Greetings :)
I'm a C++ Engineer who specialises in low-level video processing and that includes DirectX, DirectShow, DirectSound etc.
My question for you is- can you please clarify/explain in more details WHAT it is you are looking to use DirectX for? Also, on WIndows 8 and 10 you would be looking to use Windows Media Foundation(WMF).
Both DirectX and WMF are written in, and targetted at C++ developers. C# software for DirectX will not give you performance, nor flexibility - in terms of the number of DirectX "Filters" you can use etc etc.
More later.(If I hear from you)