[mythtv-users] HD input in the future (DVI and HDMI)

[Sean Cier]

Alex wrote:
 > Brad Templeton wrote:
 >> Sean Cier wrote:
 >>> protection: DVI+HDCP means DVI + copy protection, while HDMI basically
 >>> means DVI+HDCP+Audio+BidirectionalCommunications
 >>
>>I had read a source that suggested you could not get a licence for the
>>HDMI stuff if you didn't promise to do HDCP, but I haven't verified that.
> 
> What would be the point of doing HDMI without HDCP?

I hadn't meant to imply that HDMI without HDCP was even a possibility -- 
even if there's any chance it's technically or contractually possible, it's 
nowhere near likely to happen.

> HDMI is really
> geared towards the consumer electronics market.  I have yet to see a
> DVI/HDMI source in this market which didn't support HDCP.  All the
> current receivers support it too.

Exactly.

> Just because the transmitter and receiver support HDCP, one does not
> have to use it unless the content provided requires that level of
> protection.

Which we have to assume will be the case for all content one day, likely 
before long.  Of course, that's not a guarantee -- look at the original red 
book spec and you'll see that even CDs have a 'copy protection flag' bit, 
which is universally ignored.  But even given the chance market forces 
dictating that none of this copy protection (in particular the broadcast 
flag) is ever flipped on, we have to assume it will be.

>>They have developed whole new rafts of key revocation tech that, in theory,
>>let them revoke only the solo device that was compromised.   
> 
> Yep - that's one of the intents of HDCP.  It is quite technically
> feasible as each device has a unique value.  However as the previous
> mail alluded to, it may never be put into much practice.  Discovery
> and management of a list of compromised key sets is not trivial.

And even beyond the technical challanges are the economic issues.  E.g. 
who's going to pay for updates to devices with revoked keys, or replacing 
those devices that aren't upgradable -- the studios who don't make the 
hardware or the hardware manufacturers who don't drive the revocation 
decision in the first place?  And more significantly, what kind of consumer 
backlash are we going to see the first time several tens of thousands of 
consumers discover their TVs will suddenly no longer play the latest DVDs or 
TV?  That's not just bad for the brand's reputation, it means money spent 
for customer support.  And when it comes down to the bottom line rather than 
abstract theories and paranoid speculation, the affected companies will 
really have to take a good hard look at how much real money this technology 
is actually saving them.

-spc

-- 
  /-                 Sean Cier <scier at PostHorizon.com>                  -\
( Everyone should believe in something; I believe I'll have another pint )
  \-                 http://www.PostHorizon.com/scier                   -/