[Cin] Offtop: "Spp2Pgs - Converts general subtitles to HDMV PG streams"

[Andrew Randrianasulu]

So, I was doing another pass at 'what exactly can encode those PGS streams?' 
and found this little project:

https://github.com/subelf/Spp2Pgs

--desc----

Spp2Pgs

Converts general subtitles to HDMV PG streams.
In other words, converts .ass files to .sup files.

The project generates a command line application and a CLR dll file.
Core of them is a static library, libspp2pgs.

An external dll, xy-VSSppf, is introduced to deal with subtitle files.
It's based on a forked version of xy-VSFilter, rendering and providing subtitles in a more easy way.

Here is a breif description for all the four parts.
Spp2Pgs*.exe

An executable converts subtitles to .sup files.
Usage:
Spp2Pgs -i "X:\Saya1011con.ass" -s 1080 -r 23 "X:\Saya1011con.sup"
Type Spp2Pgs -h for more help.
libspp2pgs & Spp2PgsNet*.dll

The core and its CLR library wrapper for .NET framework applications.
Three classes play the main role:

    PgsEncoder, encoding and writing a pgs file.
    FrameStream, reading subtitles and rendering subtitles into image.
    Spp2Pgs, an entrance for all other things. Also reading images from FrameStream and sending them to PgsEncoder.
---

It seems to be Windows-based (at least build files are *.vcxproj), and has some x86 asm (yasm) functions,
but better than nothing, I guess ...

This specific fork was not updated in four years (since 2016), so some subtle (!) bugs may exist ....

For license it says: GPL-3.0 License 

Found this one via google and this forum post from 2019:

http://forum.doom9.org/showthread.php?t=176899

Also found subtitler program written in C#/.Net (so it sorta run under Linux/Mono):

https://nikse.dk/SubtitleEdit/Help#linux

But I have no idea how (if at all) it can be compiled under Linux .. (Arch package basically repackages
binary file). Found via https://unix.stackexchange.com/questions/278001/open-hdmv-pgs-subtitles-in-gnu-linux

Also there was KDE5 based subtitle editor with some speech recognition,
but apparently it was archived by developer last year:

https://github.com/maxrd2/SubtitleComposer

Ah, no I'm blind , it was moved into KDE!

https://invent.kde.org/multimedia/subtitlecomposer/-/commits/master

So, some interesting findings, but making any of them to work (at least on my machine) will be ..non-trivial.