Prepare to migrate away from irrKlang

[tombogle]

In response to this message:
SIL is a non-profit org that produces non-commercial software to benefit people from indigenous language communities. We have been including irrKlang in one of our libraries (SIL.Media) for many years. I checked your license to confirm that we are fully compliant. I had previously downloaded version 1.6 of the DLL, which we distribute with some of our software. However, I see on the Downloads page that it is no longer possible to download without some kind of license. What do we need to get a license so that we can download future versions?

I received this reply:
yes - there won't be a lot of updates anymore for the free version - sorry for that. irrKlang is developed to be used mainly in games and
game development has changed quite a bit during the last years. Also, we don't sell any more new licenses because of that. Best to switch to another library.

Best Regards,

Nikolaus Gebhardt :: Ambiera e.U.

So, while we can continue to use the version of irrKlang we have, we probably need to start looking at alternatives going forward.

[rmunn]

A few possible alternatives we might consider:

• https://github.com/videolan/libvlcsharp — C# bindings to the libvlc library (written in C), which is the backend that powers the VLC media player. Does a lot more than just audio; if we want to extend SIL.Media to be able to play videos (presumably short ones) then this would be a good option. LGPL license, so no problems with using it as a library.
• https://github.com/naudio/NAudio — apparently popular (5.8k stars) library that does only audio. MIT license.
• https://github.com/dotnet/Silk.NET — also quite popular (4.5k stars), MIT license, but currently undergoing a rewrite to version 3.0 so if we switch to this now we'd be in v2.0 and might have to rewrite SIL.Media later.

All three of those look good to my first, superficial glance, but I haven't looked into their APIs at all so I currently have no idea how hard or easy each of those libraries would be to switch to.

[tombogle]

We do already use NAudio for some things. I'm not sure what (if anything) irrKlang buys us beyond what NAudio gives us.