Although not a legal advice, but EmguCV comes with dual licensing options, if you are going to have your product open sourced, then go ahead you are all fine. If you want to have a closed coursed, and commercial usage of the application, then you require a commercial license from them. Commercial licensing has some terms that you need to be clear of.
This much of information, as Richard has already mentioned, is clearly available on their website too,
Licensing: - Emgu CV: OpenCV in .NET (C#, VB, C++ and more)[
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