I am doing an AR work for windows desktop (x64). This involves camera tracking + real time compositing on blackmagic (both I/O).
I’ve learned that UE is primaraly single threaded during game play (not dev, please correct me if i am wrong).
If it involves camera tracking and specially realtime compositing, which will the main driving force? CPU clock, CPU cores or GPU or Mix of these or something else.
more info:
Game logic - nothing much. just few color transformations only.
FPS - 50-60
** i am looking at game play. Not development setup **
P.S.
at the moment i am looking at i5-9600k, R5-3600x & i7-9700k(worse case). cost is a concern. 
other confing - 16GB Ram + Evo SSD.
Thanks.