.a. IEEE 1394 or i.Link) connectors.

If your digital TV doesn't have the new inputs and outputs, fear not. To ensure that current DTV owners aren't left completely out in the cold, manufacturers are likely to include high-definition analog inputs and outputs on their products for years to come.

Q. If I buy an HDTV today, will it be obsolete in five years?A. You'll still be able to use any set - or set-top box - you buy today five years from now. Even if it doesn't have the digital jacks and networking capabilities that will become common on HDTVs over the next few years, broadcasters are obligated to pass signals through every type of connector. One benefit of using the old analog connectors is that the equipment won't respond to any anticopying commands that are transmitted with the programs. To discourage piracy, cable and satellite systems could insert a digital flag that would instruct the receiver to reduce the resolution of HDTV programming sent to sets that have only analog component-video connectors. But the FCC hasn't yet decided whether it will approve such a move.

One thing that will change is the quality of the high-definition image. As Dr. Joe Flaherty, CBS senior vice president and high-def pioneer, says, "Today's HDTV images are the worst HDTV we'll ever see." So as good as it looks today, improvements in display technology will mean even better-looking HDTV tomorrow.

Q. Are there any high-def DVDs?A. Not yet, but they're on the way. HDTV signals require considerably more storage capacity than a standard DVD can provide. But two groups are developing standards for a DVD-Video-compatible high-def format that can record up to 3 hours of high-def images on 27-gigabyte discs that store almost six times as much data as a regular single-sided DVD.

Both standards record data using a blue laser, which has a higher frequency, and thus shorter wavelength, than DVD's current red laser, which enables it to burn smaller, tighter-spaced pits on a disc. The Blu-ray standard is backed by a number of major brands, including Hitachi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, and RCA, while Toshiba and NEC are developing a competing Advanced Optical Disc (AOD), or HD-DVD, standard. Sony currently markets a Blu-ray recorder in Japan and announced last September that it plans to introduce a Blu-ray player to the U.S. by Christmas 2005.

Q. When will I be able to buy a high-def camcorder and VCR?A. They're both already available. JVC's GR-HD1 HDTV camcorder ($3,500) records true, widescreen HDTV images onto standard MiniDV cassettes, while its HM-DH40000 VCR ($1,000) can record high-def programs on D-VHS format tapes when it's connected to an HDTV tuner via its FireWire port. There are also about 50 prerecorded high-def D-VHS titles, many of them major movies, available under the D-Theater umbrella.

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Eric Taub writes about technology and consumer electronics for The New York Times and other publications. He is the author of Gaffers, Grips, and Best Boys: Who Does What in the Making of a Motion Picture (St. Martin's) and contributed to The New York Times Circuits: How Electronic Things Work (St. Martin's).