INTRODUCTION
Many technology trends that promise a "revolutionary" change in the way we live our lives or the manner in which we enjoy our favorite activities rarely live up to the hype with which they are announced. In the case of high-definition television (HDTV), however, the impact could not be more real. Looking at a high quality program on a large new high definition display is one of the most stunning experiences that consumers have been able to enjoy for quite some time. It really is that much better.
It's no surprise, then, that HDTV set sales are exploding, particularly as more channels in high definition (HD) format are being made available and as set prices decline. Today's new HDTVs offer not just the promise, but also now the reality of tremendously improved image quality. The clarity, color and vibrancy of the image are stunning, regardless of whether you're enjoying a ball game, your favorite drama or a nature documentary. In fact, it's so good, it's hard to go back to viewing regular, or standard definition, TV programs as the image quality seems so much worse in comparison.
The core reason why HDTV looks so good is that the programs and the TVs designed to display them have more resolution than the TVs we've all grown up with. Resolution may sound like a hard concept, but it simply means showing more detail in an image. Just as digital cameras with higher megapixel ratings capture more detail by breaking up an image into finer and finer dots than cameras with lower resolutions, so too does HDTV improve the image quality vs. traditional TVs. HDTVs have the capability to show more smaller elements than regular TVs, much like higher resolution printers (say, 1,200 dpi) can print with more detail than those with lower resolution (such as 300 dpi).
But the HDTV experience is not just about the TVs. Everything from the cameras used to record the programs you watch, to the editing equipment used to refine them, to the broadcast equipment used to send them out (over-the-air, via a cable TV provider or via a satellite) to a TV receiver designed to show them—all of this equipment needs to be upgraded for people to enjoy the amazing quality of HDTV.
Another important point is that not all HDTV is the same. In fact, there are technically 18 different Advanced Television Standards Committee (ATSC) formats for digital broadcasting and six are considered high-definition. However, only two—known as 720p and 1080i—are really in common usage. (As a point of reference, regular standard definition TV has a resolution of 480i.) The number portion of each of those standards refers to how many vertical lines there are in a single image, while the "p" and "i" refer to how the image is created on the screen. The "p" stands for progressive and means that each individual image that appears on the screen (remember—TV is essentially a bunch of different still images that move across a screen very quickly) is created from top to bottom, much like a painter fills in a wall one stroke at a time. The "i", on the other hand, refers to interlaced, which means every other line is painted—typically odd lines first—and then the process starts over again to fill in all the even lines. Once again, think of someone painting a room, but this time imagine they're painting stripes and not switching colors until they completed all the first color stripes from ceiling to floor. On a TV this happens at a very rapid rate, however, so our eyes perceive it as a single image.
In addition to the 720p and 1080i standards, there has been talk about the 1080p resolution standard, which on paper, seems to offer the best of both worlds—the 360 additional lines of image resolution versus 720p as well as the progressively scanned screen. 1080p, some argue, is the penultimate HDTV standard, offering the highest possible screen resolution (for TV applications) as well as future-proofing a purchase for those customers who don't want to be impacted by evolving consumer electronics standards. If you have source material, or content, that's created with 1080p resolution and display it on a screen that supports 1080p, the quality is absolutely stunning, with a level of detail that is more than twelve times higher than that of traditional standard definition TV.
Despite these improvements, however, the real-world benefits of 1080p aren't quite as clear-cut as they may first appear. The main problem is that there is virtually no content that's widely available in 1080p format (other than the output from some PCs, which would require using these TVs as really big computer monitors). As a result, there is currently little that can take advantage of these advancements in screen resolution. In the case of broadcast TV, there is no standard for broadcasting signals in 1080p. High-definition DVDs have been discussed as a possible source for 1080p content, but given the format battle between the HD-DVD and Blu-ray camps (two competing standards—think VHS vs. Beta), there are now serious doubts about how soon regular DVDs (which have just 480p resolution) will be replaced. Plus, not all high definition DVD players—whenever they do appear--will even offer 1080p-capable outputs. Ironically, the only significant source of 1080p material that's expected by 2006 will be the forthcoming PS3 gaming console system from Sony.
Finally, given that much of the material most people watch on their televisions is still not even in high-definition, namely standard definition programming, DVDs, videotapes, gaming consoles, etc., it's also important to realize that a higher definition screen can actually magnify the imperfections of these common video sources. The basic issue is that any television will take whatever source material it receives and fill in the entire screen. With high definition program material on high definition screens, this often results in a direct mapping of source content detail to screen resolution capabilities.
However, with lower definition source materials, high resolution TVs need to "fill in" the missing gaps to create an image that covers the entire screen and not just a small section in the center. This process of filling in, commonly called "upconversion," involves making up image material that isn't there in the original signal. As you might surmise, this isn't an easy process and some TVs are much better at it than others. No HDTV, however, can create an image from standard definition TV material that looks as good as it can with true HD material. In fact, in many cases, a standard definition program that's viewed on an HDTV looks worse than it would on a very inexpensive standard definition TV. If everything that someone watched was in HD, this wouldn't be a problem, but the reality is, standard definition programs and sources will be a significant part of most individuals' viewing habits for many years to come.
As a result of all these concerns, consumers who are considering the purchase of a new HDTV set need to seriously consider the potential benefits of 1080p resolution and determine if the cost differences between 1080p and 720p/1080i HDTVs are justifiable. For AV enthusiasts who are willing to work through the high definition DVD format wars and are eager to enjoy the best possible image quality, 1080p TVs will certainly be worth it. Similarly, media center PC enthusiasts who want to play PC games or view high-resolution digital photos will find that 1080p displays will give them the most satisfying experience. For the general public, however, it will probably be several years before the price premium between 720p/1080i and 1080p TVs narrows enough to motivate consumers to adopt the higher resolution format.
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