LE 13 N stopped smooth playback on 4K on May 11 nightly?

    Hello,
    Just curious, here the last nightly to play back smooth video is LibreELEC-RPi4.aarch64-13.0-nightly-20260511-f6935c9 which still runs perfectly.
    Any version after that has issues with the 4K HDR stuff that we see much of.
    Is this a known issue, a breaking change, or something we need to tweak?
    Thanks for a great bit of code an any hints if there is time.

    Quote from MatteN

    I update almost daily and i dont see any problems.

    Thanks. Could of course be something wrong here I guess, but the (causation / correlation) fact that it works perfectly with any build

    before May 12 throws me. May I ask if you are on Raspi 4 also?

    Quote from Da Flex

    houser Do you use sub-titles or any other type of display overlay?

    Typically not, but this issue persists with or without subtitles switched on or off.

    It also works without issues with subtitles switched on or off on LibreELEC-RPi4.aarch64-13.0-nightly-20260511-f6935c9

    Quote from houser

    Just curious, here the last nightly to play back smooth video is LibreELEC-RPi4.aarch64-13.0-nightly-20260511-f6935c9 which

    That is the last build before the reardonia patches were added to LE.

    Those patches are a fairly significant rework of rendering (especially HDR).

    The overlay (including subs) now goes through a SDR->HDR tonemapping path which is more expensive (although should produce better colours), although I'd expect that to only affect video when overlay is active (but maybe it's not disabled when not needed).

    Do you have an issue with 4kp24 or 4kp60 videos?

    Can you post a debug log when playing a file with the issue? May conform exactly which settings you are using.

    Also output of "kmsprint" when playing a video (with and without overlay active).

    Quote from popcornmix

    That is the last build before the reardonia patches were added to LE.

    That indeed sounds like a decent cause and correlation.
    I am typically not using anything higher than 30fps.
    I am travelling a bit this week but will try to get to the debug logs in good time.
    May I ask if there is a possibility that our 8GB memory Raspi 4 will not be able to handle this new code?

    Quote from houser

    That indeed sounds like a decent cause and correlation.
    I am typically not using anything higher than 30fps.
    I am travelling a bit this week but will try to get to the debug logs in good time.
    May I ask if there is a possibility that our 8GB memory Raspi 4 will not be able to handle this new code?

    I have it running on 8, 4 and 2GB Pi's, no problem.

    Quote from houser

    May I ask if there is a possibility that our 8GB memory Raspi 4 will not be able to handle this new code?

    Worst case, it should be possible to add a switch to choose the previous behaviour (no sdr->hdr tonemapping), so you will be no worse off than before.


    But currently we're not sure of the cause. If it occurs without sub or other OSD, then it may be something else entirely.

    And it seems not everyone is seeing an issue, so we need to work out what's different in your case.

    Just updated my Pi4/8GB to 13.0-nightly-20260525-6a78312, playing Avatar; The Way of Water (2022)(UHDBD)(x265 10bit HDR DV) 2160p (70+GB) with .srt subtitle works without any problems.

    Quote from houser

    Hope this helps for now .

    Nope. Please share the debug logs. These will hopefully allow us to deduce what configuration and code-paths are being used, which is not apparent from the blah blah HDR/DV blah artefact blah waffle.

    A few questions:

    Is the non-smooth video blatant or subtle? Is it a frame drop every few seconds or multiple per second?

    Do the stats (ctrl-shift-o) show increasing skip: and drop: counts (note: a few skips when overlay appears is normal, but it should then no longer increment. Also this doesn't seem to catch all forms of skipped frames).

    If you disable "Adjust display HDR mode" in settings/player/video does it make the video smooth (at the cost of incorrect colour)?

    Does your display switch to a 4kp24 mode when playing 4kp24 video?

    Can you confirm the have the following settings:

    system/display "Set GUI resolution limit": 1080

    player/videos "Adjust display refresh rate" : "On start/stop"

    player/videos "Sync playback to display" : "Off"

    player/videos "Allow using DRM PRIME decoder" : "On"

    player/videos "Allow hardware acceleration with DRM PRIME" : "On"

    player/videos "PRIME Render Method" : "Direct to Plane"