[pvrusb2] Jumpy Video in Mythtv

[Mike Isely]

On Wed, 27 Jun 2007, Mark Goldberg wrote:

> On 6/25/07, Mark Goldberg <marklgoldberg at gmail.com> wrote:
> > It is somewhat better but still is not smooth. Before it crashed and
> > it has not since I built from your snapshot. Is the firmware a good
> > one? (from pvrusb2_inf_24117.zip). I could not get one from the CD
> > that came with it. I can capture a few seconds of video to a .mpg file
> > and email it, if that is what you mean by a click. I can also boot to
> > XP and see how it does with the driver it came from. Then, I could try
> > to capture the firmware. Let me know what you suggest.
> > I'm not uncomfortable modifying code and rebuilding kernel modules, so
> > if there are any suggestions to help debug, i could do that too.
> >
> > Mark
> >
> 
> Someone on the myth list suggested that the pal 576 vert height error
> message might be of importance. i went into the myth setup and
> selected NTSC explicitly instead of ATSC. ATSC stuff from the HD tuner
> still works fine, and SD stuff from the pvrusb2 now seems to work
> pretty fine now also. There are three minor issues left. The audio is
> occasionally distorted on the peaks, and changing the audio level in
> the sysfs interface does not seem to help. It may be that the input is
> just too high and needs attenuation. Occasionally, the audio is
> strange sounding, with a high pitched hiss and distortion. Stopping
> the capture and reselecting seems to clear it up. Rarely, there is a
> glitch in the mpeg stream but it clears up.
> 
> I turned off the filters since the directv output is already heavily
> filtered. It seems to be a little sharper. It looks much better than
> the capture from the SAA713X cards, and now all files are mpegs and
> can play on anything.
> 
> Thanks for the driver!

The mythtv-users list is just so darned noisy that it is impossible to 
monitor effectively.  However if I know there's something going on that 
I should read then I'll search my archive and of course I found your 
thread there.

I must have missed the cx25840 warning message before; sorry about that.  
Clearly that was key to the problem.  I also didn't realize that you 
weren't using the tuner but rather a video input.  If the device is 
being fed an NTSC video signal but trying to encode it with PAL geometry 
then yes I imagine you're going to see strange jumpy behavior as it 
tries hopelessly to match up 50Hz vs 60Hz video.  Glad you nailed it 
down.

I'm a little confused about how you had "ATSC" selected in mythtv.  
That's a tuner-specific setting, IIRC.  My own setup at home currently 
has two tuners.  One is an ATSC (pcHDTV HD-3000), the other is a PVR 
USB2 device.  The parameters to set up one have nothing to do with the 
other, so I don't understand your ATSC vs NTSC point above.

On to reply to your other message...

  -Mike

-- 
                        |         Mike Isely          |     PGP fingerprint
     Spammers Die!!     |                             | 03 54 43 4D 75 E5 CC 92
                        |   isely @ pobox (dot) com   | 71 16 01 E2 B5 F5 C1 E8
                        |                             |