HDR Slight flickering (Workaround available)

It can get a bit confusing. Check this out:

So at 4K24Hz, you can get RGB or 4:4:4 only.

In your case (for your TV), I think the best option is 60Hz and Sync Playback to Display. Although Adjust Refresh Rate is sometimes needed to pass HDR metadata through (need to switch the mode sometimes; even if it’s the same mode to trigger the data to be sent through). Improvements being made here though.

Aha so since LG can’t do HDR at 4:4:4 we’re kinda out of luck :frowning:

You can probably do 4:2:0 at 4K60 and enable Sync Playback to Display. You’d lose passthrough, but the most tracks can be passed as 7.1 LPCM.

Is there a chance that the AMLogic chip could be made to support 4:2:2 or 4:2:0 at 24 fps?

The SoC isn’t the issue. The above chart is the best you will get from HDMI 2.0a. There’s some more information here: http://www.acousticfrontiers.com/uhd-101-v2/

I want to use passthrough audio so that’s not an option. I also want to 1080p24 movies to play in 1080p24 instead of 2160p60 (by not using auto change refresh rate)…
I did a little experiment: I installed “Kodi Callbacks” service which lets you do stuff on events.
I created an event to run when a movie playback is started that runs this script:

#!/bin/bash
sleep 4
string=$(</sys/class/display/mode)
if [ $string = “2160p24hz” ]; then
echo “2160p60hz420”>/sys/class/display/mode
fi

so basically when I start a 2160p24 movie it switches display mode to 60hz 4:2:0
I think that’s good enough for me. Let me know @Pleomin if you want to try it and need assistance.

I got it to work. I assume this also should be done for 25 and 30 fps footage?
something like

#!/bin/bash
sleep 4
string=$(</sys/class/display/mode)
if [ $string = "2160p24hz" ] ||  [ $string = "2160p30hz" ]; then
echo "2160p60hz420">/sys/class/display/mode
elif  [ $string = "2160p25hz" ]; then
echo "2160p50hz420">/sys/class/display/mode
fi

I don’t know enough of bash scripts to verify the syntax.

Good stuff.

Yeah you’re absolutely right. It’s not harder than that :slight_smile:
Hopefully there’ll be some update for the tv or kodi that fixes this but it’s better than nothing!
Thanks @sam_nazarko

I concur. For now I’m satisfied.

1 Like

Any news on a fix for this issue. I own an LG E6 and I’m thinking about buying this device. But an inability to correctly play back 4k files at native 24p is a dealbreaker for me. Currently using an Nvidia Shield and it can do this without issue

You can watch 4K content at the right Refresh Rate. There are however limitations with some LG OLED displays. There’s nothing we can do to resolve this as it’s not a Vero 4K issue.

But Kodi on the Nvidia Shield manages fine?

If you’re able to watch 4K content on your Shield fine, then you won’t have issues with the Vero 4K. The only LG limitation seems to be in regard to HDR.

Please can you clarify the exact query?

Sam

I dislike the shield because it doesn’t auto change resolution it’s upscaling is dreadful and I find it quite buggy. I am extremely interested in replacing it with one of your devices after reading the review on avforums because it can auto switch resolution and play files via Kodi at 24fps. However, I use Kodi on my Nvidia Shield and see no issue whatsoever with HDR content at 24fps on my oled tv.

I’m reading hear however that your device does have difficulty displaying HDR content at 24fps on LG Oleds. I just wanted to check if you were able to fix these issues. I don’t want to replace the shield tv with something which doesn’t display HDR content well on my tv. It’s sounding like you can’t fix the issues so I’m better sticking with what I’ve got?

Sorry – I don’t think I was clear.

If it works fine on your Shield, it will work fine on the Vero 4K. I was simply mentioning the limitations of HDMI 2.0a, both of which apply to Vero 4K and the NVIDIA Shield. I think the lines of this post have become a bit crossed. Can you play 24Hz 4K HDR on your Shield at the correct Refresh Rate?

There is indeed an occasional flicker when playing HDR content for some users, but it seems that this is not unique to LG OLED TVs or a limitation of them. I think I know what the problem is and will start a new post with a range of video playback improvements that I want to get in to the next update shortly.

There is now support for 12-bit output as well.

Hope this helps

Hi. Just to confirm that I do see this flicker in the bright areas of the picture. It’s fairly noticeable unfortunately. Looking forward to the playback improvements you’re working on in relation to this.

I believe this is already fixed.

The flickering was introduced by the OSD layer. See

It’s scheduled for inclusion in the next OSMC update. If you want to test now:

I’d appreciate it if you could test this and provide feedback before we release this as an update to other users. To test this update:

  1. Login via the command line
  2. Edit the file /etc/apt/sources.list
  3. Add the following line: deb http://apt.osmc.tv jessie-devel main
  4. Run the following commands to update: sudo apt-get update && sudo apt-get dist-upgrade && reboot
  5. Your system should have have received the update.

Please see if the issue is resolved.

I also recommend you edit /etc/apt/sources.list again and remove the line that you added after updating. This will return you to the normal update channel.

Ok. I’ll have a look tonight. Fingers crossed.

For what it’s worth the flickering only occurs in really bright areas of the picture. It can look like a pulsing area on white scenes especially.

sorry but that’s beyond me. I get as far as using nano to edit but when I try and write the file I get a permission denied error