HDR Banding issue

[aj_hix36]

Should DitherDepth be set to 10? My guisettings.xml reads ditherdepth default=“true” 8 ditherdepth.

[mule]

Please open another thread because this one relates to banding issues. Thanks!

[sid6581]

I thought we need the test build to be able to set and test the parameters? However, I did a reboot and reverted to 444,10 and upon playback (with round1 allegedly set per default) nothing changes, still banding. But when I do

echo “round1” | sudo tee /sys/class/amhdmitx/amhdmitx0/debug

I see the same improvements than with dither1. Maybe I wasn’t clear about that, because setting round1 helps - there’s just no additional improvement over dither1. And that’s fine, it now looks indistinguishable from the output my Sony UBP-X800 gives.

My configuration btw: Vero 4k -> Denon X1200W -> LG E6 OLED

[Martorias]

Ok I got it working now, not sure what was wrong.
I did a reboot with everything turned on and I had the usual banding. I went into the sys/class/amhdmitx/amhdmitx0 folder and
Sudo echo dither1 >debug brought back the flickering, dither0 fixed it.
Sudo echo round1 >debug fixed the banding. Round1/0 didnt seem to matter. However I have to set it manually för every video I play, Ill automate it for now but great progress Sam!

[sam_nazarko]

@Theetjuh

Mar 16 17:50:30 vero4k systemd-modules-load[160]: Module ‘amlvideodri’ is builtin

Mar 16 17:50:30 vero4k systemd-modules-load[160]: Failed to find module 'meson-ir’

Mar 16 17:50:30 vero4k systemd-modules-load[160]: Inserted module 'mali’

Mar 16 17:50:30 vero4k systemd[1]: systemd-modules-load.service: Main process exited, code=exited, status=1/FAILURE

Mar 16 17:50:30 vero4k systemd[1]: Failed to start Load Kernel Modules.

Mar 16 17:50:30 vero4k systemd[1]: systemd-modules-load.service: Unit entered failed state.

Mar 16 17:50:30 vero4k systemd[1]: systemd-modules-load.service: Failed with result ‘exit-code’.

Try updating again – this should be resolved. Not aware of why you’d experience problems with Bluetooth however. It could take an hour for this update to reach your mirror.

I need more of a consensus from others before I can make further changes to rounding and dithering defaults; otherwise it needs to be left as-is.

Cheers

Sam

[sam_nazarko]

@Martorias

Ok I got it working now, not sure what was wrong.

I did a reboot with everything turned on and I had the usual banding. I went into the sys/class/amhdmitx/amhdmitx0 folder and

Sudo echo dither1 >debug brought back the flickering, dither0 fixed it.

Sudo echo round1 >debug fixed the banding. Round1/0 didnt seem to matter. However I have to set it manually för every video I play, Ill automate it for now but great progress Sam!

Thanks for this report.

I’ll send you a PM shortly with some test builds and debugging instructions. It looks like we can resolve this pretty quickly.

[mule]

I can confirm the findings by Martorias. The latest update did not solve the banding. Only setting “round1” manually while playing a movie solves it.

[sam_nazarko]

@sid6581

I thought we need the test build to be able to set and test the parameters?

The sysfs parameters can now be configured using the latest stable release, and as such, you don’t need to use any test builds at this point in time.

[sam_nazarko]

@mule

I can confirm the findings by Martorias. The latest updates does not solve the banding. Only setting “round1” manually while playing a movie solves it.

Thanks for the extra datapoint.
If round1 fixes it, then we can fix it, no problem.

It might take a day or two to work out what’s going on however.

[mule]

Ah then there was a misunderstanding: I thought that the latest update should already had it integrated.
But great to hear that it should only be a matter of one or two days to solve it finally! Just tell us if you have something to test and we will give it a shot.

Once again thanks for you ongoing work!

[sam_nazarko]

@mule

Ah then there was a misunderstanding: I thought that the latest update should already had it integrated.

It should.

So either:

• This isn’t working / something needs to be set first
• The results vary for users.

There are still people reporting no banding whatsoever with 4K HDR, which is even more puzzling.

I’m looking in to this.

[mule]

If I remember correctly: Everyone who has banding issues with 4k HDR material and tried the new debug options confirmed in this thread:
a) round1 solved the issue but has to be set every time after you start a movie
b) the latest update did not solve the issue. Once again you have to set round1 manually every time you start a movie.
So in my opinion it does not vary for users who are having the banding issue.

[Martorias]

I did my old workaround v2.0 - kodi callbacks setting round1>debug all good now!

[MRK]

Hi everyone, Hi Sam.

I just wanted to say by joining your forums instead of reading only that i also meet that HDR Banding issue. I just bought Vero 4K 1 week ago and am waiting for even a beta fix and know some friends who are eager to jump but waiting for my go.

I can’t do your tests since i don’t have the time or enough knowledge to mess with it with repo’s and ssh. As many buyers, i only want a fully functional 4K HDR Hevc kodi player.

I m using Vero 4K > Onkyo RZ710 > LG EF9500 Oled

Thank you guys for sorting this out.

Btw, i have a problem with hdmi arc blocked when Vero 4K is hooked but that’s for another thread.

[sam_nazarko]

@mule

If I remember correctly: Everyone who has banding issues with 4k HDR material and tried the new debug options confirmed in this thread:

a) round1 solved the issue but has to be set every time after you start a movie

b) the latest update did not solve the issue. Once again you have to set round1 manually every time you start a movie.

So in my opinion it does not vary for users who are having the banding issue.

We had a couple of users report no difference / no improvement. Not sure if it was tested correctly though.

What’s interesting is that round1 is set, but I think there are some codepaths where it doesn’t work. I can investigate this tomorrow after some rest.

@Martorias

I did my old workaround v2.0 - kodi callbacks setting round1>debug all good now!

Do you see regressions for non HDR content? Because it’s very, very easy for us to poke from userspace (Kodi) to fix this up, and that was the intention of exposing these register settings via sysfs.

@MRK

I just wanted to say by joining your forums instead of reading only that i also meet that HDR Banding issue. I just bought Vero 4K 1 week ago and am waiting for even a beta fix and know some friends who are eager to jump but waiting for my go.

Don’t worry, you are just a couple of days too early. We will have this all solved shortly. It’s already proven that the banding and flickering can be removed; we just need to work out the specifics.

@MRK

Btw, i have a problem with hdmi arc blocked when Vero 4K is hooked but that’s for another thread.

Is this when Vero 4K is off? Try using the ‘Suspend’ mode.

Sam

[Martorias]

@sam_nazarko

Do you see regressions for non HDR content? Because it’s very, very easy for us to poke from userspace (Kodi) to fix this up, and that was the intention of exposing these register settings via sysfs.

Not from what I saw but I need to test more before im 100% sure

[MRK]

I noticed that even when Vero 4K was not on the power outlet (only hdmi cable on it), as soon as i unplug it from the AV receiver i get arc sound back on.

[clawforce]

I know this is off-topic to the HDR banding issues, but I have been having the same problem and eventually gave up and started using optical instead of ARC.

So long as the Vero 4K is plugged in, ARC gets screwed up. If i unplug the HDMI cable from the receiver, it will start working again. I have no clue why. Denon X4400 and LG OLEDE6P.

[Martorias]

Sorry but why do you use arc if you have the vero connected to your amp?

[clawforce]

TV passes back sound from internal apps including Netflix, Amazon, Youtube and others, which use HDR and Dolby Vision natively.