Best performance for a parrallel task

Hello,
the new Job System sounds great, but i am not sure if it is the most optimal way to handle a costly Task that should run in the Background.
I have a Project on for the HoloLens in wich i constantly search the Enviroment for an QR Code, this is pretty cost effective since it runs OpenGL.
How could u handle this Problem the best way? shedulding a Job every third Frame to search for QR codes?

Kind Regards