[ILUG] SDMI initiative

[Niall O Broin]

On Thu, Sep 28, 2000 at 01:01:46AM +0100, Fergal Daly wrote:

> Not quite, a ripped CD track hasn't been compressed already. It wouldn't 
> make a difference if the compression was lossless, but each time you 
> uncompress and recompress you get further away from the original and could 
> get artifacts coming through.

Good point - though as Colm pointed out it's a different kind of
compression, using psycho-acoustic models. However, JPEG uses a similar kind
of compression (psycho-visual model ?), discarding information that the eye
doesn't take much account of, but you will surely see the effects of
repeated compression/decompression with JPEG.


> It's the same as when you make a copy of a  copy of ... with VHS tapes.

Not quite as bad - not so many analog steps involved.

> hassle for the mp3 algorithm. There's something called Macrovision which 
> does this for video signals, it makes them virtually untapable, even though 

Macrovision is about as secure as a plastic padlock - I imagine SDMI will be
a little tighter.



Regards,


Niall