@atc98092 wrote:But one thing I did notice is that it won't display the text captions that are embedded in the video. These were all recorded OTA TV broadcasts, and they all have EIA-608 captions. RMP will display these captions, but for some reason Jellyfin doesn't see them.
This is interesting. I didn't know Roku devices had that capability. I've been using a program I found a while back to turn the captions from recorded broadcasts into an SRT file. I may have to look into this. 🤔
Yes, Roku devices will display text based captions. This includes external files, such as .SRT, or embedded in the video like OTA broadcasts. Of course, very few commercial DVDs or Blu Rays used that form. They use image based captions, which no Roku can display. A media server can bu-rn those captions into the video feed, but that requires video transcoding and it's preferable to use a more powerful computer to handle the load. Almost all of my OTA recordings have text based EIA-608 captions, but I'm not aware of any commercial disc I've ever purchased that has anything but PGS or VOBSUB, both image based.
I do remember something about the eia-608/708 subtitles being an issue on github discussions. I think it was a container issue and web-client issue. The Jellyfin Codec page says they are supported https://jellyfin.org/docs/general/clients/codec-support/, and I remember having to enable "Allow All" under the "Disable different types of embedded subtitles" setting under the Libraries setting. (dashboard/libraries)
If you use Jellyfin through the channel/app, or even the web server (127.0.0.1:8096), the 608 subtitles aren't detected, but if using DLNA (the Roku Media Player), then they are detected.
Some users reported resolving the issue, but I never got it to work. (other than using RMP).
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I had given up on that and just extracted the 608 subtitles using ffmpeg and either converted them to srt or just downloaded vtt/srt and placed them into the mkv container so they were visible to both the Jellyfin channel/app and Roku Media Player.