Building dll for first plugin...

I’m trying to figure out how you build OpenCV (library) to use as a plugin for Unity pro. It sounds relatively simple to call functions in a plugin dll but what I’m reading about compiling OpenCV or openCVsharp they give linux terminal commands…do I have to go download ubuntu on a spare computer to build the dll or can I do it from Vis studio?

I never had a reason to compile code before(thanks unity) so not sure what I’m even looking for…get the source off github, open in V studio and build as a dll somehow? I notice I need to put the dlls in different places depending on the platform but any way I slice it I need to come up with the dll.

Anyone seen any opencv builds available ready for unity to download? Qualcomm vuforia AR doesn’t allow commercial use…Does the ARtoolkit use openCV?

Any advice, this is my first time trying to use a plugin with unity…