Transcoding in Kodi

[tmsrxzar]

I have used the linuxserver/jellyfin docker image, I am now building a new database with the jellyfin/jellyfin docker image.
Just to be sure that is not the issue … so that will take quite some time to get back in business and test again.

I have tried multiple files, also with only english subs and 1080p video.

That many subtitles is normally also no issue for Kodi and that uses quite an old ffmpeg from what I know.
Kodi 21 will make a jump to version 6 instead of 4 from what I heard.

no, you're talking about being able to play the file
what i'm pointing out is that jellyfin server is extracting each subtitle track to serve it to kodi "when transcoding" and perhaps the process of "extracting" 24 subtitles is taking too long and causing errors

[Theetjuh]

True, I was reacting about if ffmpeg can handle all those subtitles, it can … but indeed the transcoding part I have no clue about.

[mcarlton00]

The errors you're seeing in the logs about subtitles, while in the kodi logs, are actually happening on the server. In this case, client means basically nothing. It's requesting data from the server and the server is either taking too long or having an error during the processing. It's possible there's a race condition of some kind when you get to large numbers of subs, none of my files have that many.

There's also a distinct possibility that this is all a (semi) pointless exercise. Generally transcoding is only used when the client can't play the original file. In this case it sounds like you're playing 4k content on a 1080p tv and just want to receive a 1080p source instead, but iirc kodi does scaling to handle that automatically. So if there's not a playback issue happening with direct play, there's really not any reason to request a transcode. There does still seem to be a bug or limitation of some sort, but possibly not actually relevant to your use case. Unless I misunderstood and the direct play is actually having issues.

[Theetjuh]

It’s more the HDR tone mapping to SDR that is needed for the 1080p tv, that’s at least why I wanted the transcoding to work.

[mcarlton00]

Ah, now things make more sense. I was thinking it was purely resolution based. I wonder if that's the key detail, as I don't have any hdr content that requires tonemapping. Would explain why I can't replicate it on any of my test systems. Do you have any non-hdr content to test transcoding with? And/or things with less subtitle tracks? Still have multiple variables so we've gotta do some more experimenting to narrow down where the issue actually lies.

[Theetjuh]

I got it working without the reverse proxy it seems, but it has issues with some Dolby Vision files it seems.
So it doesn’t transcode some, but others with HDR10 it does.

Will try some other stuff later, http reverse proxy instead of https and check the amount of subs on those files with transcoding issues.