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Friday, January 23, 2009

High-Def Hoopla (for the non-geeky)

Doing The 1080p

There was once a time long long ago when a person would go to a store selling TVs and the only thing they'd have to worry about would have been the size - 21 inch, 25, 29 ... and maybe whether the TV has a Picture-in-Picture option (for the haggled man of the house :-P )

That's all in the past now. These days everyone's into HD (or high-definition) televisions. The rage for LCDs and Plasma sets continues unabated. Open the news-papers around festival time and you'll catch a hundred ads proclaiming that you need to ditch your old CRT TV set get yourself a new Plasma or LCD. Sadly, its not that simple. When buying such a new set there's a thousand things that can go wrong with selection. But what I'm talking about here is the way the term "HD ready" is perceived by the common man. The mere term HD evokes thoughts of a temporary escape to a visual wonderland. Whereas HD-ready isn't quite the same as full HD.

When a TV is marketed as HD-ready in India, it most likely has a resolution of 1366x768. This is NOT a proper High-Definition resolution. They will most certainly accept HD input signals, but they will not display it optimally. What one should really go for is Full-HD. Full-HD displays are capable of showing images at 1080p resolutions.

The resolutions available in this category are 720p, 1080i, and 1080p.
720p = 1280×720 resolution = Progressive scanning
1080i = 1920 x 1080 resolution = Interlaced scanning
1080p = 1920×1080 resolution = Progressive scanning

Interlaced video has been around as long as there have been televisions with cathode ray tubes (CRTs). Analog televisions use interlaced video, and we're so used to it that it's not something that we dwell upon. High definition video can be either interlaced or progressively scanned.
Progressive scan means the lines that make up the TV picture are displayed all at once in sequence. Interlaced means the lines that make up the picture on your TV screen are drawn in an alternating fashion. For example, if 480 lines are present in a picture, then the first frame has 240 lines and when the next frame is drawn, the other 240 lines are shown. The problem with interlacing technology is this alternating line drawing tends to cause the eyes to see a flicker. Once again, HD formats need a proper input from DVD and BluRay players. In general, HMDI is the connection of choice, though component cables can transfer HD resolutions too.

A high-definition display is however of no use without a proper source. High-definition image sources include terrestrial broadcast, direct broadcast satellite, digital cable, high definition discs, internet downloads and the latest generation of video game consoles. The Sony Playstation 3 and the Xbox 360 are both game consoles capable of outputting HD content. The PS3 even has a built-in BluRay player.

High-Def is all the rage now with even the adult film industry taking note of it. Actress Jesse Jane is considering plastic surgery to take care of some imperfections. She is having her breast implants redone because they currently look odd in high definition. “I’m having my breasts redone because of HD,” she said. Note: I don't know anything about the adult film industry. I'm just saying this cos I read it somewhere. :D

Oh, speaking about BluRay Discs, they are a type of optical storage medium of the same size as a DVD. A DVD uses a red (650nm wavelength laser) and can store either 4.7gb or 8.5gb (dual layer DVDs). However, BluRays bring a whole new game - they can store upto 50gb on a dual layer BluRay disc. This is thanks to the blue laser used, having a shorter wavelength of 405 nano metre. There used to be some mild competition from a rival format called HD-DVD but those are all but extinct now, thanks to Toshiba withdrawing its support for HD-DVDs.

In India, we don't have any broadcaster using HD signals for regular television channels yet. Though most of the direct-to-home service providers are making the right noises. Besides, the Indian government has taken the decision to broadcast the 2010 commonwealth games ONLY USING HDTV TECHNOLOGY. So no commonwealth for the analog crowd.....

Not to mention, the USA has given its broadcasters a deadline of February 19th to switch over to digital signals. Why should you be concerned you ask? Simple, if you live in the US, starting 12 a.m. local time on Sunday, February 17, 2009, the only show to watch using your analog TV will be reruns of static :D . There is hope however that President Obama could possibly delay the transition.

I bet the digerati are jumping with joy!


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