[mythtv-users] nVidia GF4 mx440 tv-out optimization

[blacklion at blacklion.org]

I've actually seen this same problem.  I have a Chaintech 7NIF2 board
with the GF4 MX 440 S-Video out.  The desktop looks terrible, as
expected.  However, when I have the frontend running, I can see the
horizontal refresh flicker.  I have this hooked up to a Sony 27-inch
TV.  The TV has 3 A/V inputs.  Only one of the inputs has an S-Video
connector.  I have my HorizSync set to 30 - 50 and my VertRefresh set to
60.  I don't see this flicker when watching Live TV or videos.  I
haven't put in any images yet so I'm not sure how they look.  It's only
on the menu screens that I see a flicker.

On another note, I haven't been impressed so far with the Live TV
picture.  I'm sure there is more configuration that I could do.  I just
need some direction.  Here are the two problems I'm seeing:

1. Light colors and whites have hardly any detail at all.  They are just
so bright that all the detail is just washed out.

2. I'm not sure what to call it, but I see a lot of "jitter" or
horizontal lines during fast moving scenes on TV.  I've activated the
"Jitter reduction" option in the TV settings, but that doesn't seem to
help.

I've changed the following and I still see all of these problems:
NVIDIA drivers (several different versions, including the latest and
4363)
Compression methods (RTJpeg vs. MEPG-4)
Quality settings
Capture resolutions
Bitrates

My CPU in this machine is a AMD 2500+ Barton.  I'm using the frontend
and backend in the same machine.  My capture is an older Happauge BT878
card.  I don't this this is a CPU problem because I only have the one
capture card and I haven't seen a frame drop or the CPU maxed out.

If someone could point me in a direction, I would really appreciate it. 
I'd like to get all of the functionality out of my myth box that I can,
but I just can't watch Live TV with the poor picture quality.

BTW, I'm using Mandrake 9.2 with a 2.4.22 kernel.

Thanks,

--B


On Sat, 2004-03-27 at 19:12, Jarod Wilson wrote:
> On Mar 27, 2004, at 16:03, Dex West wrote:
> 
> > I guess I don't quite understand, I've got a standard
> > SVideo cable connecting my TV RCA 36" to my MX440 tv
> > out connector.
> >
> > What brand of video card do you have?  Is there a
> > difference in quality between Live Tv out of MythTv
> > and just viewing X?  I have not received my 350 yet so
> > I have not tried to configure Myth yet.
> 
> Ah. So you're commenting on the quality of the desktop. What you're 
> seeing is probably as good as it gets. Computer desktops weren't meant 
> to be shown on interlaced displays. Myth should look fine though, 
> because in contrast, it *is* designed to be run on an interlaced 
> display. If I drop to the desktop and try to do a whole lot of work (on 
> my Myth box hooked to a 27" analog set), my head starts to hurt, 
> because is constantly jittering up and down. TV looks great though. In 
> contrast, I have zero problems working on my Myth box hooked to my 
> HDTV, which uses a progressive-scan signal.
> 
> 
> > Thanks for the response..
> > --- Simon at the Threshold <dweller at the-threshold.org>
> > wrote:
> >> I've also got a MX440 and am using it to generate
> >> tv-out using a svideo
> >> cable.
> >>
> >> The obvious one when dealing with SVIDEO out is does
> >> your TV support
> >> anything other than the composite input?.  I had the
> >> same problem (crap
> >> quality) until I stuck the svideo connector to the
> >> svideo scart port.
> >>
> >> Simon
> >>
> >> Dex West wrote:
> >>> I know this has been discussed many times, but
> >> i've
> >>> searched through the archive and can't find
> >> anything.
> >>> So could someone help me with some key words to
> >> search
> >>> for?
> >>>
> >>> I've installed a gf4mx440 w/ tv-out on fedora
> >> core.
> >>> The Tv-out is connected with a svideo cable.  I've
> >>> followed Jarods howto this far.  The Tv-out works
> >> but
> >>> the quality is really bad.  It seams like a
> >> horizontal
> >>> refresh rate problem.