Hi,
We are using RICOH Theta S with libuvc_camera, using UVC1.1 (Motion Jpeg mode). The frame is a combined 1280x720 image at 14fps. I think you can use other package like gscam or usb_cam.
I didn’t know about RICOH Theta V, but do you mean you cannot make Theta V work with current driver and packages? I expected V model is upper compatible to Theta S… but checking the spec sheet now, it seems support only H264 streaming… (it means we need UVC1.5 or higher, which is not supported by libuvc 
)