Tone Mapping issues

[s0larsoul]

Hi! I've got jellyfin running on my server in local network. It's configured with both tone mapping options, VPP and just tonemapping. I'm using the official Windows desktop client, RTX 3090 as GPU. The screen isn't capable of HDR. I'm using mpv.conf in AppData, but only for subtitles styling. Some of my movies are in HDR, so tonemapping has to happen somewhere. However, I can't find where it does happen. In the playback info, I get Direct Play and SDR video, mpv video player. The video is definitely tonemapped. The weirdness of all of it is when I disable tonemapping in the dashboard, on the server literally nothing changes, the playback info is the same, the video is still tonemapped. And to add to this, the stream quality is worse when I compare it to MPC with Madvr (no fancy upscalers there, just default cubic), this is when I began to investigate. Transcoding on the server side is definitely not happening, since it's busy doing encoding of the other movie in 4k HDR, and won't be capable of instantenous playback and seek. Any ideas what's going on, where to dig?

[TheDreadPirate]

It is probably being tone mapped on the client in MPV. Open task manager and look for GPU decode/encode utilization.

[s0larsoul]

Yeah, looks like it, didn't expect it to be marked as SDR in playback info in Jellyfin. So, to confirm and change the behaviour - how would one disable tonemapping or change its settings?

[TheDreadPirate]

Can you share the media info of the video? In the Jellyfin UI go to the video and click on the "..." context menu and click "Media Info". There is a copy button at the top of the window that pops up.

[s0larsoul]

Damn, you are right. I forgot to transfer HDR metadata while re-encoding movies.

[s0larsoul]

Can you share the media info of the video?  In the Jellyfin UI go to the video and click on the "..." context menu and click "Media Info".  There is a copy button at the top of the window that pops up.

Coming back after fixing metadata and additionally trying the source files. Here is an example of metadata:

Code:

Video
Title: 4K HEVC HDR
Codec: HEVC
AVC: No
Profile: Main 10
Level: 153
Resolution: 3840x2160
Aspect ratio: 16:9
Anamorphic: No
Interlaced: No
Framerate: 23.976025
Bitrate: 29254 kbps
Bit depth: 10 bit
Video range: HDR
Video range type: HDR10
Color space: bt2020nc
Color transfer: smpte2084
Color primaries: bt2020
Pixel format: yuv420p10le
Ref frames: 1

I'm at Win11, Jellyfin Media Player (Desktop). There is still no HDR output, just the tonemapped video, whether HDR is enabled in Windows settings or not. Now I know I can tune tonemapping via mpv.conf locally, but I would like to get HDR metadata sent to display. MPC with MadVR and mpv-shim works correctly. I've tried target-colorspace-hint=yes and vo=gpu-next in the config. With the latter video plays back correctly, but weirdly in a separate window. Am I missing something, or HDR direct playback is currently impossible in Desktop client natively, without mpv-shim or other third-party shenanigans? Is Desktop client in work at all, or should I not expect any updates (half a year already) and move to some other solution?

[TheDreadPirate]

Jellyfin Media Player cannot currently output HDR. It is a limitation of the rendering pipeline in JMP, which it QT5 based.

JMP is being reworked to use QT6. But that is a big endeavor with no ETA.

MPV Shim is your best option for actual HDR on PC with Jellyfin.

[gnattu]

> JMP is being reworked to use QT6. But that is a big endeavor with no ETA.

It is not a QT issue for HDR. It is mpv itself. The maintainer of mpv has little to no interest in enhancing the libmpv's renderer api so that the application using this api (like JMP) can use the more modern gpu-next vo capability. You can never use the gpu-next with current libmpv's renderer API, no matter how.