Before you proceed with any head tracking software, make sure you have properly configured your PS3 Camera !

Manual here: PS3 Camera Setup

OpenTrack Download: HERE

Video does not mention this, but please make sure you select the PS3 Camera as on the screenshot below:

DELANCLiP + OpenTrack video manual by Grim Reapers

Alternative OpenTrack Manual

There is also availabe more in depth manual for setting up OpenTrack with your head tracker on the link below:

A complete guide to set up Head-tracking (Opentrack)