[mythtv-users] Preparing for HDTV in 2005

Michael T. Dean mtdean at thirdcontact.com
Tue Aug 17 19:07:41 EDT 2004

Brandon Beattie wrote:

>I'm not sure the status on the following, but I know the MPAA was trying
>to get a mandate passed that required all HD equipment to auto-check for
>connections to blacklisted equipment and if connected to one it is to
>shut down output.  This is unfair, but the MPAA can buy that monopoly.  
They basically have it.  First some background, then the reason they 
have it.  (Oh, and the obligatory, IANAL, but as I understand it...)

Because it's so difficult for the government to make changes to 
regulations, the FCC included an addendum to the broadcast flag regs 
with a table (Table A) of authorized technological protection measures.  
In theory, they will be able to make changes to Table A much more easily 
than changing the regulations themselves.

Currently, there exist four technologies that are expected to be 
included in Table A when the broadcast flag ruling goes into effect on 
July 1, 2005.  These technologies include DTCP (Digital Transmission 
Content Protection) for secure transmission of compressed content over 
electrical connections (i.e. between components or even computers); HDCP 
(High-bandwidth Digital Content Protection) for secure transmission of 
uncompressed protected content over an electrical
connection used for displays (i.e. DVI-D); CPRM (Copy Protection for 
Recordable Media) for secure storage of compressed content (i.e. writing 
an authorized copy of a program onto a hard drive or DVD); and D-VHS for 
secure storage of uncompressed protected content (i.e.
writing an authorized copy of a program onto a hard drive or tape).  
These four technologies are often called "the 5C technologies" after the 
5 corporations that created them, Hitachi, Intel, Matsushita, Sony, and 
Toshiba (note, there's a lot of non-Hollywood in the 5C).  The DTLA 
(Digital Transmission Licensing Adminstrator - http://www.dtcp.com/ ) is 
responsible for licensing the technologies and ensuring appropriate 
usage (basically, making sure that companies do not add back-doors or 
other security holes/weaknesses to the system).

So, what does all this mean?  Well, the 5C technologies only perceive a 
system to be secure if every component of that system is 5C-compliant.  
If a system is perceived to be insecure, the 5C-compliant devices on 
that system must down-sample the digital content to no greater than 480p 

Since revocation of a technological measure from Table A requires 
proving it to be less effective at protecting content than other Table A 
technologies, it can be assumed that technologies that are less 
effective at protecting content than the initial Table A 
technologies--the 5C technologies--will not be added to Table A.  
Therefore, all Table A technologies--on July 1, 2005 and beyond--will 
almost definitely perceive any system containing components that are not 
Table-A-compliant as insecure and down-res the content.

When you couple this idea of down-res if insecure (i.e. not 
Table-A-compliant) with the ability to revoke technological measures 
from Table A, it makes it impossible for devices you legally purchase 
that use measures that are later revoked to be grandfathered in--you'll 
have to either never buy new components or buy all new components every 
time a measure is revoked.  (Which is a good thing and a bad thing--it 
means it's very unlikely for manufacturers to do away with analog 
connections.)  See my post at 
http://www.gossamer-threads.com/lists/mythtv/users/78371#78371 for more 

Therefore, we'll have to take our content--which is broadcast in a lossy 
digital format--and decode it to analog, then re-encode it in a lossy 
digital format (that has problems with compression of encoding artifacts 
introduced in the first encoding process).  However, like you said, come 
July 1, 2005 (or, possibly shortly before), I expect to see the MPAA 
doing their "A/D converters are copyright-infringement devices" dance again.


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