> I probably spend a couple hours a day reading my 200+ newsgroups.  Again
> usually just skimming subjects for things that are interesting.

Damn. If I had that much stuff to look at, I'd *never* get any work 
done... Oh, wait.

>> If the bitrate of the source is higher than the available bandwidth, it
>> just won't play in realtime. It'll constantly stall to rebuffer. So
>> presumably the guys behind iPlayer (and every other Internet video
>> system) have to transcode to a low enough bitrate that it will actually
>> play in realtime. The result is obviously poor image quality.
>
> Clearly not, as shown in my photo.  In the case of Netflix, they use a
> dynamically adjusting algorithm so it can display lower quality if the
> bandwidth is throttled.

So they actually offer multiple quality levels? Well, I guess that makes 
good sense. I'm not sure how you'd automatically detect which one to 
use, but I guess with the right client software it ought to be possible.

>> Yes, the picture looks fine. I still don't understand how that can be
>> possible though. The Internet isn't fast enough. I don't see how you can
>> get the data from A to B fast enough for realtime playback.
>
> Compression.  We've been over this before.

Lossy compression allows you to make the file size be anything you want 
it to be. But this does not happen by magic; it happens by degrading the 
picture quality. So while it obviously /is/ possible to reduce a video 
stream to, say, 3KB per second, it wouldn't be worth watching. What I 
can't figure out is how they can shrink it down to realtime download 
speeds without it looking awful.

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