Jellyfin won't render .ASS subtitles

[TheDreadPirate]

The one that works has font attachments. The one that doesn't work does not have font attachments. So my theory appears to hold some water.

Once I get home, in 4-5 hours, I will test again on unRAID.

[rizill]

okay brilliant

[TheDreadPirate]

Confirmed. If your video with ASS subs doesn't include fonts attached unRAID will not render the ASS subs using system fonts. Now to figure out what to do about it.

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Interesting. The same happens on my test instance in Docker on Ubuntu.

[rizill]

yeah.. hoping there is an easy ish way to resolve this

[TheDreadPirate]

Another interesting development. My main Jellyfin instance, also in Docker on Ubuntu, works fine. Same version as my test instance on Ubuntu, same host even. Same version as my test instance on unRAID.

More investigation......

[rizill]

Hi again, did you make any progress on the matter? I discovered that direct playing from the jellyfin desktop client does seem to show working .ass subtitles, however transcoding makes them not appear at all as described earlier.

[TheDreadPirate]

Unfortunately, no. I haven't been able to replicate, but my system is not identical to yours. This could be some sort of Nvidia driver bug. Are you using the latest available for unRAID?

[dje33]

Hello, I have the same problem and i have carried out some tests because it worked before.
With Jellyfin 10.10.3, I have certain media that does not display .ASS
With Jellyfin 10.9.11 the .ASS subtitles are displayed on all media.

I use docker jellyfin/jellyfin or jellyfin/jellyfin:10.9

Ubuntu 24.04LTS on a intel N100 vith hardware accélération.

How can I help you resolve this bug?

[TheDreadPirate]

Does the problem ASS subs not have any font attachments in the file?

[dje33]

Font attachments in the file : OK
No Font attachments in the file : OK in 10.9.11 / NOK in 10.10.3

.ass with no font attachments

Code:

[Script Info]
ScriptType: v4.00+
Collisions: Normal
PlayResX: 1920
PlayResY: 1080
Timer: 100.0
WrapStyle: 0

[V4+ Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
Style: Default,sans-serif,71,&H00FFFFFF,&H00FFFFFF,&H000F0F0F,&H000F0F0F,0,0,0,0,100,100,0,0.00,1,2,3,2,20,20,20,0

[Events]
Format: Layer, Start, End, Style, Actor, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:01.27,0:00:03.89,Default,,0,0,0,,Pourquoi est-on ici ?
Dialogue: 0,0:00:03.98,0:00:05.94,Default,,0,0,0,,Pour sortir.\NEtre ici, c'est sortir.