How to insert SPU subtitle

[Stanoje]

Hello,
I've been searching out for an answer of the issue, but haven't found any yet.

So, I have downloaded a movie that has an SPU subtitle inserted in it (Codec: DVD Subtitles SPU).
It is in a certain font and size that is impossible to change and remove from the subtitles list but still could be turned off/on so it certanly isn't "hardcored/encoded" in a video as soon as I can manually turn it off and display another subtitle (Codec: Text subtitles with various tags SUBT).
I know that those are different formats, that SPU stands for Sub-Picture Unit so my question would be is it possible for me to convert an SRT subtitle to SPU and display it on video without encoding it?

Thanks in advance!

[Hitchhiker]

https://forum.videolan.org/viewtopic.php?t=67727