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

[John Pilkington]

On 15/08/17 18:02, jksjdevelop wrote:
> 
> 
> On 14/08/17 22:39, John Pilkington wrote:
>> 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

> 
> I have not experienced the  the tearing you describe. A quick google 
> shows various  Mythtv pages covering this but I think they maybe out of 
> date. I remember that it used to be necessary to run a desktop without 
> compositing but I think that is fixed now.
> 
> The bits that look different in xconfig are
> 
> Option         "nvidiaXineramaInfoOrder" "CRT-0" --which implies a VGA 
> connection
> 
> "metamodes" "HDMI-0: 1920x1080_50 +1024+0, VGA-0: 1024x768_75 +0+0" --
> 
> If you are driving a VGA connection have you tried re-synching the 
> monitor using its controls.
> 
> Do other apps like VLC or Kodi display without tearing?
> 
> 
Thanks for the response.  Yes, I have a VGA monitor and hdmi TV 
connected.  I've tried swapping the sync source, switching off the 
monitor and changing its frame rates, all with no noticeable effect on 
the solidity of the TV image.  I've tried vlc and smplayer with various 
settings, and mostly they have been worse.  I haven't been able to get 
smplayer to recognise the nvidia hdmi audio output, either.  I haven't 
tried Kodi yet.  upnp is working quite well for me but may well be 
device-dependent.