I am using this slightly differently with Rpanion Video Streaming from a Raspberry Pi companion computer.
On Rpanion, Streaming is setup on a web interface as:
Device: Raspberry Pi Camera (V2)
Rotation: 0 degrees
Average Bitrate: 2000 kbps
Video streaming works well on an older android tablet with the latest QGroundControl daily build.
Unfortunately video streaming does not work on a Linux mint 19.3 MATE laptop with the latest daily build.
On the laptop, wireshark shows real-time transport protocol packets being received ie the video stream,
but QGroundControl video window displays the message “WAITING FOR VIDEO”.
I can see the video stream on the laptop using VLC with the same RTSP URL.
QGroundControl Application video settings on both devices are set identially.
The video settings are:
Source: RTSP Video Stream
RTSP URL: rtsp://192.168.10.34:8554/video
Aspect Ratio: 1.777777
File Format: mkv
I hope this information can be of some use.