HDR video appears dull and incorrect when unpaused or switched to fullscreen

[tofu-dreg]

mpv Information

mpv v0.39.0-dev-ga8f5beb5a Copyright © 2000-2025 mpv/MPlayer/mplayer2 projects
 built on Mar 14 2025 16:09:38
libplacebo version: v7.350.0
FFmpeg version: 7d1c1d5
FFmpeg library versions:
   libavcodec      61.19.101
   libavdevice     61.3.100
   libavfilter     10.4.100
   libavformat     61.7.100
   libavutil       59.39.100
   libswresample   5.3.100
   libswscale      8.3.100

Other Information

- Windows version: Microsoft Windows [Version 10.0.26100.3476] (Windows 11)
- GPU model, driver and version: Nvidia 4070 Ti,  driver ver. 572.70
- Source of mpv: first party builds (mpv-x86_64-windows-msvc) -- however shinchiro and zhongify builds exhibit same issue
- Latest known working version: Unknown (I only acquired an OLED monitor yesterday)
- Issue started after the following happened: Unknown (same as above)

Reproduction Steps

Opening the HDR video in mpv and pausing it, then unpausing it and/or switching to fullscreen

Expected Behavior

mpv plays HDR video with correct looking brightness and TRC

Actual Behavior

When playing HDR videos via Chrome (whether via Youtube or playing the downloaded webms in Chrome directly), the video appears correct with very bright highlights and correct looking EOTF with proper detail visibility, whether paused or unpaused or windowed/fullscreened.

In mpv, the video only appears 'correct' (i.e. matching Chrome) while paused and windowed; upon unpausing the video or switching to fullscreen, it becomes duller looking with less highlight brightness, less vivid colours and some kind of wrong looking EOTF that makes detail visibility worse. Additionally, while windowed and paused, the video will momentarily flash to the duller look while the "Screenshot: filename.etc" message is visible in the top left corner, and will also momentarily flash to the duller look when moving the mouse away from the focused window.

Additional information:

• This issue occurs across multiple HDR videos that I've tested, not just the one used in this output.txt
• I tried adjusting d3d11-exclusive-fullscreen=yes/no to no avail
• I tried gpu-api=vulkan to no avail
• I tried --no-config to see if I could locate the cause via reintroducing my config options one by one, but the issue occurs in some form or another even with no config at all, albeit exhibiting itself differently, but always exhibiting some noticeable difference in gamma/visible detail between windowed and fullscreen modes or paused/unpaused
• I tried disabling fullscreen optimisations on mpv.exe
• I tried disabling G-sync in nvidia control panel and VRR in monitor OSD
• I tried disabling Nvidia overlay via NVApp
• I tried setting icc-profile-auto=yes/no
• I tried searching for similar issues and found a few earlier github threads relating to windowed-fullscreen differences, but nothing that pertained exactly to my issue or could solve it

Screenshots: I was unable to get screenshots to work in a way where they usefully showed any difference. With screenshot-format=avif, the screenshots produced were entirely red and looked identical to each other anyway. I suspect tonemapped SDR screenshots would also fail to capture the observed difference, but if anyone knows how to configure the screenshot options in such a way that they can produce useful information I'll be happy to give it a try.

OBS recording: I tried taking an OBS recording with HDR settings to see if it could capture the difference, but strangely the issue did not show up in the recording, with the sample video appearing correct at all times in the recording when moused over and toggled between windowed and fullscreen and/or paused-unpaused (I used Chrome to view the OBS recording)

Log File

output.txt

Sample Files

No response

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

• I tested with the latest mpv version to validate that the issue is not already fixed.
• 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.