[mythtv-users] Pinnacle PCTV HD Pro Stick
jedi at mishnet.org
Thu May 22 15:18:57 UTC 2008
On Thu, May 22, 2008 at 09:57:50AM -0400, Carl L. Gilbert wrote:
> On Thu, 2008-05-22 at 14:45 +0100, Mike Perkins wrote:
> > Carl L. Gilbert wrote:
> > >
> > > What is the difference between an HDTV card and a digital SDTV? If they
> > > are both simply dumping MPEG streams, then I don't see the difference.
> > > And I am at a loss as to why there is a special section about HDTV cards
> > > and why all digital tuner cards don't claim HDTV?
> > >
> > Digital != High Definition. Digital is just a different transmission technique
> > compared to analog. SD = Standard Definition, HD = High Definition. Analog can
> > only (for practical purposes) carry SD. Digital can carry both SD and HD.
> > Although there are similar 'streams' within the Digital transmission which carry
> > SD and HD, HD may be encoded differently than SD. HD has much larger amounts of
> > data and requires much more processor power and uses much more storage (so
> > faster data busses may be required).
> Right, thats why I compared an HD card to a "digital" SD card. IN this
> case both cards are digital. And what I have read indicates digital
> streams are not processes but stored as is. So I don't see what special
> an HD card is doing that a digital SD card isin't? Both streams go to
ANY digital capture solution is going to be simpler because it doesn't
have to digitize anything. I am not sure there is such a thing as a
"digital SD card" (DVB excepted). SD capture cards aren't just capturing
the incoming video, they are also digitizing it since the stream is coming
in as analog.
In the US this would even be the case for "digital SD". It's going to hit
your system as an analog stream and get re-digitized.
> the drive unprocessed. Is it that the HD is more dififcult to pull out
> of the transport stream than the SD digital signals? Just trying to get
> what makes an HD digital capture card different from an SD digital
> capture card. They don't even need to do encoding right!?
An HD capture card doesn't have to do much work really. The data is
already in a format suitable for computer consumption.
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