How to overlay pixhawk data on gstreamer video

Hi, is there ways i can overlay pixhawk lflight data on gstreamer video in real time?

my device elements like below:
1.Pixhawk cube orange - raspberry pi - USB webcam ------ mavproxy------- PC- rtsp-server - rtspclient
i figured out overlay images and text on video by gstreamer frame work editing pilpeline and now i want to overlay the pixhawk data on video in real time not recording video.
is there a way?
aprreciate .

Doesnt the video stream just replace the background of the hud in missionplanner? So you have all information already?