HDR not rendered correctly at fullscreen

Hey all. I have come across a problem with MPC-HC rendering HDR videos at fullscreen.

The luminance is only properly rendered if the player is on windowed mode, or if the seekbar is toggled at fullscreen mode.
To describe how the picture looks in words, the picture colour is, I guess, alright, for it does not look like it's HDR content being played in a SDR display where the colours are completely washed out. It's just the luminance that look duller and lacking the highlight it should have if not for toggling seekbar or to windowed mode.

I've tried various workarounds I can find online. I've tried between MPC VR and madVR to no success, even with fullscreen exclusive mode for both of them. I've also set the colour range to full (0-255) via NVIDIA Control Panel. "Use HDR" and "Stream HDR video" are turned on globally in Windows HD Color Settings.

With VLC Media Player on the other hand, the HDR only works fine for some videos, while the problem also persists for others in a similar manner.

I am not sure if this is a driver issue. I've gone past few updates since to no avail, and I do not remember the last driver where such problem does not occur.
This is not the first time facing such an issue, and a driver update has once fixed it for me. I'd rollback to the last known good driver just to get this HDR playback fully working like before, but I am not sure to what version should I reinstall to.

I am yet to try fresh installing my GPU drivers but I am not sure if it's even worth trying, and I am not sure what other workarounds or checks to try at this point.

Any advice is appreciated.

Videos:
Right clicking around at full screen: https://photos.app.goo.gl/8z7vi7wfG52ASxPN9
Toggling seekbar at full screen: https://photos.app.goo.gl/CfdJWTb3dij1rVRJ9

I'm using Acer VG271UP as my monitor, outputting from my desktop through Samsung HW-Q70R soundbar via HDMI 2.0.

Codec Tweak Tool | Log file | Generated at 2021-12-24 15:21:00

#####  System Information  #####

OS:           Windows 10 Enterprise (10.00.19044) (x64)
CPU name:     AMD Ryzen 7 5800X 8-Core Processor
CPU details:  3800 MHz | 16 core(s) | Family 25 Model 33 Stepping 0
Memory:       32704 MB
Screen size:  2560x1440 (32bits) (144Hz)
GPU:          NVIDIA GeForce RTX 3080
             VendorID: 10de, DeviceID: 2206
GPU memory:   10240 MB
GPU driver:   nvldumdx.dll (Version 30.0.14.9729) (12-15-2021) (NV 497.29)
Audio device: High Definition Audio Device
Audio driver: HdAudio.sys (Version 10.0.19041.264) (5-9-2020)

#####  K-Lite Codec Pack  #####

KLCP version: 16.6.8 (base 16.6.5)
KLCP type:    mega

Speaker conf: 7.1

MPC renderer: MPC VR
MPC subs:     ISR
MPC audio:    Internal Audio Renderer

#####  Decoder Settings #####

LAV Video:
H264=DXVA2CB HEVC=DXVA2CB VP9=DXVA2CB VC1=0 MPEG2=1 MPEG4=1 WMV3=0

LAV Audio:
MP3=1 AC3=B DTS=B DTSHD=B EAC3=B TRUEHD=B AAC=1 Vorbis=1 LPCM=1 WMA=0

#####  DirectShow Filters (32-bit)  #####

(A total of 76 filters, 0 shown, 76 hidden)

#####  DirectShow Filters (64-bit)  #####

(A total of 115 filters, 0 shown, 115 hidden)

#####  ICM Class Manager (32-bit)  #####

(A total of 3 filters, 0 shown, 3 hidden)

#####  ICM Class Manager (64-bit)  #####

(A total of 3 filters, 0 shown, 3 hidden)

#####  Default source filters (32-bit)  #####

(A total of 64 default source filters, 0 shown, 64 hidden)

#####  Default source filters (64-bit)  #####

(A total of 56 default source filters, 0 shown, 56 hidden)

#####  ACM and VFW Codecs (32-bit)  #####

Description:  RivaTuner Video Codec
ID:           VIDC.RTV1
File name:    c:\windows\syswow64\rtvcvfw32.dll

(A total of 21 codecs, 1 shown, 20 hidden)

#####  ACM and VFW Codecs (64-bit)  #####

Description:  RivaTuner Video Codec
ID:           VIDC.RTV1
File name:    c:\windows\system32\rtvcvfw64.dll

(A total of 19 codecs, 1 shown, 18 hidden)

Fullscreen video -> the HDR metadata from the video is used.
Anything else also on screen (seekbar/menu/other windows) -> default HDR metadata of Windows is used.

madVR exclusive fullscreen draws its own seekbar, which shouldn't have this issue.

Admin wrote:Fullscreen video -> the HDR metadata from the video is used.
Anything else also on screen (seekbar/menu/other windows) -> default HDR metadata of Windows is used.

madVR exclusive fullscreen draws its own seekbar, which shouldn't have this issue.

Yes that's true, about madVR's fullscreen exclusive seekbar. Still, the luminance is more muted than it has been.

I've tried fresh installing the 497.29 driver, to no avail. Thereafter I tried fresh installing between older drivers.
472.12 is the last driver without such an issue. The issue has started recurring from 496.13.

With the old NVIDIA driver, madVR could utilize the driver API to override the standard Windows behavior and keep HDR enabled in windowed mode. With that I mean the HDR properties from the video, not the semi-fake standard HDR mode of Windows. With newer driver it no longer allows that and it doesn't look like NVIDIA is ever going to fix/restore that behavior.

[I've edited my original post, the info below should now be correct!]

I was having the same issues with HDR windowed vs full screen mode. I came up with a solution for my HDR-capable monitor, haven't tested it on an HDR TV, but principle should work the same.

Software/hardware setup:
MPC-HC (v1.9.18)
madVR (v0.92.17)
Windows 10 (v21H2)
HDR-capable monitor (Dell S2721DGF, HDR400)
AMD Radeon video card with HDR support

Software settings:
MPC-HC->Options->Playback->Output->DirectShow Video->madVR [enabled]
madVR->devices->[HDR device]->properties->the native display bitdepth is: [10 bit (or higher)]
madVR->devices->[HDR device]->hdr->tone map HDR using pixel shaders->target peak nits: [enter your HDR device's peak nits], (NOTE: the peak nits value can be found under '[HDR device]->identification->desired max luminance)
madVR->devices->[HDR device]->hdr->tone map HDR using pixel shaders->tone mapping curve: [BT.2390]
madVR->devices->[HDR device]->hdr->output video in HDR format [enabled]
madVR->rendering->general settings->enable automatic fullscreen exclusive mode [enabled] (NOTE: can also be set to disabled, with same result)

Windows 10 settings:
Settings->System->Display->Use HDR [Set to On]

A few things are going on here to fix the windowed vs full screen mode issue.

1) Windowed mode
- Normally when you toggle to full screen mode, you are seeing an incorrect map of luminance values from your source HDR material (with different peak values between source and destination device), which is manifesting as "washed out" in full screen mode
- In windowed mode, Windows 10 is doing an approximate map of the peak nits values, aligned to your HDR device's peak nit value. However, in the case of an HDR1000 mastered movie (or higher) mapped to an HDR400 monitor, you'll notice the "bright" areas of the video are almost too bright, and it is clipping at the upper end of the luminance range.
- In full screen mode, madVR is passing the HDR info directly to your screen, including the meta data, without tone mapping of the luminance. In this example, HDR1000 content going to a HDR400 monitor, it causes it to look washed out, and not have proper peak luminance values.
- By using "tone map HDR using pixel shaders", you are fixing the issue in windowed and full screen mode by properly mapping the HDR1000 content luminance values to a narrower HDR400 luminance range (but still aligning peak values properly). Changing between "windowed full screen" vs "full screen" will now yield the correct result.

synth89 wrote:[I've edited my original post, the info below should now be correct!]

I was having the same issues with HDR windowed vs full screen mode. I came up with a solution for my HDR-capable monitor, haven't tested it on an HDR TV, but principle should work the same.

Software/hardware setup:
MPC-HC (v1.9.18)
madVR (v0.92.17)
Windows 10 (v21H2)
HDR-capable monitor (Dell S2721DGF, HDR400)
AMD Radeon video card with HDR support

Software settings:
MPC-HC->Options->Playback->Output->DirectShow Video->madVR [enabled]
madVR->devices->[HDR device]->properties->the native display bitdepth is: [10 bit (or higher)]
madVR->devices->[HDR device]->hdr->tone map HDR using pixel shaders->target peak nits: [enter your HDR device's peak nits], (NOTE: the peak nits value can be found under '[HDR device]->identification->desired max luminance)
madVR->devices->[HDR device]->hdr->tone map HDR using pixel shaders->tone mapping curve: [BT.2390]
madVR->devices->[HDR device]->hdr->output video in HDR format [enabled]
madVR->rendering->general settings->enable automatic fullscreen exclusive mode [enabled] (NOTE: can also be set to disabled, with same result)

Windows 10 settings:
Settings->System->Display->Use HDR [Set to On]

A few things are going on here to fix the windowed vs full screen mode issue.

1) Windowed mode
- Normally when you toggle to full screen mode, you are seeing an incorrect map of luminance values from your source HDR material (with different peak values between source and destination device), which is manifesting as "washed out" in full screen mode
- In windowed mode, Windows 10 is doing an approximate map of the peak nits values, aligned to your HDR device's peak nit value. However, in the case of an HDR1000 mastered movie (or higher) mapped to an HDR400 monitor, you'll notice the "bright" areas of the video are almost too bright, and it is clipping at the upper end of the luminance range.
- In full screen mode, madVR is passing the HDR info directly to your screen, including the meta data, without tone mapping of the luminance. In this example, HDR1000 content going to a HDR400 monitor, it causes it to look washed out, and not have proper peak luminance values.
- By using "tone map HDR using pixel shaders", you are fixing the issue in windowed and full screen mode by properly mapping the HDR1000 content luminance values to a narrower HDR400 luminance range (but still aligning peak values properly). Changing between "windowed full screen" vs "full screen" will now yield the correct result.

Apologies for the late reply but I can confirm this works. Optionally I could set it to clipping, but BT.2390 is arguably better. Cheers!