[mythtv-users] PVR250 or HD3000?

Joseph A. Caputo jcaputo1 at comcast.net
Mon Dec 20 21:33:26 UTC 2004


On Monday 20 December 2004 15:24, Michael J. Lynch wrote:
> Preston Crow wrote:
> >On Mon, 2004-12-20 at 14:56, Michael J. Lynch wrote:
> >>Other than cost, is there any reason to choose a PVR250 over a
> >> pchdtv hd3000 since the latter can MPEG2 encode both NTSC and
> >> ATSC?
> >
> >You need to go back and do some more research, as the HD-3000
> > doesn't MPEG encode anything.  (ATSC is broadcast as MPEG, so no
> > encoding is required by the recipient.)  Most HD-3000 users also
> > use a PVR-250 card for NTSC.
> >
> >Check the list archives.
>
> That's not what the pcHDTV website says.  It specifically states that
> the card
> MPEG2 encoding.  See the second line of paragraph 2 of the following
> link:
>
> HD-3000 at pcHDTV <http://www.pchdtv.com/hd_3000.html>
>
> The line I'm referencing is:
>
> "The card receives NTSC and ATSC Signals and converts them to
> digital streams which are transported across the PCI bus."

"Digital stream" does not necessarily mean "MPEG".  Raw video data is 
also digital, once the card has done the a->d on it.

>
> I know that ATSC is already MPEG2, does this possibly mean that
> NTSC is converted to some digital format that is something other
> than MPEG2?

Yes, raw (digital) video data.
>
> Further reading on the page suggests NTSC is, in fact, MPEG2 encoded.

I don't see that... in any case, read elsewhere in the list archives, I 
think this was discussed before... the NTSC side of the card is a frame 
grabber, similar to a bttv card.  It uses a CS28333 chip, which IIRC is 
the same as or similar to the chip used in newer models of analog frame 
grabber cards like the basic WinTV cards.  There is no mention of an 
MPEG encoder on the board.

-JAC


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