Orchid XP v8 wrote:
> 
> OK, try this:
> 
> http://download.orphi.me.uk/Video/Example.mpg

Ok, it's not horrible, I have to admit. It's hard to see the artifacts 
'cause the movement is so fast and due to fact that interest of viewer 
is drawn to the dancing movement in the middle of the picture (the point 
of MPEG and JPEG).

> 100% flawless picture quality with absolutely no visible artifacts of 
> any kind - and with a highly intricate and detailed image full of 
> motion. And it's only 4 MB. [Admittedly it's also only a few seconds...]

On this I can't agree. There are visible artifacts on gradients. I tried 
to shoot some examples on it, but my digicam jpg-messed the fotos even 
more (the other one is cropped in Gimp, hence png to avoid more messing up):
http://www.zbxt.net/~aero/AndVid1.png
http://www.zbxt.net/~aero/AndVid2.jpg

On those images the clip has been decoded with hardware decoder (em8300) 
and softened while moved via Y/C -signaling. And JPEG'ed after that by 
my digicam, so don't assume to find all the same artifacts right away. 
But I noticed them also (actually, at first) on my laptop, with software 
decoding (and a goddamn TN-panel), without pausing the clip oslt, so 
they do exist. Easiest way to start finding them is pausing the image 
(eg on 0.4 sec is a good place) and check the gradients of the noise at 
the background.

OTOH, don't try to learn to notice such things automatically. It's a lot 
easier to enjoy the show itself, when you're not scanning backgrounds 
etc for artifacts...

-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid

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