HDTV

Introduction
The purpose of this TekSpek is to define what HDTV is, how it will become pervasive in the not-too-distant future, and its relevance to you in 2006.

The background
The emergence of HDTV has coincided with the mass-market release of large-screen LCD and plasma displays, up to 50-inches across, that need better feeds to compensate for their increased size. The acronym HDTV stands for High-Definition Television, and the aim of HDTV is to increase current image quality, over and above what's referred to as SDTV (Standard-Definition TV), via higher-resolution digital broadcasts.

Current U.K. (PAL) SDTV is broadcast/displayed with a maximum of 576 visible lines with up to 720 pixels per scanline. The aspect ratio governs the total number of lines and pixels used. For example, a PAL DVD, displayed on a standard 16:9 widescreen display and featuring a native 1.77:1 aspect ratio, will be shown with a 720x576 resolution, via non-square pixels. SDTV feeds can be either analogue or digital, with the latter benefitting from a lack of ghosting that's prevalent with analogue broadcasting. The vast majority of SDTV sets continue to be CRTs, more than capable of displaying the necessary resolution, whilst newer LCD and plasma TVs are slowly encroaching on the market.

The technology
HDTV requirements, however, stipulate that a receiver must be able to display, digitally, a minimum of 720 vertical lines progressively or 1080 lines interlaced. Does that then make a regular XGA CRT computer monitor, outputting 768 vertical lines progressively, an HD-ready display in the strictest sense of the word? The answer is no, because the HD-ready tag also requires receivers to be capable of displaying a 16:9 aspect ratio, which translates into in overall pixel resolution of 1280x720. Basic HDTV resolution, then, is beyond what the vast majority of consumer CRT-based televisions can reproduce, so it becomes the domain of other displays, headlined by LCD and plasma technologies. It's worth noting that larger PC-based CRT monitors can display HDTV resolution without any problems; it's just that your living-room CRT TV cannot.

In addition to displaying either 720p or 1080i broadcasts in a 16:9 aspect ratio, true HDTVs need to have at least one digital input. The choice for consumer HDTV sets is either DVI or HDMI connectivity with inbuilt HDCP protection, and manufacturers tend to favour the all-encompassing HDMI connector on their displays. Further, whilst not officially ratified, HDTV sets tend to be able to receive and output Dolby Digital audio.

The market, trend and players
HDTV's higher resolution will allow for broadcasts carrying a greater amount of detail than what's available today, up to 4x SDTV's. Recent years have seen an influx of flat-panel displays based on plasma and LCD technology. Both offer the higher pixel count demanded by HDTV and, crucially, both technologies allow for large-screen panel production that'll showcase HDTV's better image quality.

The home market is changing to reflect the above fact. LCD panel production, in particular, is mature enough for electrical vendors to sell, for example, a 32-inch widescreen HD-ready LCD TV for around £1,000. Most ship with a native resolution of 1366x768 pixels, thereby satisfying HDTV's basic visual specification, and most also feature at least a single HDMI connector. Plasma, DLP (Digital Light Processing) projectors and a handful of recently announced CRTs are also capable of outputting HDTV feeds, so the choice of display depends upon your individual requirements and budget.

Sony, Toshiba, Panasonic, Samsung, Philips, to name but a few, all have invested heavily into high-resolution HD-capable displays. They're here to stay, with LCD-based TVs leading the way. Size-wise, 26-inch widescreen displays are considered the absolute minimum to enjoy HDTV, and most commentators recommend a 42-inch screen to fully exploit the extra detail that HDTV has to offer. Right now, in early 2006, a decent 42-inch HDTV-ready LCD or plasma TV will cost you £2000.

HDTV-Ready displays are now available from all and sundry, yet their true effectiveness, in terms of programming, will only be realised when HDTV content is rolled out by the major broadcasters and issued via high-definition DVDs. Here's where the U.K falls down in comparison to America and Japan. The BBC will begin trialling HD broadcasts in mid-2006 and expects the bulk of its programming to switch over to HDTV by 2010. Sky, too, is also gearing up for HDTV and will be begin broadcasting selected channels in 720p format in the upcoming months. Football fans, however, will rejoice at the news that the 'Auntie' will broadcast its selection of World Cup 2006 matches in glorious HD.

Until HDTV broadcasts are widespread, though, the purchase of a HD-ready display is more of a lifestyle (Xbox 360, anyone?) and future-proofing choice than of any immediate quality benefit, other than increased viewing area afforded by big-screen plasma and LCD TVs.

What the retail industry needs as an agreed-upon set of specifications that define exactly what HDTV is. Too many current displays are labelled with the HD-ready tag whilst not fulfilling the requirements discussed above, and the likes of Sony are further clouding the issue by stating that true HD requires 1080p compliance.
The future
The general acceptance of HDTV in Japan and the U.S.'s migration to high-def. broadcast and displays ensures that HDTV, both in terms of hardware and content, will become the norm in the years to come. The question consumers in the U.K. face is whether to opt for a compatible display now or wait until HDTV content has taken over from SD feeds. It's worth noting that widescreen TVs, primarily CRTS, were available significantly before 16:9 content became pervasive. What's clear, however, is that most large-screen displays, which by inference refer to LCD, plasma or DLP, now have the innate ability to display 720p HDTV in widescreen format, so it's a matter of U.K. broadcasting catching up with hardware.

Think of it this way - HDTV is a juggernaut that's not going to be stopped, and its introduction in the U.K has spelt analogue SDTV's demise. The hardware is currently available and content, in terms of broadcasts and recorded material played back by HD-DVD or Blue-ray machines, will be available soon enough. Those that jump on the HDTV bandwagon now do so in the knowledge that it's here to stay.