Enter<Device parameters>→<Stream setup>, can setting stream
Stream type: Main stream, sub-stream,both of them are video stream, also can do customize setting for size,frame,rate,Frame interval, level. All these setting
are used for adjust video (or preview) image quality and storage file bit. Main stream are default choose, sub-stream can be choose, but not default choose.
Full frame rate is default output frame rate of camera,MAX.frame rate
Frame interval: also means Key frame, 1 frame interval, will influence with image quality and stream.
.
Sub-stream's option open, then"Real video"--"choose stream"---"sub-stream" can be choose
JPEG quality: Recommended value 20, the lower value, the better image quality