Ianal but i think usually these things cone down to: is it reasonable to expect privacy in the situation (e.g. filming someone in their home through a window is

Ianal but i think usually these things cone down to: is it reasonable to expect privacy in the situation (e.g. filming someone in their home through a window is different than someone in the street just happening to be in the background of your video). I don't think most people would reasonably expect privacy in the context of a staff meeting.