Was a mistake made in the design of AACS?

Steve Schear s.schear at comcast.net
Sat May 5 12:06:48 EDT 2007


At 07:50 AM 5/4/2007, Nicolas Williams wrote:
>On Thu, May 03, 2007 at 10:25:34AM -0700, Steve Schear wrote:
> > At 03:52 PM 5/2/2007, Ian G wrote:
> > >This seems to assume that when a crack is announced, all revenue
> > >stops.  This would appear to be false.  When cracks are announced in such
> > >systems, normally revenues aren't strongly effected.  C.f. DVDs.
> >
> > Agreed.  But there is an incremental effect.  In the same way many people
> > now copy DVDs they have rented many will gain access to HD content made
>
>Wait, are you saying that people copy rented DVDs onto DVD media?  Or
>that they _extract_ the content?
>
>There's a big difference: there's no need to crack the DVD DRM system to
>do the former, but there is for the latter.

I guess I wasn't clear.  Unlike ripping and copying DVD's bit-for-bit, 
content ripped from H-DVDs and BluRay discs are first distributed as simply 
unencrypted copies.  Watching this content means you will probably do so 
from your PC (e.g., using a curent version of Power DVD) as burning a 
bit-for-bit HD DVD/BluRay is either not available or economically 
practical.  Later, HD videophiles re-encode the content using the same 
advanced coders (i.e., H./X/264 andVC1) so at least the feature movie can 
be stored on a dual layer DVD.  Despite the smaller data size of the DVD 
(about 8.5 GB) vs. HD media (20+ GB) the quality of playback is impressive, 
good enough for all but the most discerning Home Theater buff.

>Well, there's an idea: use different physical media formats for
>entertainment and non-entertainment content (meaning, content created by
>MPAA members vs. not) and don't sell writable media nor devices capable
>of writing it for the former, not to the public, keeping very tight
>controls on the specs and supplies.

Authoring DVDs are available for people wishing to master protected 
content.  These, unlike the consumer variety, allows the CSS to be 
present.  Special burners, never very popular with consumers, even video 
philes, are required.

Steve 

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