Export dewarped streams from Media Server

I'd like to be able to define preset slices from a fisheye view (as with the PTZ presets) and export them as streams from the media server. I could then integrate those streams into web applications, etc.

I would access these sub-streams either through Nx Witness, or via the Video API; eg:
GET /media/<cameraid>/<substreamid>.<format>
or
GET /media/<cameraid>/<ptzPresetId>.<format>?fov=<90, 180, etc.>

One benefit of this is that a dozen streams at 640x480 is still fewer pixels than the full fisheye view at 2560x1920.

And the shoot-for-the-moon bonus feature: PTZ controls per-stream could be an option, such that an operator could take PTZ control of an exported stream, either through Nx Witness or via the API, and other viewers of that stream would see their viewpoint change.