[noggin]

I don't think it is... I have a Zotac GT 720 (full specs). Looking at the specs, it can only output 2160p @ 30hz, but 1080p @ 60hz.

That would be correct. To my knowledge, as of today, the only video cards on the market with HDMI 2.0 support are GeForce 9xx (and now 10xx) video cards, all of which would otherwise be rather overkill for an HTPC)

At least this was the case a couple of months ago when I last researched it.

Though Kepler and Maxwell cards with HDMI 1.4b outputs can also output HDMI 2.0 2160/50p and 59.94p 4:2:0 video with the right drivers (at least in Windows, and I think also Linux). This was added in driver updates - and though nVidia don't claim their cards are HDMI 2.0 - effectively they do output one HDMI 2.0 format.

HDMI 2.0 included an additional 2160p UHD spec that allowed for 50 and 60Hz (aka 59.94Hz) output within the bandwidth constraints of HDMI 1.4b hardware - using 4:2:0 chroma subsampling. This isn't perfect for UI work and gaming, but since almost all consumer video is 4:2:0 (the only sources that aren't are movies you shoot yourself on your own cameras) it's less of an issue for video content.

This is also how some TV manufacturers were able to add 'HDMI 2.0' via a firmware update. They have basically just added 4:2:0 2160/60p and 50p functionality to existing HDMI 1.4 hardware - but because this mode is HDMI 2.0 only it is possible to claim HDMI 2.0 compatibility. (Sony and Samsung sets released in 2014 did this trick - many of them don't support 2160p at 50/60p with 4:2:2 or 4:4:4 chroma...)

[dhjgv]

Hi fritsch,

I finally had the time to test the patch.
Compiled LE 7.9 with the patch and it works like a charm!

[fritsch]

Submit it upstream if you want.

[dhjgv]

I don't need it anymore as I use full tab now for 3D. But making things optional is always a benefit in my opinion, so give it a go

[fritsch]

https://github.com/xbmc/xbmc/pull/10044 <- same for me

[Slowfoxtrot]

Hey guys Im trying to find the recommended settings in SPMC for "Lanczos3 - optimized" but I can't seem to find it on 1080p playback. Am I missing something?

Thanks

[xbmosx]

I just switched my Kodi htpc to Ubuntu on a NUC. I was able to get along pretty well so far with everything, but this still bugs me.

I'm running Kodi 16.1. GIT: C327C53 on Ubuntu 16.04.1 LTS and the NUC is hooked up to a Denon AVR via HDMI. TV is a Panasonic 55 Inch CXW704

If I understood correctly the recommendation is to put Kodi into 1080 resolution and activate refresh rate change. I can perfectly understand the reasons why scaling is supposed to be better with the TV than the NUC but I'm running into a strange problem here. For Kodi to stay in 1080 mode I have to put Ubuntu into 1080 as well, otherwise Kodi switches back to 4k resolution at every refresh change. Is this correct so far?

Now when I play a 4K UHD video though in Kodi, the resolution stays 1080 when passed to the TV. Is this to be expected?

Is this still a nightly feature in Jarvis builds. If so could you please give me a hint how to install the right build.

Thank you all so much for your kind help.

[beisat]

Hello

I'm new to using Kodi since I build my first HTPC 2 weeks ago - this issue is also still stopping me from enjoying it, maybe somebody could help?

Hardware setup:
Ouptut: PC (i5 6600k, GTX 970) connected via HDMI 2.0
AVR: Onkyo 646 (also HDMI 2.0)
TV: UE65JU6070 (also HDMI 2.0)

So naturally (as Windows 10 suggests), I have a 3840x2160 resolution on my desktop at 60hz and that works fine.

Kodi 16:
Kodi 16 also sets itself to 3840x2160 resolution, this also looks and runs fine for me in the GUI.
"Adjust display refresh rate" set to always
"Sync playback to display" is off

If I play a 1080p file, kodi upscales it and my tv receives a 3840x2160 image which looks bad.

So I read this thread, set Kodi to 1920x1080 and play a 1080p file: My tv receives a 1080p image, does the upscaling itself and image looks good -> perfect.

If I put my pc in hibernation, alt tab to desktop etc. and go back to kodi, my resolution is back at 3840x2160.

- How do I stop this behaviour of changing the resolution to fit the desktop?
Alternative: How do I tell kodi to playback my 1080p file without upscaling to 4k?

Thanks for your help a lot!

[xbmosx]

I played with this for another week and cannot get this to work, very disappointing. Beisat has the exact same problem although with another hardware setup, and I assume others must have gone through this as well (Linux machines on 4k TVs cannot be too uncommon nowadays) Does the fact that we don't get any answer mean there is no solution or that we asked a wrong question?

I'll happily post any logs if needed but as this is more of a howto question than a bug report I thought it wasn't necessary. mea culpa if I was wrong.
I read through this thread several times and actually it was only advised to run Kodi in 1080 resolution, but as far as I can see no advice on how to keep it in 1080 resolution.

Thanks in advance for any help!

[fritsch]

Which issues are you talking about?

The driver issue for hibernation and resume kodi cannot fix as it's an EDID / handshake / whatever issue. Workaround: Use and xorg.conf with a PreferedMode line -> it's an OS issue.

What kodi does is documented and clear:

Set your resolution to 1080p. Whenever a video is played your device is capable to switch up (!) (only up, never down), kodi will switch up.
If you set your resolution to 4k. Kodi will upscale the gui (bad quality, just bilinear). It will then upscale every 1080p movie to 4k, depending on the hw this might be looking good (Skylake, or nvidia > 720GT) or it will stutter as hell, also depending on the fps.

So which bug kodi shall fix?

[xbmosx]

Thanks for your reply fritsch.

As I said in my post this is not a bug report, but a question on how to achieve a desired behavior.

I do understand clearly the full second paragraph of your reply. This is exactly why I want to keep Kodi in 1080p mode. My problem is it doesn't stay in 1080p mode. Exactly as also Beirat explained Kodi takes all possible occasions (switching to windowed mode, changing input source on TV etc. -> I'm not even talking hibernation) to change back to the screens native resolution. I'm looking for a way to keep Kodi in 1080p mode without switching the whole OS to 1080p and hence loosing the ability to "switch up" in case a 4k movie is played.

I wasn't aware that this is supposed to be a driver issue. I will have a look at xorg.conf and PreferedMode. Will this make it possible to keep my OS in 4k and only Kodi in 1080p? Or what exactly am I trying to achieve with the xorg.conf PreferedMode settings?

Again thanks for your kind support!

[fritsch]

Ah! Now I get what you want. But yeah, that's not how an application should be designed.

When kodi is running on a desktop it behaves like an application. That means if your OS under the hood changes to 4k, kodi will also change. In kodi session (starting from lightdm) you can tell your xserver to run at 1080p PreferedMode, but this will also change "your desktop" resolution to 1080p.

I don't see what kodi could do as it acts like a desktop appliaction and not like an appliance. If you start kodi with kodi --standalone it will at least restore its 1080p setting, but yeah - not what you want.

[xbmosx]

OK, I think we are down to the problem now. So if I understand you correctly all the "switch up" talk is only true if you are running Kodi standalone (or any of the dedicated Kodi Linuxes, Elecs etc.) right?

[fritsch]

Yes. Kodi on a desktop is a desktop application, not allowed to switch anything. Though you can manually start kodi as: kodi --standalone so that it forces mode switching and stuff.

[xbmosx]

OK, I'm probably being a pain in the back here, but something is not entirely true about this last statement.

Let me explain: After I actually gave up on this topic I had to solve another resolution problem with my NUC. For unknown reasons Ubuntu always insisted to set a preferred resolution of 1080i 60Hz (interlaced - wtf) instead of the perfectly well available 1080p 50Hz (xrandr --verbose). So after some googling around I created a .xprofiles file and forced my system to the desired 1080p 50Hz resolution. Guess what. Not only is my system now working in the correct resolution also when I start a 4k file from within Kodi (which is also set to operate in 1080p) the "upswitching" to the movies native resolution works flawlessly. As soon as the movie stops the resolution switches back to 1080p. This is actually exactly the behavior I was expecting and hoping for. So it seems this little tweak solves all problems even if Kodi is running in application mode on top of Ubuntu desktop installation.