With some 4K HDR content I am experiencing the color distortion at pink and green colors as it was discussed in other threads already (if one suspects it had to do with Dolby Vision, I read something that at least since the April 2024 update it should be supported).
I am wondering if there are some setting tweaks in OSMC or on Kodi/Linux level (e.g. regarding color space) which might help getting rid of this.
My display device is an Optoma UHD38x projector. I guess my HDMI cable is rather not the culprit: HDMI 2.1, 8K Ultra High Speed, 48Gbps, 4K 120Hz.
Update: Turns out the projector itself doesnât support Dolby Vision. I am not experienced enough how the signal processing for this works, however is it maybe possible to kind of exclude forwarding of Dolby Vision âmetadataâ in a video signal coming from the Vero V and hand it to the projector in such a way that still as an HDR signal without Dolby Vision, the colors are reproduced as intended? As in my first post, my question goes in the direction of twaeking the settings inside the Vero, respectively.
It should just work. But you can turn off DV and output HDR10. See Disable Dolby Vision - #13 by pinn73
Still no luck. I also found my projector does not support HDR10+ but only HDR10 and HLG, so I have currently set my Vero V as follows:
- Settings->Player->Videos->Adjust HDR mode display - ON
- Settings->Player->Videos->hdr processing - set to âForce HDRâ
- Settings>System>Display> Manually set a displayâs HDR support - set to âHDR10 and HLGâ
Maybe worth mentioning that among others, the issue becomes particulary pregnant when using the Aerial screensaver: Some of the videos show the correct HDR colors, others look like a negative picture with the color exaggerations mentioned before.
So that combination of settings works for you?
For the record:
Adjust HDR mode display does nothing (we need to get rid of it).
Force HDR stops Vero sending DV output ie it subtracts DV capability.
Manually set a displayâs HDR support adds those capabilities where the EDID does not include them - useful when a AVR doesnât support HDR10+ or DV.
Screensavers wonât be the right colours when playing DV content to a DV screen but should be OK if youâve disabled DV (which you have, it seems).
If you want more advice, please post full debug logs.
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just to piggy back this, Iâve noticed some DV titles exhibiting the same issue. To fix it, I then need to open up other DV titles until they finally display correctly. I can then go back to the original title and DV will kick in correctly. Canât reproduce as quite a random occurence.
No it doesnât. Here are the debug logs (last Aereal screensaver previev caught one of those showing false colors):
https://paste.osmc.tv/etozagoxox
From your log, I gather that the Aerial screensaver actually plays 4k videos rather than the random graphics of screensavers of old.
The problem is, these are DV Profile 5 videos. If you start a DV video while another one is playing the video processor doesnât get set up correctly. Itâs something we observed before but thought would be a niche case and didnât spend any time on it.
If you disable the screensaver, are you able to play DV files OK (maybe after first playing a non-DV file if it doesnât work first time)? If so, my theory looks good and weâll see what can be done about it.
That is correct. And one can turn 4K video on or off, same as with HDR. AFAIK there are no stills anymore at all.
I never did that consciously. The screensaver only kicks in if that is not the case. Or did you mean the screensaver timing is too short from one video to the next one, so the playback device cannot consider the changes?
I disabled the screensaver now and from what I can see any other DV videos play as they should, without any color shift. My projector falls back to HLG then, and it seems it does it OK.
What I mean is, if the screensaver is playing a video and you start a ârealâ video the video chain is not re-set properly.
Thanks for checking. Iâll try installing that screensaver, but I note the videos are HUGE!
could this be related to the issue I noted above?
That for sure never happened on my side, since the screen saver only works when no other video is in the chain at the same time. As soon you press any key, be it on the remote or on a keyboard, the screensaver instantly goes away, and the screensaver only kicks in again when the Vero is idling.
On a side note, when I stop the screensaver and afterwards, play a video title the latter shows up fine, means meanwhile I can only reproduce the problem with the videos from inside the screensaver.
One can also download only some of them out of the addon (settings) itself and then turn it to play offline. In that case, only the ones downloaded will be played. However note that not all of the videos play with false colors so that might be a bit tricky. If you have set the device caching well and have at least a 100 Mbit/s line it should work online as well.
In my case I donât think so. Currently here the problem only seems to occur with some of the videos of that screensaver, however since I cannot tell which kind of formats the problematic videos are, I suspect that if any other DV video with the same metadata comes across it might also show this behavior, be it from a BluRay, local network stream or whatever. Did you make sure you set the vero correctly, especially regarding these 2 settings, assuming your display device doesnât support DV?
I think you provided a clip of Kitchen that I have here which repeatedly doesnât play as DV since we implemented TV-led playback. It seems FFMpeg doesnât recognise it as DV. So do you have other titles with the same problem?
Iâm hearing @timzettâs only getting wrong colours from the screensaver and his regular videos play OK so seems to be a different issue. The screensaver could be bypassing a bit of Kodi that identifies the codec.
Leave it with us.
This only happens on tv files, so when one finished and I go to UI to select the next, the issue occurs. To my mind this seems similar to what @grahamh mentioned about the decoder not kicking in, as when I watch movies (not back to back ofc), I never experience this issue. Does that make sense?
I agree
Did you have the chance to test a bit or maybe even reproduce what I see?
Not yet.
OK, so Iâm running into a problem. It looks like Apple decide my internet connection is not fast enough for 4k videos and only send me 1080p AVCs so no issues here. Your log says you are getting 4k DV streams. I need to see if I can work round that.
Ah! So thereâs a setting to enable 4k videos. What happens if you turn that off? Can you live with a 1080p or 4k SDR screensaver?
I can survive with 4K SDR 
However there were 2 aspects for me in this thread. First aspect was that this screensaver, along with both 4K and HDR on could make it possible to get the most out of my display device`s capabilities (which would be enjoyable to watch). Second aspect was that this false colors in some of the videos might maybe indicate a HDR glitch in OSMC, maybe in conjunction with the Vero V (I am not aware of any other devices being capable to offer 4K HDR and even DV with OSMC). What I could imagine is that the videos played by the screensaver contain different HDR metadata, for instance HDR+, HDR, HLG and/or DV. And maybe in a specific scenario or call it sequence, OSMC might have issues to âseamlesslyâ switch over to the correct HDR decoding. BTW I noticed that itâs always the same video sequences showing the false colors.
In short: maybe it would have been worth it to find the root cause and in the best case, even eradicate it.
I just offered you a workaraound while we look into it. Iâve found the Hong Kong clips consistently cause this because the metadata is bonkers. I think Apple have lost the manual Dolby gave them to make DV streams. Weâre working on a fix.
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@grahamh any idea about this? Ta