A face identity classifer based on eigenfaces.

Keyboard interface:
-------------------

Number keys : Learn user
"d" : Detect mode
"c" : Clear classifier

Yarp interface:
---------------

Output port       Bottle contents                 Meaning
/faceclassifier   "user appeared" ID confidence   A user has entered the view of the camera
/faceclassifier   "user disappeared" ID           The user has left the camera view

You can also drive the program via yarp with the following input messages:

Input port            Bottle contents                 Meaning
/faceclassifier-ctrl  "train" ID                      Train for this user
/faceclassifier-ctrl  "detect"                        Switch to detection mode
/faceclassifier-ctrl  "save" sessionname              Save the detected faces 
/faceclassifier-ctrl  "load" sessionname              Load previously detected faces 
/faceclassifier-ctrl  "clear"                         Clears all faces
/faceclassifier-ctrl  "idle"                          Switch to idle mode, mostly frees up cpu
/faceclassifier-ctrl  "errorthresh" value             Set the error threshold (default 0.2)