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[bogdanbz]

I compared JRVR with madVR on my TV, while using Windows HDR, and I'm seeing a different behavior between the two:
- all gray bars above 1000 nits can't be distinguished when using madVR
- gray bars all the way up to 10000 nits can be distinguished when using JRVR, even though HDR to HDR tone mapping is disabled, and DirectX reports 1000 nits as the max display luminance.

The TV is a S95C which is able to display up to 1300 nits, but Windows reports only 1000 nits as the max luminance (because the EDID TV info does not report any min/max/frame luminance data in its static HDR metadata). "static" HDR tone mapping is enabled on the TV.

JRVR options: Screen Gamut = Auto, Gama processing = Disabled, Calibration method = disabled, Upscaling = Jinc, Chroma upscaling = FastBicubic, Scale in sigmoidal light = enabled, Enable anti-ringing filter = disabled, SuperRes = disabled, Advanced upscaling = disabled

The gray ramps are those in this m2ts file, starting at 3:19. The file is from the Zombieland UHD disc (Sony had these on their discs, and you could view them by using a special code on the remote while in the disc menu): https://files.catbox.moe/q6uv3y.m2ts

[Hendrik]

You can look at the OSD for rendering steps. It does not run any tone mapping in HDR pass-through. Assuming of course you turned pass-through on, which is off by default, and you did not point it out specifically in your options.

Wouldnt you want your TV to tonemap so all is visible? If anything, this sounds like the desirable result over madVR.

Windows can actually take HDR Screenshots in JXR format, although analyzing them is a matter of tool support then (Using Win+G in the Game Bar, screenshots in HDR mode take there will save as .jxr as well as .png)
"HDR + WCG Image Viewer" reports the estimated max brightness of my JXR screenshot at 9849, close enough to the full 10k for me, considering I don't know how good that tool is, and at the high brightness levels even small errors result in high nit differences, and JPEG-XR support seems very bad over the ecosystem of tools I use.

Also when testing pass-through always go full-screen,  it doesnt pass metadata in windowed mode (a limitation of the swapchain, I assume. Windows just doesn't care about the data unless its fullscreen)

Your sample certainly looks overblown on my desktop HDR screen, but that one doesn't have super tone mapping. Looks fine with HDR to HDR tone mapping on.

[bogdanbz]

I think I understand now what's going on from your reply. JRVR is always calling SetHDRMetadata when displaying HDR content.

Unfortunately this makes the TV change the tone mapping curve from the default one, as we found out in the owner's thread on avsforum. That's why I get to see all the bars up to 10000 nits.

Not all tone mapping curves this TV has built in are any good, so it would be really nice to be able to avoid sending any HDR metadata at all. This is what Microsoft recommends applications do anyway, in the big warning at the beginning of the documentation of this method call: https://learn.microsoft.com/en-us/windows/win32/api/dxgi1_5/nf-dxgi1_5-idxgiswapchain4-sethdrmetadata

I would like to request a checkbox in the JRVR settings to disable the sending of HDR metadata to the display (to not make this call, in other words). madVR has such a checkbox on the device hdr settings page.

JRVR is indeed enabled to pasthough HDR to the display, and MC is configured to launch playback in fullscreen.

[Hendrik]

You can use HDR to HDR tone mapping to influence what metadata is being send, and at the same time ensure the image matches that data. Which would match the recommended course of action you quoted. Set HDR to HDR tone mapping to your screens capability and it tone maps to your screens capability, as the article wants you to do.
If we don't specify any metadata, then Windows will just send some default. You really rather want to control that, especially since as you say your TV does not actually report its capability to Windows, so that default cannot be correct.

You really don't want the ability to send a 10k nits signal and then not have anything tone map that. Because that image would just end up badly clipped.

[bogdanbz]

That's exactly what I want though.

I want the default tone mapping curve of the TV (which it uses until something sends it HDR static metadata) to be used when I configure the TV to use "static" tone mapping in its settings. I always have the ability to change that setting to the "active" tone mapping.

Another issue with having JRVR sending HDR metadata is that the TV keeps using the tone mapping curve even after JRVR was closed. So any of the modern games with HDR support you start afterwards that don't send HDR metadata and that you calibrated their max luminance, will now show dimmer than you want because the TV is stuck using a 10000 nits tone map curve.

And it also means the TV HDR calibration you painstakingly made becomes useless after you use MC with JRVR.

This is why it's important to be able to not send HDR metadata. It's affecting all other applications you start after playing some HDR content in MC.

[bogdanbz]

Hello again!

Any chance to have the checkbox to disable calling SetHDRMetadata by JRVR in the next MC release?

So that the tone mapping curve on the TV is not affected permanently after playing HDR content in MC with JRVR for applications that follow Microsoft's recommendation of not calling SetHDRMetadata.

[Hendrik]

Probably not, thats not an option exposed through libplacebo which actually manages the swapchain, and also the kind of special-case secret sauce option I really want to avoid in JRVR, as it just causes confusion, and would find use by probably one user.

Also, I cannot reproduce the behavior you describe. Looking at a HDMI metadata analyser, Windows sends different metadata as soon as fullscreen is closed, returning to its normal profile as calibrated with the Windows HDR Calibration tool.

[bogdanbz]

Interesting. Does it do the same if there is no Windows HDR calibration? (when I'm referring to calibrating the TV, I'm referring to calibrating the TV using its controls and not by using the HDR calibration screen in Windows, which doesn't exist on Win10).

Related to that, is it possible to have the max luminance field editable in the JRVR options? Instead of using the value reported by DirectX, to use the value I type there. This way I could type the actual value of 1300 nits instead of the default one of 1000 nits that gets used when the TV doesn't report maxCLL in its EDID.

Another question related to this is: is this max HDR luminance value that JRVR reports used in some way by the DV to HDR10 or HDR10+ to HDR10 mapping?

[Hendrik]

The value shown in the control panel is informational only. HDR is generally not processed if HDR output is enabled, unless you enable HDR to HDR tonemapping, in which case it uses the value you enter there - which you could make the 1300.