[jogal]

Yet Kodi reports it as 4K 10-bit 60hz RGB when its playing it.   How is that possible?

Because Kodi works internally with 10 bit RGB surfaces (it is what is physically inside the graphics card) and it does not matter if it is at 60 Hz or even more.

The limitation is only on the HDMI 2.0 connector. This is managed by the video driver and down-converts it to 8 bit (with dither) only for the output through that connector.

Both Intel and Nvidia drivers do the same: RGB 10bit to RGB 8bit (if Hz > 30 Hz). It never is converted to 4:2:0 or 4:2:2


If you buy an HDMI 2.1 graphics card (and HDMI 2.1 TV), Kodi it will still work internally exactly the same but then the output will be RGB 12bit at 60Hz or more.

[apachehaovk]

Yet Kodi reports it as 4K 10-bit 60hz RGB when its playing it.   How is that possible?

Because Kodi works internally with 10 bit RGB surfaces (it is what is physically inside the graphics card) and it does not matter if it is at 60 Hz or even more.

The limitation is only on the HDMI 2.0 connector. This is managed by the video driver and down-converts it to 8 bit (with dither) only for the output through that connector.

Both Intel and Nvidia drivers do the same: RGB 10bit to RGB 8bit (if Hz > 30 Hz). It never is converted to 4:2:0 or 4:2:2


If you buy an HDMI 2.1 graphics card (and HDMI 2.1 TV), Kodi it will still work internally exactly the same but then the output will be RGB 12bit at 60Hz or more.

Hey Jogal! First off thank you for all the hard work, you are awesome!

So something might be reported incorrectly maybe.

So from what I understand, if the entire chain is HDMI 2.0 and you play a 24hz regular UHD remux, Kodi will play it as RGB 10 bit HDR and it should look no different than playing the disk through a UHD player running at 4:2:0 correct?

But, when playing Gemini man which is the only 60fps UHD remux, the ctrl>shift>o build still reports it as playing 10-bit RGB.

Should it not be showing 8-bit RGB for HDMI 2.0 UHD remuxes that are 60hz?

Why does it still report 10-bit RGB 60hz HDR over HDMI 2.0?

Thanks!!!!!

[jogal]

Why does it still report 10-bit RGB 60hz HDR over HDMI 2.0?

Because Kodi works internally with 10 bit RGB surfaces always in a HDR mode. Kodi not knows if output port is HDMI 2.0 or 2.1...  10 bit to 8 bit is a conversion that the video driver does at a low level..... Kodi can't know.

Output means "output from Kodi"  (not input to TV)

Kodi outputs 10-bit RGB and Windows/graphics driver downconverts to 8-bit because HDMI 2.0 does not support it...... In the same way if there is an AVR in the middle of the chain it can convert the signal to another format...

If you ask it again, I'll say the same thing again

I'm also not interested in trying to explain or justify why 8bit RGB is better than 10bit 4:2:0. You have to believe that if Intel and Nvidia have decided to do it this way it is because it is better and there is a good reason.

[ciukacz]

Both Intel and Nvidia drivers do the same: RGB 10bit to RGB 8bit (if Hz > 30 Hz). It never is converted to 4:2:0 or 4:2:2

minor nitpick: that is true in a default state, after a clean driver install.
if you switch desktop temporarily to 4k23 12bpc rgb and switch desktop back to 4k60 8bpc rgb
the driver (or windows?) will remember that and next time you play a 4k23 movie kodi will switch to 12bpc rgb (last used bitdepth for that resolution/refresh rate combination).

tested on amd and nvidia win10 20h2, kodi 19 rc1.

[apachehaovk]

Both Intel and Nvidia drivers do the same: RGB 10bit to RGB 8bit (if Hz > 30 Hz). It never is converted to 4:2:0 or 4:2:2

minor nitpick: that is true in a default state, after a clean driver install.
if you switch desktop temporarily to 4k23 12bpc rgb and switch desktop back to 4k60 8bpc rgb
the driver (or windows?) will remember that and next time you play a 4k23 movie kodi will switch to 12bpc rgb (last used bitdepth for that resolution/refresh rate combination).

tested on amd and nvidia win10 20h2, kodi 19 rc1.

GOTCHA!!

Ok makes sense. So kodi is throwing out 10bit RGB no matter what when in HDR mode. Got it!

I guess I am just trying to find out what the hell the stupid LG oledCX is getting for a signal then. All it tells you is if HDR mode is active and if it’s rec2020.

When playing Gemini man or any other HDR movie it literally just says HDR Rec 2020 and never specifies if it’s 8 or 10 but at all!

Anyone with an LG CX know how to get more detailed video info?

Thanks Jogal!

[ciukacz]

I guess I am just trying to find out what the hell the stupid LG oledCX is getting for a signal then. All it tells you is if HDR mode is active and if it’s rec2020.

mash green button on the lg remote like 10 times, there is a hidden info screen very useful for that purpose.
tv just reports what it gets, the source is responsible for what is being sent.

[jogal]

Both Intel and Nvidia drivers do the same: RGB 10bit to RGB 8bit (if Hz > 30 Hz). It never is converted to 4:2:0 or 4:2:2

minor nitpick: that is true in a default state, after a clean driver install.
if you switch desktop temporarily to 4k23 12bpc rgb and switch desktop back to 4k60 8bpc rgb
the driver (or windows?) will remember that and next time you play a 4k23 movie kodi will switch to 12bpc rgb (last used bitdepth for that resolution/refresh rate combination).

tested on amd and nvidia win10 20h2, kodi 19 rc1.

I can't quite understand what you mean. I think this is imprecise or confusing....

if you switch desktop temporarily to 4k23 12bpc rgb and switch desktop back to 4k60 8bpc rgb

If you do not do this, the same thing happens:

Output is RGB 12-bit at 23,976 Hz  playing   4k23 (HDR) movie  because is default behavior of Intel and Nvidia.


As I said in previous posts.

For HDR content <= 30Hz

Kodi uses RGB 10-bit internally but graphics driver (Intel and Nvidia) forces RGB 12-bit output  (adds 2 bits padding)

For HDR content > 30Hz

Kodi uses RGB 10-bit internally but graphics driver (Intel and Nvidia) forces RGB 8-bit output (with dithering) because HDMI 2.0 bandwidth limitations. This not happens with HDMI 2.1 (12-bit always)

[ciukacz]

If you do not do this, the same thing happens:
Output is RGB 12-bit at 23,976 Hz  playing   4k23 (HDR) movie  because is default behavior of Intel and Nvidia.

my htpc is using amd apu so i am absolutely certain that it works this way on amd.
to test things out with nvidia (pascal) i once dragged my desktop to the living room and it was behaving the same as amd for me.
what mattered for me was that i could influence whether kodi hdr playback uses 8/10/12 bpc signal (alter default driver behavior).
that's why i am saying that this is just a default, you can change it's behavior if it's preferable.

doing some renovations atm and desktop is sitting unplugged now in living room so i may as well test it again with desktop 20h2 and new nvidia driver.

edit: jogal are you sure what signal your tv gets? on cx i have this nice debug screen. you have something similar on sony a9g?

[apachehaovk]

I guess I am just trying to find out what the hell the stupid LG oledCX is getting for a signal then. All it tells you is if HDR mode is active and if it’s rec2020.

mash green button on the lg remote like 10 times, there is a hidden info screen very useful for that purpose.
tv just reports what it gets, the source is responsible for what is being sent.

Yeah that’s the freesync info which says 8 bit nomatter what you feed into it. It’s a known LGcx bug. You can feed it any signal from any source including game consoles, UhD players, built in apps and it will always say 8bit nomatter what.

Just wish there was a way on this TV to just say real true 10 bit if it’s getting a 10bit signal, RGB or otherwise

[ciukacz]

Yeah that’s the freesync info which says 8 bit nomatter what you feed into it. It’s a known LGcx bug. You can feed it any signal from any source including game consoles, UhD players, built in apps and it will always say 8bit nomatter what.

Just wish there was a way on this TV to just say real true 10 bit if it’s getting a 10bit signal, RGB or otherwise

nope, that info screen is correct, i can make it display whatever format i want using the method described earlier
screenshots: https://forum.kodi.tv/showthread.php?tid...pid2989338

[jogal]

edit: jogal are you sure what signal your tv gets? on cx i have this nice debug screen. you have something similar on sony a9g?

I use AVR Denon OSD info or same info is accessible via HTTP server from LAN:



Since my setup is  PC (Intel NUC) --> AVR --> TV   

PC signal comes to AVR first.

"HDMI signal info" is current input signal from HDMIs inputs (PC)

and 

"HDMI monitor" is formats supported at output (TV)


I also have my desktop PC connected to another AVR input (currently Nvidia RTX 2060 SUPER) and by this I can easily verify that it behaves the same with Intel and Nvidia.

[scott967]

I use AVR Denon OSD info or same info is accessible via HTTP server from LAN:

Nice having access to a current Denon. I'm still using a 1080p 3311ci .

scott s.
.

[apachehaovk]

edit: jogal are you sure what signal your tv gets? on cx i have this nice debug screen. you have something similar on sony a9g?

I use AVR Denon OSD info or same info is accessible via HTTP server from LAN:



Since my setup is  PC (Intel NUC) --> AVR --> TV   

PC signal comes to AVR first.

"HDMI signal info" is current input signal from HDMIs inputs (PC)

and 

"HDMI monitor" is formats supported at output (TV)


I also have my desktop PC connected to another AVR input (currently Nvidia RTX 2060 SUPER) and by this I can easily verify that it behaves the same with Intel and Nvidia.

OK! So on my Denon I was able to verify on that screen that when playing a 24hz remux UHD it says 12 bit rec 2020!

And as expected due to bandwidth limitations of HDMI 2.0, 60fps Gemini man reports HDR rec2020 BUT it’s at 8bit, as expected.

Wondering if anyone has an HDMI 2.1 chain to see if Gemini man does 12bit?

ALSO!  Installing the final Kodi 19 Matix fixed the LG oled reporting 8bit only.  Now it shows 12-bit.  I rolled back to RC1 and it only shows 8bit.  Something changed with HDR between RC1 and final.  Either way, I am happy!

Thanks Jogal! You are a master at this!

[apachehaovk]

Yeah that’s the freesync info which says 8 bit nomatter what you feed into it. It’s a known LGcx bug. You can feed it any signal from any source including game consoles, UhD players, built in apps and it will always say 8bit nomatter what.

Just wish there was a way on this TV to just say real true 10 bit if it’s getting a 10bit signal, RGB or otherwise

nope, that info screen is correct, i can make it display whatever format i want using the method described earlier
screenshots: https://forum.kodi.tv/showthread.php?tid...pid2989338

Must be an AMD thing.  Nvidia seems to just never output 10 or 12 bit color ever no matter what settings

[_novalis]

Hi,
I am posting this here again because it still is a problem and maybe gets more attention than in my dedicated thread.
the issue:
If I play a HDR video Kodi does its HDR switching only after fullscreen toggle.
The TV gets the HDR signal but Kodi only after I toggle from fullscreen to windowed to fullscreen.
Before the toggle Windows is in hdr mode but Kodi not.
I have tried both settings 'use fullscreenwindow' on and off.
I have also tried every other recommended setting. I think.
It helps if I start the video in windowed mode and then toggle to fullscreen.
The problem hasn't changed since I swapped from Fandangos Version to Kodi Master months ago and persists until today having the released final v19 installed. The problem was not present in Fandangos version and appeared first with the use of Kodi Matrix Master.
AMD Adrenalin is up to date.


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