On 4/26/2010 3:19 AM, Invisible wrote:
> I mean, if you're going to force everybody to buy a new TV, new
> receiver, new type of disk and a new machine to play it, why it increase
> the resolution *significantly*? Why only increase it by a small amount?
> I don't understand that.

Partly bandwidth related. The UHF/VHF frequency space has only a certain 
amount of bandwidth per channel. Now, while a HD broadcast in 1080p at 
an "acceptable" compression ratio might fit nicely within the allotted 
bandwidth for a channel, doubling the horizontal and vertical 
resolution, for example quadruples the number of pixels on the screen. 
Eventually, the video would need to be compressed to the point where the 
image would be nothing more than a macroblock-fest.

> (And hell, half the equipment and content that says "HD" on it isn't
> even full resolution anyway... Why allow half a dozen resolutions when
> it would have been far simpler for the designers and less misleading for
> the public if they allow only one resolution?)

We're in a transitional period right now. Give it time. What really irks 
me is the way the cable company has been handling content. They have 
allotted no fewer than 4 channels per local station, which is, IMO 
completely unnecessary, and (if the channels aren't just aliases, and 
some aren't: they're analog variants!) it's a horrible waste of 
bandwidth. I can understand simulcasting the analog variant for those 
who do not have HD equipment, but do not want to rent a box.

> Hell, when I was at uni ten years ago we had computers exceeding these
> resolutions. With Windows NT 4.0, Service Pack 4. Has technology not
> moved on since then? It's not like there's any technical challenge to
> using a higher resolution, after all...

In both the digital flat panel and the CRT's case there is some 
technical challenge to higher resolutions: Eventually the frequencies 
involved get so high that capacitance becomes VERY important, and 
circuit design becomes exceptionally tricky, to the point where traces 
at certain distances from each other (whether on the same layer, or 
overlapped in different layers of the board) will essentially act as a 
low-pass filter killing the signal.

> PS. I am similarly baffled by the current fashion for "widescreen" TVs.
> Given that 99.998% of all video content ever created is in 4:3 aspect,
> what the hell is the advantage of buying a TV with a 16:9 aspect?? I
> don't understand.

Movies.

Going back to why movies went widescreen (they used to be displayed at a 
square ratio, even!) has to do with how the human visual field works, we 
have a wider angle of view on the horizontal axis than we do on the 
vertical.

-- 
~Mike

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