First, HTTP Get this URL: http://10.5.5.9/gp/gpControl/execute?p1=gpStream&a1=proto_v2&c1=restart and then you can get a UDP stream by using this URL: udp://10.5.5.9:8554 (you might have a hard time using this in your work...)
NOTE: If using ffplay (ffMPEG), try using the nobuffer
flag, for a low latency stream.
More info can be found here: https://www.reddit.com/r/gopro/comments/2md8hm/how_to_livestream_from_a_gopro_hero4/cr1b193
NOTE: This works in the HERO4 Silver and Black, for HERO4 Session you might want to read HERO4-Session.md on how to wake it up and enter streaming mode.
Since working with UDP protocols and system calls, I recommend using GoProStream tool, which is a easy to use GoPro Streaming client written in Python: https://github.com/KonradIT/GoProStream
For changing the specs of the live stream such as Bitrate, go to the livestreaming tweaks page