Half-sphere VR?

Hello, How do I tell the VR plugin that I'm pointing it at a half-sphere video stream, rather than a full-sphere video stream? The reason I'm asking: I've been messing around on my test bench with the 360 demo ( https://developer.jwplayer.com/jw-player/demos/innovation/360-video/ ) and have run into a bit of a problem: With my intended application, the cameras I'll be using are all going to be wall or ceiling mounted, and thus, half-sphere cameras rather than full sphere cameras. I'm also not going to have the kind of server-side processing power needed for the server to do the image manipulations needed to account for it. Thus, I need to be able to tell the player it's a half-sphere video. So what option do I need, and how do I specify it so that the player knows it's looking at a half-sphere video rather than a full-sphere video? Thanks.