Is there a way to "preload" subtitles?

[andres87]

Ever since I started using Jellyfin a couple years ago I've been having the issue that subtitles (external .srt files) take a while to load. They can even take 5 minutes. I just pause the video at the start and wait for the "fetching aditional data" message to disappear. 

However I accidentally noticed that, if I open a video, pause it, then change my mind and go back to watch something else, when I do finally watch the first video it instantly loads the subtitle. It's like they are cached or something.

If so, is there any way to automatically cache the subtitles? Like a plugin that would do it in the middle of the night or something like that?

[kagetsu]

Fetching additional data only happens when the video you are playing has SRT subtitles and it's trying to extract them to the server's cache (which only needs to do it once) so it's there to play right away. On apple devices srt works wells I always pre-extract them and then using Flag editor I set all the subtitles embedded in the MKV file to NOT-default. Name the SRT file like this and it will play automatically:

Aliens 2.mkv
Aliens 2.en.default.srt

Do a refresh scan for new and updated files and it will include an entry for "Your subtitle" (External).

---

Example

[TheDreadPirate]

Try installing the "Subtitle extract" plugin. Then in the Dashboard's Scheduled Tasks run the extract subtitle job. This will pre-extract all subtitles that are embedded in your content so that this delay doesn't happen. But this could potentially use a lot of disk space on the volume where the jellyfin server data resides. PGS subs in particular are pretty large.

The reason for this delay is that the client you're on can't play embedded subtitles. So Jellyfin extracts the subtitle track on the fly to then send to the client as a separate stream. Depending on how fast your storage is and how big the file is, this could be half a second or several minutes. By using the subtitle extract plugin to pre-extract all embedded subtitles, you avoid this delay.