HDR with Samsung TV and AMD Ryzen

    Firstly Libreelec is great, been using it since inception and thankful to see the support increasing and the time and effort that goes into it.

    I have an minor but irritating issue below:

    What: Samsung QE65T HDR only switching when I go into settings and either switch Game Mode On or Intelligent Settings On. Once on system stays in constant HDR mode, only switching off and on Game Mode or Intelligent settings triggers back to non-HDR mode. When playing SDR content or viewing menus in always on HDR colors as expected over saturated. Can consistently repeat behaviour. Librelec latest build.

    Setup:

    Librelec Latest Build stable build.

    AMD Ryzen 5600G Motherboard is Gigabyte Motherboard AS5201 AC (HDMI 2.1 Compatible, HDR compatible).

    Connection to Samsung via Direct HDMI 2.1 certified cable from HDMI port on PC (prior to buying new cable 4k content stuttered so I know cable is good).

    I did have it connected via a Samsung Soundbar to TV but now with the HDMI 2.1 cables I e-arc the sound back to the soundbar for ATMOS that all works well.

    Diagnosis:

    Auto switching of HDR content is not happening when triggered by the player. Once playing the content and switching on intelligent mode or game mode on TV system then recognises the HDR10 content and it looks great as expected and TV shows in top corner UHD and HDR. Libreelec does recognises the display in the system as being HDR10 compatible and content as such. It Seems some kind of metadata or trigger not being passed to Samsung or my setup in Kodi is broken. I followed the HDR wiki page and setup up whitelist modes per that wiki page.

    Not sure if you want modetest output or other log files. Let me know if more detail needed.

    lAA520I ACA520I AC520I AC

    Spent more time on this now further tweaking.

    Set Display in Settings to 3840x2160P refresh rate 100 or 120HZ HDR mode kicks in on reboot 100% of the time but does not switch off (ie revert display to non-HDR when exiting HDR content) so menus over saturated SDR content likewise.

    Set Display in settings to 3840x2160P refresh rate 60Hz it will not kick into HDR mode on reboot (Note this was the default setting when I first installed LibreElec). Through combination of mode switching I can sometimes get HDR to work but its is perhaps more luck than judgment.

    Note per the wiki I did not include the 100 or 120Hz in my whitelist settings. Adding these modes does not make any difference to the behaviour ie it does not revert back to non-HDR mode.

    Conclusion:

    Using the 3840x2160P @100 or 120HZ system will boot and auto detect HDR content but not switch back to non HDR later. with 60HZ refresh it will not switch to HDR.

    Switch in Player is set to use Display HDR HDR works @100-120HZ . Use KODI path to play HDR HDR does not kick in even with 100-120HZ set.

    HTH

    One other tweak I tried per the WIKI

    Recommendation: Set the Adjust Refresh setting to "On Start/Stop"Recommendation: Set the Adjust Refresh setting to "On Start/Stop"

    I thought this might flick the HDR on/Off. Note setting this setting will not enable the HDR.I think the issue is mode switching to 100-120HZ enables HDR on this display but the native rate of the content is less than this.Yet if I play the content at the native rate it is not enabling HDR as it is not equal to 100-120HZ the panel is expecting.Thats my logical reasoning not my technical brain as I don't know the ins and out.

    Hi,

    Slept on the issue a bit more research I resolved this morning.

    Samsung Q80T sets have one HDMI port that is setup to receive 4k @100/120HZ @2.1GBPs 2.1. The others apparently do not (Absence by omission) and supports AMD freesync et al Link https://www.avforums.com/reviews/samsun…t-review.18207/

    I plugged the cable into that port and the switching works as expected. Playing HDR content switches to HDR. When the content stops mode switches back to non-HDR mode. No other changes made to the setup. Hope my couple of posts help others troubleshoot/setup their Samsungs.

    Moral of story, regardless of what the system (no fault of Libreelec) tells you the display will support check the HDMI port compatibility with your display and plug the cable into the right one. Rather than seeing it as a gaming port (as marked) which you plug your nintendo/PS4/5 into :)