If you were using python (a lot of teams find OpenCV easier to use in python), the pynetworktables documentation has a lot of examples of various networktables things you can look at:
http://robotpy.readthedocs.io/projec.../examples.html
Curiously enough, I hadn't ever thought about the fact that one might think that a 'table' needs to be created. I'll add a note about that to our docs.