The first step is to have openFrameworks installed. You can find the instructions on how to install it on their website (the app was developed on version 0.9.8). Once you have OF installed and made sure you can run the examples, copy and paste the 'Hair' folder inside apps/myApps, type $ make, and then $ make RunRelease.
*openFrameworks version: of_v0.10.1_osx_release *The blobs are detected using ofxOpenCV