OpenCV is a neat library though. I used it to do some quick and dirty measurements + sprite generation on a couple of hundred shark teeth for a group project in school. We made an educational virtual fossil dig website.
It works, but has it's problem, like memory leaks if you forget to dispose the objects and an upgrade to a newer version had a bug in it's ubuntu binaries that any simple test would have caught.
There is a higher quality commercial wrapper that is only free for gpl'ed solutions.
Which is what I see with some projects, even though the software itself is free, the c# wrapper done by a third party costs money which makes me loathe to use it, as it hinders reuse.
I’ve used both off and on for the last 5 years and generally find Accord.NET to be more pleasant, though most of the attention online goes to OpenCV, so there tends to be more examples for it.