HDR Banding issue

Help and Support Vero 4K / Vero 4K +
61

@mule no i never got a chance, kids and all.
@captainmoody yes there are, kinda. Be wary that its a test build so things could go wrong and you might have to reinstall (probably not)
To test this update:

  1. Login via the command line6
  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

Your system should have have received the update

Then you try to commands in this thread via ssh while watching something

62

I just tested “Linux osmc 3.14.29-63-osmc” with 444,10Bit: out of the box there are no changes compared to the stable build. But if I execute

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

during playback, there is an improvement. Tested with Martorias’ clip (banding alomost gone) and beginning of Inception (Sky now almost “pixel-free”).

64

Tried it with the latest build and there’s definitive improvement! However, not until I changed the parameters via bash.

dither1 -> Clearly visible
dither0 -> No improvement
dither1 + round0 -> Some slight additional improvement
dither1 + round1 -> No improvement

The last two are more subjective, dither1 is what does it. I also tried to set round0 and round1 before doing dither1, those seemed to do the same thing as dither1 alone…

And I also tried with 444,10 and 444,12 which made no real difference to me (but were output according to my AVR).

65

Thanks @Martorias
I will try and test this evening

66

That’s odd — and possibly suggests there won’t be a uniform way to fix this for everyone.

You should not need to install the test build now, as I set round1 by default and included this in the 2018.03-2 update on the offchance it resolved things for people

Sam

67

@sam_nazarko I had two updates install last night, one after the other. Not set to use any testing repo.
Do the dither/round commands work with these?

68

Yes.

69

My Panasonic never showed flickering or banding on any test material so it will be interesting to have a play with those commands and see what happens

70

For an average Joe who just wants to watch 4K HDR films with no banding - what do I need to do ?
I have no idea what all this command line stuff is or how to do even do it.

I’m currently on Jan firmware (downgraded due to banding)

Is it safe to update yet on the Vero ?

Update:

Ok so I took the chance and updated to March 2018 2018.03-2 (based on Sams post a few up saying he’d included the fix in it)
Banding returned.

Can someone explain in layman’s terms how I can get rid of this banding please with step by step instructions of how to set this ‘rounding’ thing to 1

Cheers

71

For me, dither1 = hdr flickering returns.

72

I don’t think that was ever contended :slight_smile:

I’ll take a look at this again later this afternoon.

Sam

73

I think it would be worth anybody testing this to include the make, model & display type with their results. :+1:

74

Hi, do you know how to SSH to the vero?

75

Hi Martorias where you directing this post at me ?

If so yes I can, I just would like to know what the command to use to remove the banding for someone who had none prior to Feb update.
I don’t have an OLED so I don’t care for any specific fixes for flickering

76

Yeah, ok! The command tested here would be

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

You run that while watching a clip to see if there’s a difference.
I couldnt get it to work but ill mess around more tonight, hopefully it’ll help you. It feels lika a solution is close atleast

1 Like
77

Just tested with every possible option, round0, round1, dither0 and dither1 and I see totaly no difference in the output :cry:

I do have an error at boot since the update:

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’.

78

Sadly I can’t SSH into my device to test this banding fix, I choose not to enable it on first boot after downgrading firmware yesterday.

Now I can’t enable it, it appeared in sevices but there was no way to enable it.

I thought a uninstall/reinstall of the service would help… it errored out on uninstall.
Now it’s uninstalled but I can’t reinstall it, tried to do it, in says operation completed after installing, but it doesn’t install.

Absolute joke of a device this, can’t belive I spent £120 on a peice of hacky junk like this. It’s got to be the most unuser friendly device out there. Even basic things like uninstall and reinstall a component from the ‘app store’ don’t work on this piece of crap.

Guess I need to downgrade the firmware again and stick on Jan pre banding firmware.
Look forward to doing that it only took 4 hours to do yesterday in true Vero4K fashion… nothing worked as it should.

79

The service can’t be uninstalled because it’s a core part of OSMC. This is intentional.
Did you try enabling it under My OSMC → Services instead of re-installing it?

If you’re having any issues and you’d like to take a quick phone call, do let me know.

Sam

1 Like
80

Something seems to disrupt bluetooth or something like that, my cursor is behaving eratic since the last builds with 10bit 444 chroma enabled…

The problems are stacking it seems, will have a look at a restore to januari this weekend untill all the problems are resolved with banding etc.

81

And my IR remote stopped working, not sure if its random or related (it’s a harmony, still works on the TV/amp)