[mythtv-users] DVICO FusionHDTV III QAM card

[Cory Papenfuss]

> My understanding is that the pcHDTV and the FusionHDTV III are both 
> "software" HD tuner cards--they have no MPEG decoder hardware on board. 
> Instead, they pass demodulated signal data through the bus to a software 
> decoder.
 	They are basically RF frontends and 8VSB/QAM hardware demod boards... 
basically just a modem.  Whatever bits come in over the air are spewed out the 
PCI bus.

>
> I think what Michael is saying is that if the channel were, in fact, 
> encrypted, the signal received over the bus would not be an MPEG stream, so 
> when it's passed to a software MPEG decoder, the decoder would not be able to 
> decode the video.  In other words, he's agreeing with your initial guess of 
> how to tell it's encrypted.
>
> Mike

 	I'm not sure which part of the video is encrypted, but I would suspect 
it's at the PS (Program stream)  level.  Remember that an MPEG-TS (Transport 
stream) can contain lots of different PS's and at the same time.  I'm sure that 
they could encrypt on a per-PS basis so the framing of the bits coming down in 
the TS would be readable.  If you tried to decode the content of a PS, however, 
it would be like issuing 'mplayer /dev/urandom'

-Cory