scRGB output clamped to sRGB color gamut when SDR ACM is enabled

[Headcrabed]

mpv Information

mpv v0.41.0-566-g0a0c63d3e Copyright © 2000-2026 mpv/MPlayer/mplayer2 projects
 built on Apr 29 2026 10:10:17
libplacebo version: v7.363.0 (v7.360.0-33-g27aa71a-dirty)
FFmpeg version: N-124254-g397c7c752
FFmpeg library versions:
   libavcodec      62.30.100
   libavdevice     62.4.100
   libavfilter     11.17.100
   libavformat     62.13.102
   libavutil       60.30.100
   libswresample   6.4.100
   libswscale      9.7.100

Other Information

- Windows version: 11 25H2
- GPU model, driver and version: AMD Radeon RX 7800XT (Driver 26.3.1)
- Source of mpv: github.com/zhongfly/mpv-winbuild/
- Latest known working version: N/A
- Issue started after the following happened: N/A

Reproduction Steps

mpv config:

vo=gpu-next
gpu-api=auto
hwdec=auto
hwdec-codecs=all
#for enabling d3d11 scRGB
d3d11-output-format=rgba16f
target-peak=80

treat-srgb-as-power22=input
sdr-adjust-gamma=yes
target-contrast=inf

Download any sample files from https://webkit.org/blog-files/color-gamut/
Enable WIndows ACM and Use a Chromium-based browser, go chrome://flags , set Force color profile to scRGB linear and restart browser. Compare how the sample image looks on mpv and browser(Windows image viewer produces same result as browser).

Expected Behavior

All software produces the same behavior.

Actual Behavior

The image looks different when image is sRGB, but that's due to treat-srgb-as-power22=input. Set treat-srgb-as-power22=no would make sRGB image looks the same.

Log File

log.log

Sample Files

https://webkit.org/blog-files/color-gamut/

I carefully read all instruction and confirm that I did the following:

• I tested and confirmed that the issue exists with the latest release version or newer.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

[kasper93]

Windows compositor (DWM) clamps everything to sRGB in SDR mode, both gamut and extended hdr range. This is what I also have seen. Our scRGB output is correct as can be evident by it working when HDR is enabled in Windows.

[Headcrabed]

Windows compositor (DWM) clamps everything to sRGB in SDR mode, both gamut and extended hdr range. This is what I also have seen. Our scRGB output is correct as can be evident by it working when HDR is enabled in Windows.

No, edge and win photo viewer are not clamped.

[kasper93]

You can see it in stats, you image is gamut mapped to your screen. You probably can set some big --target-gamut to disable gamut mapping. But not sure why you prefer clipping.

[llyyr]

No, edge and win photo viewer are not clamped.

Can you try renaming mpv binary to Edge.exe or whatever Edge's binary is called?

[Headcrabed]

No, edge and win photo viewer are not clamped.

Can you try renaming mpv binary to Edge.exe or whatever Edge's binary is called?

No difference.

[kasumikira]

I can confirm this issue presents. A workaround described in this page is enabling the display ICC compatibility helper, but the proper fix is described here.

[ikas-mc]

It would be even better if mpv could get the enabled status of WideColorGamut.

https://learn.microsoft.com/en-us/windows/win32/api/windows.graphics.display.interop/nf-windows-graphics-display-interop-idisplayinformationstaticsinterop-getforwindow

https://learn.microsoft.com/en-us/windows/win32/api/wingdi/ne-wingdi-displayconfig_device_info_type
DISPLAYCONFIG_DEVICE_INFO_GET_ADVANCED_COLOR_INFO_2

[dyphire]

It would be even better if mpv could get the enabled status of WideColorGamut.

https://learn.microsoft.com/en-us/windows/win32/api/windows.graphics.display.interop/nf-windows-graphics-display-interop-idisplayinformationstaticsinterop-getforwindow

https://learn.microsoft.com/en-us/windows/win32/api/wingdi/ne-wingdi-displayconfig_device_info_type DISPLAYCONFIG_DEVICE_INFO_GET_ADVANCED_COLOR_INFO_2

In fact, this is not reliable, and the system will still report as a wide color gamut when the Windows ACM is opened on the srgb color gamut display. Stupid Microsoft.

[ikas-mc]

It would be even better if mpv could get the enabled status of WideColorGamut.

https://learn.microsoft.com/en-us/windows/win32/api/windows.graphics.display.interop/nf-windows-graphics-display-interop-idisplayinformationstaticsinterop-getforwindow

https://learn.microsoft.com/en-us/windows/win32/api/wingdi/ne-wingdi-displayconfig_device_info_type DISPLAYCONFIG_DEVICE_INFO_GET_ADVANCED_COLOR_INFO_2

In fact, this is not reliable, and the system will still report as a wide color gamut when the Windows ACM is opened on the srgb color gamut display. Stupid Microsoft.

My srgb monitor didn't get such an error result. and my other monitor can report correctly in standard mode (off hdr). If the user's monitor does not support it, it should not be turned on.

ACM cannot be turned on on my P2145q at all.

and how to properly handle the monitor and the ACM is another topic which has nothing to do with the current problem. just like HDR monitor

[Headcrabed]

It would be even better if mpv could get the enabled status of WideColorGamut.
https://learn.microsoft.com/en-us/windows/win32/api/windows.graphics.display.interop/nf-windows-graphics-display-interop-idisplayinformationstaticsinterop-getforwindow
https://learn.microsoft.com/en-us/windows/win32/api/wingdi/ne-wingdi-displayconfig_device_info_type DISPLAYCONFIG_DEVICE_INFO_GET_ADVANCED_COLOR_INFO_2

In fact, this is not reliable, and the system will still report as a wide color gamut when the Windows ACM is opened on the srgb color gamut display. Stupid Microsoft.

@dyphire @ikas-mc This actually reports ACM and HDR's enablement status than whether the monitor is wide-gamut. Blender guys found the actual usage for this by looking into WinRT: https://projects.blender.org/blender/blender/src/commit/f49b3dabf1da3489e58df2970d178f3f02f3a192/intern/ghost/intern/GHOST_WindowWin32.cc#L1331

Also, I think windows wouldn't show ACM option if the monitor isn't wide gamut. How could that become possible?

[Headcrabed]

I can confirm this issue presents. A workaround described in this page is enabling the display ICC compatibility helper, but the proper fix is described here.

@kasumikira That compatibility helper isn't a workaround at all.... We are already outputting scRGB, and this have no relationship about that helper. That helper allows passthrough software window directly without color space conversion.

[dyphire]

@dyphire @ikas-mc This actually reports ACM and HDR's enablement status than whether the monitor is wide-gamut. Blender guys found the actual usage for this by looking into WinRT: https://projects.blender.org/blender/blender/src/commit/f49b3dabf1da3489e58df2970d178f3f02f3a192/intern/ghost/intern/GHOST_WindowWin32.cc#L1331

Also, I think windows wouldn't show ACM option if the monitor isn't wide gamut. How could that become possible?

Let me clarify: What I means is Windows still provides ACM when the wide color gamut display uses srgb color gamut instead of wide color gamut in the display settings. In this case, if ACM is enabled, the entire display and system report will be wrong. Although I agree that users should not do this, it is still a stupid system behavior.

[Headcrabed]

Let me clarify: What I means is Windows still provides ACM when the wide color gamut display uses srgb color gamut instead of wide color gamut in the display settings. In this case, if ACM is enabled, the entire display and system report will be wrong. Although I agree that users should not do this, it is still a stupid system behavior.

@dyphire That's your monitor's fault, not Windows. Windows detect whether the monitor is wide-gamut by reading it's EDID's color space information. If your monitor doesn't change EDID-provided colorspace info when changing monitor's color gamut, you should set correct ICC file in Windows' color settings in this case.