[mythtv-users] E: nvidia new drivers hdtv/interlacing, any benefit for us non HDTV people?

Thomas Börkel thomas at boerkel.de
Mon Jul 5 09:20:20 EDT 2004


HI!

J. Donavan Stanley wrote:

>>> It's highly dependent on the shows you watch,  most shows I watch 
>>> look perfect as long as I have the A/V sync turned on, those that 
>>> don't look 
>>
>> You mean the experimental A/V sync? What about jitter reduction?
> 
> A/V sync requires jitter reduction in 15.1, recent CVS builds have the 
> two separated if memory serves me.

I did not try A/V sync, yet. What does it do exactly? For me, audio is 
in sync with video, as far as I can tell.

IMHO jitter reduction reduces jerky background motion (camera sway). Do 
I assume right?

>>> fine with kerneldeint added to the mix.  The quality exceeds that of my 
>>
>> Why do I need kerneldeint do output interlaced video to an interlaced 
>> device?
> 
> The signal itself is interlaced, but AFAIK in order for the interlaced 
> video to look proper you need to 1) output a TV sized signal with no 
> scaling, 2) Play the video back at double the frame rate synced with the 
> vblank(vsync?) so that the fields are displayed properly.
> 
> I used to be all hot and heavy to "fix" this in Myth, then I got my 
> XF86config in order, turned on kerneldeint (though it's rarely needed) 
> and discovered that It really wasn't an issue so I concentrated on other 
> things.  For the 5 channels I receive via my spiffy new antenna, Myth by 
> far exceeds what I see if I just connect the antenna to the TV.  For my 
> DTV channels you'd be hard pressed to find differences.

I have 2 problems, I hope you can give me some advice on that:

1.
With the old NVidia driver, I could not watch car racing, because the 
cars jumped. With the new driver, this jumping is gone. I think that's 
because I set the Flicker Filter in the nvidia-settings tool to 1 (0 
does not work correctly), where the default is 127 (out of 255).
But the motion of the cars still looks blurry.

2.
When I watch shows from NTSC land, that have been converted to PAL, 
motion and panning is jerky.

I have big audio buffer on and also enabled jitter reduction. Without 
that, background motion is always jerky (even for native PAL shows).

What else can I do? Will A/V sync and kerneldeint help eliminate blur 
and jerky motion?

It's not a problem of the captures, because it looks perfect with the 
PVR-350 TV-out, which I do not use regularely at the moment, because 
it's not that stable.

Thanks!

Thomas




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