[mythtv-users] pcHDTV with PVR-350 for output

jack jr at jrh.net
Sat Oct 23 05:48:37 UTC 2004

While mythtv is fairly general it does actually store encoder specific cards
like the pvrXXX series and the pchdtv cards in their native format. Ie, the
*.nuv files are actually just mpg or ts files respectively with a nuv
suffix. There is no way the PVR350 is going to play a pchdtv atsc stream.

On the other hand there is EVERY reason to want to do what you are asking, I
really can't understand Jarod (who otherwise is an absolute font of good
information) saying there isn't.  An atsc stream of even standard definition
programming is going to usually blow away the ntsc equivalent, no matter the
source, including cable, over the air, and satellite. So while you are not
going to be able to use the pvr350 for your output, getting it working is
not a bad idea by any means. You will need a fairly beefy machine to either
resize in real time or transcode ahead of time. 

> -----Original Message-----
> From: mythtv-users-bounces at mythtv.org [mailto:mythtv-users-
> bounces at mythtv.org] On Behalf Of Dan Lanciani
> Sent: Friday, October 22, 2004 10:32 PM
> To: mythtv-users at mythtv.org
> Subject: Re: [mythtv-users] pcHDTV with PVR-350 for output
> Jarod Wilson <jcw at wilsonet.com> wrote:
> |On Friday 22 October 2004 21:56, Dan Lanciani wrote:
> |> I've been trying to send ATSC programming from a pcHDTV card through
> the
> |> MPEG decoder in a PVR-350 using MythTV 0.16.  It seemed that the
> |> configuration setting to use the PVR-350's output was just being
> ignored.=
> |=20
> |> (I could run an X server on the 350 and then of course everything
> display=
> |ed
> |> on the TV, but through the dumb framebuffer interface.)  There were no
> |> error messages or anything else to indicate that the PVR-350 was being
> |> accessed at all.
> |>
> |> Finally I had the thought to try using the PVR-350's own analog tuner
> as a
> |> source rather than the pcHDTV.  The PVR-350's output then came to life,
> |> turned on and off by the configuration option in Playback Settings just
> as
> |> it should be.  Is something in MythTV deciding that the PVR-350's MPEG
> |> decoder can't handle the ATSC stream?  Or is there some interdependence
> |> between PVR-350 capture and output (which would seem to defeat the
> purpose
> |> of MythTV's distributed architecture)?
> |=46irst off, the 350's decoder is set up for NTSC or PAL sized mpeg2
> frames=
> |, not=20
> |ATSC sized frames. I don't think the hardware is physically capable of=20
> |handling something that big.
> So does something in the MythTV code know this and simply refuse to try?
> Is
> this documented anywhere?
> |Second, why on earth would you want to output=
> |=20
> |HDTV content through an SVideo connection that is 720x480, interlaced?
> Because I don't care about "H"DTV.  I just want ATSC reception converted
> to NTSC.
> |You'=
> |d=20
> |effectively be down-sampling the ATSC signal back down to NTSC,
> Yes, that's exactly what I want.
> |so why even=
> |=20
> |bother?
> Because analog will eventually go away and even now ATSC offers me a
> picture
> with less ghosting and interference.
> |For HDTV, you really need to be outputting to your TV via VGA, DVI =
> |or=20
> |component for it to be worthwhile.
> Well, clearly this is a matter of opinion (as suggested by the existence
> of
> set top boxes that receive ATSC and downconvert to NTSC as necessary).  My
> TVs
> do not have VGA, DVI, or component inputs.
> It's possible that I misunderstood the generality of the MythTV model.  I
> thought that the pcHDTV card was just another source of input and the PVR-
> 350
> just another output device.
> |This has all been discussed before, plea=
> |se=20
> |search the archives if you want more insight.
> I've searched extensively and I found nothing to answer my question.
> Could
> you point me to the specific discussion of PVR-350 output used with the
> pcHDTV as source?
> 				Dan Lanciani
> 				ddl at danlan.*com

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