Monday, October 31, 2005

Eyes on the 1080p Prize

In the best of all possible HDTV worlds, 1080p would be a firm reality.

We would, that is, have TVs to which true 1080p source material could be input and displayed as such: video frames having 1,080 rows of pixels, each horizontal row containing 16:9 x 1,080 = 1,920 pixels.

A video frame? It's what you see when you hit pause on a DVD player, a single frozen image, with no movement. Moving video is really a succession of such frames, displayed one after another so fast that your eye perceives motion.

For 1080p reception, each 1,920 x 1,080 input frame of video would be received and presented fully intact, which is what the "p" (for "progressive scan") means. As transmitted, it would not be subdivided into two "i"-for-"interlaced" fields, with only the odd-numbered pixel rows present in field #1 and only the even-numbered rows, 1/60 second later, in field #2.

A pixel row is also called a "scan line." When the latter type of 1080-line scanning is done, with each video field containing only alternate scan lines, not the whole image "raster" at once, the transmission method is 1080i, not 1080p. 1080i scanning typically produces 60 fields per second, which comes to 30 frames per second.

Over-the-air high-definition television broadcasts use either 1080i or 720p: 720 rows of pixels, 16:9 x 720 = 1,280 pixels per row, progressive scan, 30 non-subdivided frames per second. 1080p is not supported over the air; it doubles the number of pixels transmitted per second by 1080i, requiring TV channels to hog unacceptably high bandwidth.

Unless ... a more efficient digital video compression scheme is used. At the time the standards for HDTV broadcasting were set, MPEG-2 was the best compression method around. Now we have MPEG-4, which squeezes digital video down far more compactly. We also have VC-1, based on Windows Media Video (version 9). Both are supported by the two emerging competitors for high-definition blue-laser DVDs: Blu-ray and HD DVD. Blu-ray and HD DVD could offer us true 1080p discs without paying a huge price in data rate or storage capacity.

The blue-laser DVD gurus, however, have as yet committed to no more than 1080i. For one thing, there are few if any TVs that can input 1080p — even though a number of new models can display it. (See, for example, Sony's Groundbreaking New SXRD RPTVs.) There seems to be no agreement on how to copy-protect 1080p, for another thing.

There are yet subtler problems. For example, true 1080p promises greater visual detail than merely "deinterlacing" 1080i would imply. But how to get there?

Most newfangled TVs need to deinterlace 1080i to some progressively scanned form — unless they are based on old-fashioned cathode-ray tube technology with actual scan lines traced out by an electron beam, that is. One conceptually simple form of deinterlacing is to "borrow" the pixel rows that are not present in a given field from the other field in the same frame. Another is to interpolate the pixels between those which are actually present: to "guess" what they would contain, if they were really there.

There are more sophisticated approaches. One of them is to notice that the video program originated in film, and use so-called 3:2 pulldown compensation. The TV figures out which other fields of which other frames really came from the same film frame — owing to the fact that film unwinds at a mere 24 frames per second, not 30 — so it knows how to fill in the missing pixel rows in a given field with total precision.

Unless deinterlacing can leverage such special knowledge as that, the interpolated or borrowed or calculated pixels constitute "false" information. What's worse, they don't really count as "new" information at all, for they don't contain any extra detail. For that reason alone, true 1080p can improve on the "false" detail present in deinterlaced 1080i quite considerably.

But there's another reason as well, yet more subtle, why we ought to prefer 1080p. In interlaced scanning, vertical resolution — the number of horizontal lines actually visible in the image — is reduced to avoid interline flicker.

So if there are 1,080 rows of pixels, there may be only 70% of that number of visibly distinguishable lines of image content: say, 756 lines of vertical resolution.

"When adjacent lines in the frame (which are transmitted and displayed one field-time apart) are not identical," says this web page, interlaced scanning will produce a flickering effect. If the field-time is 1/60 second, you can get a tiny detail (say, white) in the first 1/60 second that disappears (turns black) in the second 1/60 second. Enough of those details coming and going, and the display as a whole will have an annoying 30-Hz flicker.

That's bad, so the camera simply filters out the smallest details present in the vertical dimension of the image. 1,080 rows of pixels then produce only, say, 756 lines of vertical resolution.

But if you know the image is going to be captured, recorded, transmitted, received, and displayed at 1080p, you don't have to filter to avoid interline flicker.

Another thing 1080p offers is a way to avoid the 3:2-pulldown problem entirely.

When film at 24 frames per second is transferred to video at 30 frames per second, the film is "pulled down" — advanced — in a herky-jerky way such that some film frames contribute their visual information to three video fields, while other film frames contribute to only two video fields. That's 3:2 pulldown, also called 2:3 pulldown.

If such film-transferred video is not deinterlaced with totally accurate 3:2-pulldown compensation — TV user menus often call it "film mode" — then those video frames whose two fields come from two different film frames can produce "jaggies," or worse, on the screen. Fie!

1080p can avoid that problem entirely by recording video at the same frame rate as film uses: 24 fps. That way, there's a 1:1 correspondence between film frames and video frames. (To avoid the flicker sometimes associated with such a low frame rate, the TV can display each video frame three times in each 1/24 second frame time, for an effective 72 frames per second.)

In the real world, we don't even know as of now whether there will ever be any true 1080p DVDs, much less whether they will be made with all the vertical resolution 1080p "ought to have." They might be filtered in deference to CRT-based interlaced HDTV displays.

But we can always hope true 1080p DVDs are on the way, with no vertical filtering!

Monday, October 24, 2005

Waiting to Buy an HDTV? Smart Move!

Are you biding you time before investing in an HDTV? If so, you may be smart. As I mentioned in Sony's Groundbreaking New SXRD RPTVs, HDTV makers are improving the breed at a rapid clip just now. Not only has Sony just introduced a pair of attractive new rear projectors employing the version of Liquid Crystal on Silicon (LCoS) technology Sony calls SXRD, for Silicon X-tal Reflective Display, but JVC is also just entering the LCoS race with a vengeance.

Its 70FH96 rear projector is just about to hit the stores, says the Nov. 2005 Sound & Vision magazine (p. 26). This 70" 1080p behemoth, which sells for $6,000, is also an LCoS implementation, though JVC calls it D-ILA, for Direct-drive Image Light Amplifier. When it's high-def — and 1080p is the highest of high-def — JVC dubs it HD-ILA.

The same magazine also contains a blurb (p. 28) about Pioneer's latest plasma flat panels, among them the 43" PDP-4360HD for $4,500. These plasmas "boast better contrast than ever before," says S&V, mediocre contrast being one of the principal banes of plasma up to now, due to grayish black levels. The PDP-4360HD also has "multiple HDMI connectors" — so you can use more than one digital signal source without falling back on analog connections — "in a separate media box" — so you can make all external connections not to the flat panel itself, mounted on a wall, but to a separate box that connects to the flat panel by a small handful of two or three wires.

And if you realize you'll be needing a TV with a digital tuner one fine day but don't give a hoot about high definition, check out the blurb on page 20 about RCA's new digital standard-definition TVs. The 27" 27F634T, listing for $359, is shown. It has the "old-fashioned" squarish screen that we're so accustomed to and downconverts signals (including HD signals) to good old 480i, the "standard resolution for all analog signals." Translation: you can now spend what you've long been expecting to spend for a new TV — three figures — and get one that looks just like TVs of yore, in terms of picture shape and quality. But it's future-proof. It receives off-the-air digital broadcasts, so when analog transmissions bite the dust in the next year or four, you'll be ready even if you don't subscribe to cable or satellite TV.

Sunday, October 23, 2005

Looking Forward to High-Def DVD?

One of the hot topics these days in HDTV land is the imminent arrival of high-definition DVDs. There's a format war a-brewin', with two mutually incompatible versions on tap: Blu-ray and HD DVD.

These two camps have apparently stopped negotiating for a compromise solution to the forthcoming so-called "blue laser" DVD rollout which will allow DVD discs to hold far more programming than they do today. The smaller wavelength lets the laser zoom in on smaller, more densely packed specks on the disc's surface. Since high-def content uses up a lot more data, changing the laser from red to blue can enable DVDs to go high-definition.

You can get the full scoop in the just-published "Winter 2006 Buyer's Guide to Home Theater" from The Perfect Vision magazine. The article "High-Definition DVD is Coming" gives a rundown on the two technologies and lists the first titles that will be available when HD DVD launches next spring. (The launch is now expected to come in March '06, followed in April by the Blu-ray premiere.)

Meanwhile, the the Nov. 2005 Sound & Vision (p. 17) says, "So HD DVD and Blu-ray [with negotiations shelved] remain headed for a showdown. But wait, soap fans, there's a new cliffhanger: Samsung has just announced that sometime next year, it will market a machine that can play both formats."

(Note that both kinds of machines will play all standard-def DVDs, new and legacy, just fine. Standard-def DVDs will continue to come out in droves into the foreseeable future, no matter what happens in the blue-laser format wars.)

If there is indeed a dual-format, combo player in the works, that will soften the blow of a format war considerably. And it will concomitantly undercut the Nov. '05 Widescreen Review effort to boost the High-Definition Disc Consumer Advocacy Alliance. That loose confluence of movers and shakers in the world of DVD and HDTV consumers would like to burden video equipment manufacturers and Hollywood studios with a greater sense of resposibility than heretofore shown. Not only is the looming format war over blue-laser DVD a travesty, but other choices the two camps may be making might wind up "punishing the innocent for the sins of the guilty."

The "High-Definition Disc Consumer Advocacy Alliance FAQ" piece (pp. 80ff.) informs us that the analog component video outputs of the new DVD players may down-rez HD discs to 480p, the resolution now obtained with most so-called "progressive scan" DVD players. Blocking HD on analog would be done — if it is done — to foil piracy, since analog output signals are not copy-protected the way digital signals are.

The new players can also "revoke" their own ability to play the new discs. If the powers-that-be learn that a certain player (or is it player model?) has been modified to thwart digital copy protection, it will be identifed as beyond the pale by having its "encryption key ... placed on a revoked list and transmitted to players on newly released discs."

The article is unclear about this. On the one hand, "that player would then be unable to play all high-definition discs." On the other hand, "every single player of that manufacture and model number could find itself on the revoked list."

The article also mentions other ways in which the actual implementation of blue-laser DVD may punish early adopters of HDTV technology, whose gear might not work optimally with the new players and discs.

But future buyers of HDTV sets are probably fine, be it noted. As long as their sets support either a DVI or, preferably, an HDMI digital video input connection with so-called HDCP copy protection — assuming their DVD players don't get "revoked" — no problem. (All the same, it probably behooves one to have at least two such inputs: one for DVD and one for, say, an HD cable or satellite box.)

Thursday, October 20, 2005

Sony's Groundbreaking New SXRD RPTVs

The November 2005 issue of Widescreen Review contains a review (download it in PDF form here, if you are logged on to the site) of the hot new KDS-R60XBR1 HDTV from Sony. Sony's first SXRD rear projector, it produces true 1920 x 1080p resolution on a nice, big 60" screen for $5,000. Its little brother, the KDS-R50XBR1, offers 50" of widescreen 1080p resolution for $4,000. There is also a review, not yet online, of the KDS-R60XBR1 in the same month's issue of Home Theater magazine.

SXRD stands for Silicon X-tal (for "Crystal") Reflective Display. It's Sony's own version of LCoS: Liquid Crystal on Silicon, a type of microdisplay which has recently been seen in pricey front projectors but until now not in rear projectors.

As a microdisplay, SXRD creates its image on a small rectangular chip (or actually three of them, one for each primary color) about the size of a postage stamp. This little panel of pixels is made of a liquid crystal material, just as is an LCD (liquid crystal display) chip. But unlike an LCD chip, an LCoS/SXRD chip doesn't transmit light emitted from behind it. The light source instead reflects off an aluminized layer on which the pixels are more tightly squeezed together, to eliminate the so-called "screen door" effect wherein the LCD pixel structure presents itself to the eye.

Because the light passes through the crystal twice, not once, the contrast ratio is vastly improved, resulting in a bright picture with truly dark blacks. The structure of the chip also allows Sony to brag of lickety-split pixel response time, so moving elements of the image don't develop ghost trails.

Sony's LCoS/SXRD rear projectors compete directly with various manufacturers' (Samsung, HP, Mitsubishi) 1080p DLP-based RPs. Those sets use a trick to coax true 1920 x 1080p resolution out of a 960 x 1080p microdisplay chip. Texas Instruments, the originator of DLP, calls it SmoothPicture. Other folks call it "wobulation." A mirror in the projection path is pivoted ever so slightly to shift the image by one pixel horizontally, as each video frame is being projected. (For more on this, see An Eye on DLP, No. 3.) Critics say that produces eye fatigue. Sony's SXRD chips are natively 1920 x 1080, and no such trick is needed.

Bill Cruce's review of the KDS-R60XBR1 in Widescreen Review is a truly glowing one. In terms of picture quality, about the only minor flaw he cites is oversaturated green. Geoffrey Morrison in Home Theater is more guarded with his accolades, mentioning that both red and green were too strong in the unit he reviewed — though they are the correct shades of the respective hues. "So objects may look really green," he says, "but they're not greenish-yellow or greenish-blue like the colors that many digital displays can produce." But: "One side of the screen had a bluish-green tint [on test patterns], while the other side had a reddish-orange tint." The review by Cruce in WR mentions no such anomaly.

However, Morrison also says that he was reviewing was a preproduction model, and that Sony claims the color accuracy will improve in units shipped to stores.

Morrison also found the improvement in picture detail with the KDS-R60XBR1's 1920 x 1080 resolution, compared with a 720p display, no better than "subtle but noticeable." You would expect a bigger jump in apparent resolution, since 1080p more than doubles the number of pixels of 720p. But, though this set has a 1080p display, it can't input a 1080p signal!

That's right — the best signal it can take in is 1080i. Now, I am given to understand that 1080i fare is intentionally filtered to remove about 30% of its vertical resolution, because any "i"-for-interlaced scan will produce an artifact called "line twitter." When a video detail is small enough to occupy just one scan line, every second video "field" will omit it. The detail will accordingly blink on and off! Vertical filtering obviates that, making sure that no detail is so small as to completely disappear every 1/30 second.

So I'll bet Morrison was watching vertically filtered 1080i material (from a D-VHS tape player) scaled to 1080p by the KDS-R60XBR1. That's really not a good way to judge the ultimate picture quality of a 1080p-native display.

But Morrison had little choice, since (a) as yet there exists no 1080p consumer-video source hardware, other than a high-def PC hookup; (b) there is little if any 1080p source material, a situation that will probably change when high-definition DVDs arrive; and (c) the KDS-R60XBR1 can't accept a 1080p input signal anyway. Both reviews mention Sony's reason for omitting the capability: the present lack of an industry standard for copy protecting 1080p input.

I mention this because I think it a good idea for potential buyers of the KDS-R60XBR1 to wait until there is a successor model that does accept 1080p.

The KDS-R60XBR1 has stunning black levels and snappy contrast renditions, both reviewers say. Most HDTVs other than direct-view CRTs have problems rendering deep blacks, and CRTs are usually limited in how bright they can get. The KDS-R60XBR1 can do blacks nearly as well as a CRT (0.006 or 0.007 foot-Lamberts, per HT) and dazzle you with its brightness (93.31 ft-L). That gives a whopping full-on/full-off contrast ratio of fully 13,330:1.

"The best plasma we've measured had a black level of 0.023 ft-L; the best RPTV ... 0.080 ft-L," writes Morrison. "Most of the front projectors we've measured have a higher black level than this 60-inch RPTV. Suffice it to say, I was impressed." Clearly, the Sony SXRD RPTV "out-blacks" any existing DLP RPTV.

Part of the reason for these outstanding numbers is the KDS-R60XBR1's Advanced Iris, which automatically contracts, reducing the amount of light reaching the screen for dark scenes, and then opens up for bright scenes. Morrison says you can just barely detect it working, and if it bothers you you can defeat it by selecting one of six presnt iris levels manually. Even the full-open setting produced an impressive 3,100:1 contrast ratio.

The two reviews seem to disagree about how well the KDS-R60XBR1 does video processing such as deinterlacing and resolution scaling, with the WR reviewer being wholly thumbs-up about it and the HT reviewer noting some flaws. I have no idea why there was a difference in this department.

But on the whole, it seems clear that the initial Sony KDS-RnnXBR1 SXRDs come right out of the starting gate as the RPTVs to compare all others to ... and that's saying quite a lot.


After I wrote the above the Nov. 2005 Sound & Vision arrived, with a review of the Sony 50" SXRD model, the $4,000 KDS-R50XBR1. Al Griffin's opinion was much like those of Bill Cruce and Geoffrey Morrison: "gorgeous picture ... natural color ... deep, CRT-like blacks ... fine resolution."

Griffin also complemented "extensive feature set and picture tweaks, which go well beyond many other televisions." As the lab results and discussion online here mention, "Only minor tweaks using the red, green, and blue gain and bias controls in the set’s Advanced Video menu were needed to get [color temperature] perfect — no service-menu adjustments needed."

Color temperature is supposed to be the same value, 6500K, at all brightness levels. Most TVs don't give you that desired degree of uniformity, giving the picture a blue or red cast instead. Sometimes, there is a different false tint at different brightness levels. Such false tints are most apparent in a black-and-white picture, but also affect color pictures.

The fact that the Sony puts red, green, and blue gain and bias controls in a user-accessible menu is also unusual. RGB gain and bias are the main controls used by a professional calibrator to calibrate color temperature and grayscale. (The latter includes avoiding any green tint, not just red or blue, at the various levels of brightness.)

So the Sony SXRDs let you calibrate them on your own!

The S&V review, like the other two, noted that the Sony doesn't support 1080p HDTV input signals, even though the screen output is always 1080p. The only other minus factor the reviewer cited was the lack of a signal-strength meter to help you tune in over-the-air digital channels. Even so, the Sony pulled in all the reviewer's local stations, including the most troublesome one, without any fuss.

Oh, and the review also chides Sony's remote for not having a backlit keypad. When that's the extent of the negatives, while the positives are so prepossessing, the TV is clearly a big winner.

Sunday, October 16, 2005

Eye on HDTV, October '05

It's been a while since I posted to this blog — since July, in fact. Recently I've been enjoying the baseball playoffs in HDTV and wondering what it might take to get more homes HD-capable, sooner, so fewer of us will miss the fun!

The first big thing is to get prices down, obviously ... and that's been happening. About a year and a half ago I paid $3700 for the 32" Hitachi plasma I'm watching baseball on in my basement rec room. Today you can't buy a plasma that small — the smallest is 37" and most are 42" and 50". The small flat panels are all LCDs now. In this weekend's Circuit City flyer, there's a 32" Panasonic LCD listed for $1900, "before $190 savings."

Almost two years ago I paid $4900 for the 61" Samsung DLP rear-projection TV that I have in my living room. In the same weekend flyer, a Panasonic 61" LCD rear-projection TV lists for $3000, "before $300 savings." Or, go to the Circuit City website to find a Samsung 61" DLP rear projector for $3325 after $175 savings.

So prices have come down up to 50%, if you're willing to switch technologies, or up to 33% if you're not. Y-e-e-ss-sss!

The second needed thing is to do something about all the many sources of confusion which make potential HDTV buyers leery. That hasn't really happened yet. If anything, the marketplace is more confusing now than it was in 2004.

In the Circuit City flyer we find plasma and LCD flat panels; CRT, DLP, and LCD rear projectors; and even a direct-view CRT set with a traditional picture tube ... and those are just the HDTVs. We also find a slew of just regular TVs of the type we've had for years and years ... now on the way out, of course. When you can buy a Sony 26" HD-ready LCD flat panel for $1350 after savings, do you really want to buy a near-obsolete SDTV?

Remember, you'll need something like a 32" SDTV to be able to view a widescreen picture at the same overall size. Circuit City presently sells a Sony 32" SDTV for $550. The Sony 26" HD-ready LCD flat panel is double that in cost, admittedly ... but it is HDTV. And you can watch widescreen fare on it without annoying black bars appearing above and below the image.

Still and all, such considerations are confusing. In a few years, there will only be widescreen TVs, and virtually all of them will be HDTVs.

Not literally all, you may ask? Why won't all TVs in (say) 2009 be HDTVs?

Well, they may be ... but there is something in between SDTV and HDTV today, and it may well persist into tomorrow. It's EDTV, for extended-definition television.

EDTVs have, usually, just 480 lines of resolution: 480 rows of pixels, stacked up and down on the screen, each row containing ... well, uh, containing some even larger number of pixels; it depends. HDTVs have at least 720 lines or rows of pixels, and that number can go as high as 1,080 lines/pixel rows.

Any TV that has fewer than 720 lines is either SDTV or EDTV. As I say, usually the exact number of lines is precisely 480. The TV is SDTV if it shows the odd-numbered lines first, then the even-numbered lines a fraction of a second later. That's called interlaced scan. If all the lines are shown together each time the screen is refreshed, it's progressive scan. Progressive scan gives a more solid image with no visible scan lines. And there is twice as much detail presented over time; thus, the designation "extended definition."

You can buy a Magnavox 42" widescreen plasma EDTV this week at Circuit City for $1700. Compare that to a Philips 42" progressive-scan widescreen plasma HDTV for $2250 after savings, or a Samsung 42" progressive-scan widescreen plasma HDTV for $2700 after savings.

Yes, it's decidedly confusing ... way too confusing.

Another source of confusion is the distinction between "HD-ready" sets and "HD built-in" sets. The former don't have an internal "ATSC tuner," while the latter do.

The ATSC tuner pulls in digital over-the-air (OTA) signals, using an antenna. (Remember those?) All OTA HDTV broadcasts are digital. So are some OTA SDTV broadcasts, on the same channels — that is, some shows on these channels are HD, some SD.

Someday in the next few years, though, all OTA broadcasts will go digital. Right now, most OTA SDTV broadcasts are analog, expecting a different kind of tuner: NTSC.

The question is, do you need a built-in ATSC, or digital, tuner right now? You don't if you get all your digital channels — HD and otherwise — from cable or satellite. You do if you want OTA reception via antenna.

What if you buy an HDTV that lacks an ATSC tuner — an "HD-ready" monitor — and later regret it? You can buy a standalone "set-top box" with an ATSC tuner and hook it to your monitor at that time. Or you can get cable or satellite.

But, yes, it's another source of confusion. That's why Uncle Sam is mandating that all HDTVs built from now on be built with internal ATSC tuners. We're on the cusp of that mandate taking effect. Meanwhile, Circuit City is still offering several "HD-ready" models that presumably represent bargains — even if they're "last year's models" — since internal ATSC tuners are by no means cheap.

Another mandate of the Feds is putting the ability to receive "digital cable" right in every HDTV built from now on.

"Digital cable" involves a slew of cable channels that are being transmitted over the cable-TV wire in bits and bytes. They're typically the channels numbered 100 and above, and they include all the HD channels. Instead of renting an external cable box to pick up these channels, you can pick them up directly with a TV that (the advertising says) has "CableCARD."

In other words, the TV is "digital cable-ready."

Actually, a TV that is digital cable-ready provides just a slot into which a credit card-sized CableCARD may be inserted. You rent the card from your cable company in lieu of a box. With the card inserted in the slot, the TV suddenly can pick up digital cable channels.

Technically, the CableCARD is not needed if you just want to pick up non-scrambled digital cable channels. For example, your cable company possibly will choose not to scramble your local stations' over-the-air digital signals when transmitting them to you, allowing you to avoid the need for a CableCARD on those channels. Unfortunately, I have yet to encounter any reports of this theoretical possiblity actually working, in real life.

The CableCARD costs fewer dollars per month than a digital cable box. But the box can do more. It provides an interactive program guide to make it easier for you to find and access (or set reminders for) scheduled programs up to several days in advance. It allows you to order video-on-demand and pay-per-view programming with your remote, rather than by telephone.

Also, you can often option up the external box to one containing a digital video recorder — for more bucks per month and a lot more viewing flexibility. I find my DVR-equipped HD boxes (I have two) a godsend.

Many cable companies are gradually, over the next few years, switching to all digital channels. Then all their customers will need either a box or CableCARD. Soon, a new generation of CableCARD will let it do everything a box can do ... but the new card won't work in current slots. If you're set on CableCARD, hate the box, but want all the features, this might be a reason for you to postpone buying an HDTV.

More confusion, no?

Another thing you need to consider is whether the HDTV you're eyeing offers a HDMI (or DVI) high-definition digital interface.

It's a plug-in in the back which allows you to connect a cable box or DVD player that has an equivalent plug-in. The signal travels over the wire digitally as bits and bytes, which means it can be displayed cleaner and crisper than if it traveled as an analog signal.

DVI is good, HDMI is better. The latter incorporates digital audio signals and some other goodies that DVI doesn't support. But DVI is good enough, and if you have a cable box with a DVI output and a TV with an HDMI input, the one can be converted to the other by means of an adapter cable.

If your HDTV has neither DVI nor HDMI — I'm totally ignoring yet another digital option, Firewire — then the only way to route a high-definition signal to it from external gear is via the three-headed monster called "component video" — if it's "wideband," that is, and has enough "bandwidth" to carry a full HD signal in analog form.

True, wideband component video can give you a perfectly respectable HD picture. The all-digital HDMI or DVI picture can beat it only marginally. You don't absolutely need HDMI/DVI.

Now, that is. Rumor has it that the high-def DVD players slated to hit the market next year may not output HD at full resolution over wideband component video. Why not? An analog component-video connection can't be copy-protected. HDMI/DVI is typically copy-protected. Hollywood studios don't want you to make unlimited copies of movies in high-def.

So it is not, in my humble opinion, a good idea to buy an HDTV that lacks HDMI/DVI entirely. (Both of mine have DVI.) In fact, it won't be long before most buyers start insisting on two or more HDMI (or DVI) inputs, one for a cable or satellite box, one for a DVD player, and so forth.

And things just get more confusing, right?

Sorry about that. Because watching TV in high-definition is really great. Baseball is much more interesting, with a clean, wide, sharp, colorful picture, augmented with room-filling digital sound to give you the crack of the bat and the roar of the crowd.

And when you can record the game in glorious high-definition and then watch it when you want to, so much the better. With a HD cable box with built-in DVR, you can zap the commercials, hit pause, play with your cats, take a nap ... and miss nothing.

It's definitely habit-forming ... you've been warned!