[mythtv-users] SiliconDust to Announce CableCard ProductatCES[RUMOR]

Tortise tortise at paradise.net.nz
Fri Jan 8 06:58:06 UTC 2010


----- Original Message ----- 
From: "Robert McNamara" <robert.mcnamara at gmail.com>
To: "Discussion about mythtv" <mythtv-users at mythtv.org>
Sent: Friday, January 08, 2010 2:58 PM
Subject: Re: [mythtv-users] SiliconDust to Announce CableCard ProductatCES[RUMOR]



>
>> Whoah, easy there. The ICT is not a part of HDCP, it's part of the
>
> Blu-ray/HD-DVD AACS specification. Unless you have a licensed AACS
> decrypter (none exists in linux, note the specific use of the word
> *licensed*) and ACCS-encrypted content (read: not cable) you will
> never see any resizing of your video.
>
>> So no, that's not not going to happen.
>
> Robert
> _______________________________________________
>
> I like your confidence Robert.
> Can you be sure there will be no AACS content distributed over cable? (Or
> DVB-x ?)
>
> What would happen when the broadcaster's content source is Bluray or HD-DVD
> - with ICT embedded?

>This really seems to be FUD-- why conjecture about something that has
no basis in fact?


Much content I see broadcast is available in the shops on disc.  Some discs have ICT.  HDCP recognises the "analogue hole" by 
cutting HD down to SD in an effort to minimise the risk of generation of non protected digital HD copies.  VDPAU NVIDIA cards are 
HDCP compliant.  These facts suggest to me there is risk potential for reduced display definition from HD content when using 
component HD Displays.

References:
http://en.wikipedia.org/wiki/Hdcp
http://en.wikipedia.org/wiki/Image_Constraint_Token
http://en.wikipedia.org/wiki/Advanced_Access_Content_System
http://en.wikipedia.org/wiki/Analog_hole
http://www.aacsla.com/press/


>Yes, we all know that content providers would like
to limit our access to material and control the manner in which we
experience it-- but why just plain make up scenarios

I have seen nothing to say the ICTokens can not be transmitted, quite the contrary.  However thinking about this some more I 
understand the digital chain is a two way thing, so without a return path I cannot (now) see how a transmitter could know to scale 
down transmission definition to selected clients.

>and try to drum up strong reactions to them?

I think that's somewhat over-extrapolating my questions - that merely seek to understand the reality of the situation.

>There is nothing whatsoever that would lead one to believe that an ICT-like mechanism will be applied to cable content.  Nothing.
>We could sit here all day and make up scenarios in when the content providers could irritate us, but you're putting together two 
>and two and getting "magenta" here.  It is not
possible to send AACS content (and thus, not possible to "embed" the
ICT) via current US cable systems.  They'd have to build a new cable
system around that as the control mechanism.  Once again, anything
they broadcast via the current cable system is incapable of carrying
the Image Constraint Token.  So "embedding" it in current cable
content is not possible.  If the broadcaster were using bluray as
their content source, it would *still* need to be decrypted,
modulated, and re-encrypted with the DigiCipher II encryption variant
used by nearly every single US cable company.  Could they change their
encrypting/rewrite their standards?  Sure.

I am not particularly familiar with the standards for the US cable systems you refer to however your explanations will be 
appreciated.

>But there is *nothing*
whatsoever that leads one to believe that they will, and what you are
proposing is not just technically unfeasible in the current system,
it's downright impossible.

>So yeah, let's take a breath and not alarm people.

Robert
_______________________________________________

My intention is not to alarm people, it is to understand the reality of the situation that we have all heavily invested in kit and 
time.  If people become alarmed that is more for them to make that call if reality justifies that however based on the above it 
seems there would be little cause for alarm - if anyone was contemplating whether to be alarmed?

Despite the questions about alarm I do appreciate your prompt responses Robert and with your help it seems there is no looming cause 
for concern about analogue cut down.

What does the HDCP compliance embedded in vdpau NVIDIA video cards actually do?  Anything? 



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