4k resolution makes TV turn black on/off

  • My previous system also had this issue, it is a bit weird so i will do my best to explain.

    It happens when i turn kodi menu resolution at 4k (4096x2160p) at 100 refresh rate. Which was also the resolution the system picked after installing. As far as i knop this resolution is only for the Kodi menu right?

    The weird thing is when i leave the Kodi menu on for a while, the screen turns black now and then for about two seconds. Also i see a bit of a horizontal green line. Most of the time when i start a video this stops (also 4k). Something is happens a lot and sometimes only one time, it seems really random. I haved check the cpu/gpu temp, that is not the problem.

    When i dial the resolution back 1920x1080p at 100 refresh rate. This problem goes away. My tv is a LG Oled E9.

    Any ideas why this happens?

  • Two things..

    - What device are you using to run LibreELEC on?

    - Why use 100Hz when a typical HTPC runs at 60Hz, and does the problem go away at 60Hz?

    On a 3200G / 8GB / 120GB SSD / MSI B450 Mortar MAX.

    And why 100Hz well, not really a reason other than the fact that the system picked this one by itself. So i thought why not?

  • You may want to keep the GUI at the same level as the maximum video rate, which is basically 60Hz. I don't know of any videos doing 100Hz/fps.

    The Linux system underneath may think it's cute, but Kodi wasn't designed for 100Hz video output.

    Hence my suggestion to test and limit the video output to 60Hz.

  • You may want to keep the GUI at the same level as the maximum video rate, which is basically 60Hz. I don't know of any videos doing 100Hz/fps.

    The Linux system underneath may think it's cute, but Kodi wasn't designed for 100Hz video output.

    Hence my suggestion to test and limit the video output to 60Hz.

    I will test that, a little other weird thing is when i go to System (Settings) it always asks "do you want to keep the settings?" . Is that normal?

    I am also a bit curious what the best settings for a Oled 4K TV are with regards to Deinterlacing / Scaling / Change Refresh etc. Do you have any tips with regards to best practice settings? My Kodi system has more than enough power, so i would like to use Kodi in the most optimal way :)

  • Keep in mind that you have to use a 48Gbps Ultra High Speed HDMI cable if you want to use the HDMI 2.1 modes (8k or 4k > 60p).

    But there's not much point in using more than 60p on a mediacenter, these high refresh rate modes are mainly useful for gamers who want to have 100-120fps in their first person shooters.

    so long,

    Hias

  • when i use 4096x2160p at 60 the screen turns Black a lot more. So the problem becomes worse. When i pick 3840x2160p at 60, i haven't seen a black screen so far.

    A i totally forgot about the cable, so probably the cable (which is old) isn't good enough and could be the problem.

    Should i be able to use 4096x2160p?

    I get what you are saving about "why 100?" of course.

  • Just stick to 3840x2160 - that's the native resolution of all UHD sets (and usually marked as preferred in EDID).

    Run the GUI at 50 or 60Hz and whitelist the 23.98/24/50/59.9/60 Hz modes (better NOT the 25 and 29.9/30Hz modes as that may cause havoc with interlaced content).

    As for 1280x720/1920x1080 you have to check yourself if you also whitelist them (and let the TV upscale) or let kodi do the upscaling to 4k.

    The LG OLEDs have pretty good scalers so I'm not really sure if kodi is able to do a better job.

    so long,

    Hias

  • So if i whitelist a resolution the TV handles upscaling and NOT whitelisted than Kodi will do it?

    I would have thought this would be the other way around. Good to know!

    So if 3840x2160p at 60 works, no need to buy a better cable? i was planning on buying an AudioQuest Pearl HDMI cable.

    Do you have any suggestions with regards to Deinterlace method, video scaling method and adjust refresh rate? I would think that the settings needs some tweaking looking at the tv you use. right?

  • So if i whitelist a resolution the TV handles upscaling and NOT whitelisted than Kodi will do it?

    Kodi's whitelisting logic is a bit complex/confusing but, yes, basically it's this way. If you whitelist a display mode / refresh rate then Kodi can use that if "adjust display refresh rate" is enabled in the player settings (set it to "always" or "on start/stop").

    So kodi can eg switch to 1080p23.9 if you play a HD movie.

    so long,

    Hias

  • Kodi's whitelisting logic is a bit complex/confusing but, yes, basically it's this way. If you whitelist a display mode / refresh rate then Kodi can use that if "adjust display refresh rate" is enabled in the player settings (set it to "always" or "on start/stop").

    So kodi can eg switch to 1080p23.9 if you play a HD movie.

    so long,

    Hias

    Okee will do all that, thanks!

    And with regards to Deinterlace method, video scaling method?

    I mean "VAAPI Bob" sounds pretty cool, but no idea if it is the right choice ;)

  • And with regards to Deinterlace method, video scaling method?

    I mean "VAAPI Bob" sounds pretty cool, but no idea if it is the right choice ;)

    I can't comment on that as I'm using RPi which has different (software only) deinterlacers.

    "Bob" may sound cool but actually is a pretty simple / poor deinterlacer (have to use SW bob deinterlace here on RPi4 and deinterlaced SD material looks terrible).

    The "yadif" and other deinterlacers (not sure what's actually available on PCs) should work a lot better.

    so long,

    Hias

  • I can't comment on that as I'm using RPi which has different (software only) deinterlacers.

    "Bob" may sound cool but actually is a pretty simple / poor deinterlacer (have to use SW bob deinterlace here on RPi4 and deinterlaced SD material looks terrible).

    The "yadif" and other deinterlacers (not sure what's actually available on PCs) should work a lot better.

    so long,

    Hias

    Too bad you use a RPi4 ;)


    I don't have "yadif".

    Deinterlace method: VAAPI BOB, VAAPI Motion adaptive or Off.

    Video sclaing: Lanczos3 Optimised, Spline36 optimised, Lanczos 2, Bicubic, Bilinear, nearest neighbour or Auto

    No suggestions looking at the options?

    Is there also an indication on audio delay through HDMI? The mouths and audio are not an 100% in sync. So by how much should i adjust the audio? I get it depends on the tv / setup. But there probably is a general indication on audio delay when using HDMI, right? I think it is somewhere between 0,1 and 0,250 sec. Maybe i am a bit of a perfectionist, but i just like to have (technical) things as good as possible :) 99,5% is just not doing it for me :p

    Edited 3 times, last by Operations (April 19, 2020 at 3:10 PM).