From what you described, it sounds like the main problem was the tone mapping path rather than Jellyfin itself. The FFmpeg error 237 pointing toward the OpenCL/tone mapping chain makes sense, especially if everything started working properly after fixing the OpenCL side.
I think the important thing now is not to keep changing too many settings while it is working. Jellyfin transcoding can get messy very quickly if several things are changed at once.
James’ setup is also a good reference point because he has tested a lot of HDR and DoVi files successfully, so it’s useful to compare against a known working setup.
Good result in the end. Glad you pushed through it.
I didn’t mean to impose my tastes on you,
I just wanted to show you that what I did actually works.
That’s actually why I displayed the video data on the screen.
