FreeTrack is described as 'Head tracking software for webcams, Nintendo Wii Remotes and NaturalPoint cameras (TrackIR, SmartNav and OptiTrack). Tracks a variety of customizable model configurations with up to six degrees of freedom'. There are six alternatives to FreeTrack for Windows, Linux, Self-Hosted solutions and Mac. The best alternative is GiMeSpace Cam Control, which is free. Other great apps like FreeTrack are FaceTrackNoIR (Free, Open Source), linux-track (Free, Open Source), VSeeFace (Free Personal) and Handsfree.js (Free, Open Source).
Head tracking software for TrackIR and SmartNav cameras that provides game profiles, calibration curves, hotkey controls and a 3D display for testing. Works with TrackIR Enhanced games as well as specified mouse, keyboard and joystick emulation software.