LE 11: Certain refresh rates cause washed out colours on Intel NUC I3-10110U

sjefsbamsemumsen · March 4, 2023 at 1:49 PM

When running at 4K/UHD or 1080p/HD at 50 Hz or above, the colours are displayed correctly with proper black. However, when changing framerate to 24Hz or lower, the colours look washed out and the blacks are dark grey. It looks almost like I turned on limited colour space (which is not on).

This happens both when I switch framerate in GUI or start a movie with 24 fps or lower. It also happens when playing HDR content.

I have also tried the latest nightly with same results.

Debug logs here: http://ix.io/4pUt

Log files are recorded while switching from 4K 50 Hz to 24 Hz and back again in System settings.

Running latest Kodi on Windows 11 on the same machine works fine, no colour problems there.

**smp** · March 4, 2023 at 2:45 PM

Look for "HDMI black level" or something similar in your TV's settings.

sjefsbamsemumsen · March 4, 2023 at 2:50 PM

I cannot see that TV settings are relevant as the colours are correct when running Kodi for windows on 24hz or any other settings. Kodi for windows plays everything correctly and runs on the same machine connected the same way.

sjefsbamsemumsen · March 10, 2023 at 9:30 AM

I just upgraded to LE 11.0. Problem is still present.

sjefsbamsemumsen · March 28, 2023 at 8:11 PM

Upgraded to 11.0.1, no changes.

**smp** · March 28, 2023 at 9:56 PM

Quote from sjefsbamsemumsen

I cannot see that TV settings are relevant as the colours are correct when running Kodi for windows on 24hz or any other settings.

Intel GPU driver for Windows may behave differently, e.g. it can support YCbCr output, in Linux it only supports RGB. Your issue has something to do with incorrect handling by your display of RGB full / RGB limited at 24Hz. Most modern TVs have a user selectable quantization range for RGB and also the Auto setting.

sjefsbamsemumsen · April 12, 2023 at 8:07 PM

I’ve been checking my TV settings and to the best of my knowledge it does not have any refresh rate specific settings. I can make 24 hz look right by changing the UHD colour settings, but then it messes up the input from other sources. Still strange that 4k 50 hz requires different settings than 4k 24 hz… Is that how it’s meant to be from a Libreelec perspective?

**Da Flex** · April 12, 2023 at 11:40 PM

Try Generic-legacy. You can use the update folder method to switch.

sjefsbamsemumsen · April 13, 2023 at 7:25 AM

Quote from Da Flex

Try Generic-legacy. You can use the update folder method to switch.

I thought that the legacy build did not support HDR, but maybe I read that incorrectly? I need HDR support (which is why I was/am running Kodi on Windows on this box).

**Da Flex** · April 13, 2023 at 3:27 PM

Not sure about HDR, but release notes don't say the opposite. Give it a shot.

**chewitt** · April 13, 2023 at 5:15 PM

Xorg (and thus the Generic Legacy image) does not support HDR

**Da Flex** · April 13, 2023 at 11:00 PM

Then it's probably a bug at color space or color buffer. The log doesn't show a related error, but mentions support of

GL_EXT_color_buffer_float
GL_EXT_color_buffer_half_float

So maybe the system picks the wrong one sometimes. We need more feedback from other users to be sure.

sjefsbamsemumsen · April 14, 2023 at 8:42 AM

Is there anything specific I can test to try to provide more information or logs?

**Da Flex** · April 16, 2023 at 7:12 PM

Quote from sjefsbamsemumsen

Is there anything specific I can test to try to provide more information or logs?

Unfortunately no. The only thing you can do ATM is trying an LE 12.0 nightly: Click!

sjefsbamsemumsen · April 17, 2023 at 3:41 PM

Tried the latest nightly real quick and it seems to behave just as LE 11.0.1. I did do some more testing with LE 11 vs windows over the weekend, and while I can get black levels to be OK from LE by changing the TV settigns, it also causes the entire image to be too dark.

**Da Flex** · April 18, 2023 at 8:35 PM

Thanks for testing. I gave this thread into developer discussion, but no feedback so far. This makes me think, it's eventually related to your setup, and not a bug. Maybe LE uses wrong EDID data, provided by your TV. So I suggest to experiment with custom EDID.

PS: jernej just told me that he debugs HDR issues ATM. So if it's a bug, it should be found during the next weeks.

**jernej** · April 29, 2023 at 8:26 AM

It should work again with next Kodi bump, some fixes were merged recently.

sjefsbamsemumsen · June 13, 2023 at 11:23 AM

Just a quick update: I downloaded the latest nightly (LE11)) yesterday to test and so far things are looking better. Have only tested a few UHD HDR movies, but so far the colours look as they should.

Thanks for the good work!