[mythtv-users] Specs

Joseph A. Caputo jcaputo1 at comcast.net
Thu Jan 8 16:55:54 EST 2004


Top-posting rearranged.

On Thursday 08 January 2004 10:31, Curtis Wood wrote:
> On Thu, 2004-01-08 at 17:58, Joseph A. Caputo wrote:
> > On Wednesday 07 January 2004 23:06, Yuri wrote:
> > > Hmm, could you please explain the difference?
> > >
> > > Encoding would be from video to digital (hdd) or the other way
> > > around?
> >
> > Both the 250 & 350 do hardware encoding (i.e., converting the input
> > TV signal to MPEG1/2 so that it takes up less disk space).
> >
> > Only the 350 does hardware decoding (converting the MPEG1/2 data
> > back to raw video for viewing on a monitor or TV).
> >
> > Only the 350 has an integrated TV-out (output of the decoded stream
> > to TV).  Other solutions require a separate TV-out method (video
> > card with integrated TV-out, external VGA scan converter, etc). 
> > However, note that the quality of the picture on the 350's TV-out
> > is reportedly far better than anything you'll get from any consumer
> > grade video card or VGA scan converter; I hear it's about on par
> > with standalone A/V equipment.
> >
> > Think:
> >
> > encode::decode as compress::uncompress
> >
> > -JAC
> >
> On the quality of the 350's tv out... How would it compare to an
> AT8500 -> connected to a 57" hitachi hdtv (widescreen) via DVI
> (720x480)? The only thing that sux about this setup is that the
> sharpness can be a big factor, and its at least 2x less sharp through
> a 250... Also since Im asking - I have a Sb Audigy (v1), but cant get
> to the AC3 pass through goodies, because I can only use the audio
> from the encoded stream - does anyone know a way around this? Would
> the 350 be anybetter?
>

Well, first off I've never actually *seen* a PVR-350; just going by 
other people's reports.  I'd imagine if you have an HDTV with DVI-in, 
then the best quality would be via DVI-out if you have it; however, 
you're still bound by the quality of your incoming signal + your codec 
parameters.  When you say it's "2x less sharp through a 250", compared 
to what?  Live television tuned through your HDTV?  Well, that would 
make sense since the 250/350 is not an HDTV tuner, so you're capturing 
at standard NTSC resolution (SVHS quality, at best).  If you have an 
HDTV set, you might want to consider a pcHDTV card, which has hardware 
compression & can receive HDTV stream over the air.  Check elsewhere 
for the availability of cards that can receive HDTV over cable; I don't 
think there are any available in the U.S.  Also, keep in mind that your 
CPU requirements will go up if you want to decode & play full 
HDTV-resolution streams (the pcHDTV will encode, but not decode AFAIK).  
The PVR-350 won't help in the decoding for that, because AFAIK it will 
only decode up to DVD-resolution (720x480 or whatever).

-JAC



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