[mythtv-users] judder problems with nvidia 384.59 work round

[John Pilkington]

On 14/08/17 09:59, jksj wrote:
> Related to the existing thread Judder problems with nvidia 358.16 but I 
> have raised this as a separate thread as it only offers a work round.
> 
> Recently bought a Nvidia GT 1030 which requires the latest driver (384) 
> and started to suffer from really bad judder.
> 
> Puzzled by the fact that other apps like Kodi were judder free but 
> preferred to stick with mythfrontend.
> 
> Guessed eventually that Kodi worked because it was using a fixed frame 
> rate unlike Mythtv which was attempting to dynamically adjust it.
> 
> So I am now judder free by not following the instructions in 
> https://www.mythtv.org/wiki/User_Manual:JudderFree
> 
> Specifically
> 
> Fix the refresh rate before running the frontend, for Freesat or 
> Freeview in the UK the following works.
> 
> nvidia-settings -a 0/CurrentMetaMode="1920x1080_50 @1920x1080 +0+0"
> 
> Then in the “Video Mode Settings” page referred to in the wiki, 
> _un_check “Separate video modes for GUI and TV playback”
> 
I have 854.59 too, with a GT 710, and have settings that look quite 
similar, eventually saved from the NVIDIA config GUI; sometimes I can 
get it to come out the same twice.

  Section "Screen"
     Identifier     "Screen0"
     Device         "Device0"
     Monitor        "Monitor0"
     DefaultDepth    24
     Option         "Stereo" "0"
     Option         "nvidiaXineramaInfoOrder" "CRT-0"
     Option         "metamodes" "HDMI-0: 1920x1080_50 +1024+0, VGA-0: 
1024x768_75 +0+0"
     Option         "SLI" "Off"
     Option         "MultiGPU" "Off"
     Option         "BaseMosaic" "off"
     SubSection     "Display"
         Depth       24
     EndSubSection
EndSection

But I still have the defect I've mentioned before. In HD playback during 
pan/tilt there is a perceptible horizontal divider, not always in the 
same position, between two good sections of the picture.  It looks as if 
it ought to be kept off-screen by syncing the processing to the TV 
display, but 'X server XVideo Settings' and ~/.nvidia-settings-rc both 
claim that this is being done.

I suppose it might be relevant that I'm using
'mythfrontend -nw --geometry 1920x1080+1024+0' for the tv, with 
'mythfrontend' by itself giving a windowed 1024x576 display on the monitor.

Is this kind of defect one that other people see - and is there a way to 
stop it?  upnp does give a workaround for me.

John P