HDR content not directly playing on capable LG TV

[RJK]

Hi,

Since last year, I am having issues playing HDR content on my OLED55C7V-Z LG TV from 2017. This all started around July 1st of 2024 when I updated my Jellyfin server and/or updated my TV's operating system. I can't remember exactly what I did at the time. I was able to play HDR content before with Jelyyfin, but after July 1st, it was not possible anymore. TV specs: https://www.lg.com/uk/tvs-soundbars/smar...oled55c7v/

My server is an ancient pc, around 15 years old with a Intel® Celeron® CPU G530 @ 2.40GHz processor. My media library is set up in such a way that transcoding is not required. All content should be able to be directly played on my TV. The strange thing is that I have installed Emby on the same server and it can directly play 4K HDR content without any problems. Server specs: https://pastebin.com/VVik143k

I will provide two examples of TV shows. Episodes Anjin and Seventh Man. Both can be played directly with Emby, both need transcoding with Jellyfin. 

Logs:
Jellyfin: https://pastebin.com/2K7utzGN
Anjin: https://pastebin.com/5JjfBCSg
Seventh Man: https://pastebin.com/XskvBV7t
Emby: https://pastebin.com/beua02b6

Things I have tried:
-          Setting up media server from scratch
-          Restore factory settings on TV
-          Change internet quality to different settings on my TV
-          Toggle “Prefer fMP4-HLS Media Container” on and off

I just can't figure out what causes Jellyfin to not be able to play HDR content directly. I have another LG TV, a 43NANO793NE and it can play HDR content with Jellyfin. Any ideas?

[RJK]

It feels like Jellyfin can't activate HDR for some reason

[anteus]

Looks like it could be due to DOVI. I had to remux from mkv to mp4 before but seems to be working fine on 10.11 RC8 when I turn off allow transcoding for the user.

I had it working without remuxing on 10.10 through DLNA as well. The server shows up under the Input button when it's running. Note that the DLNA plugin isn't available yet on 10.11 RC8.