This system is a prototype built out of several online tutorials (mainly this 1 for screen printout )and some extra ideas I've thrown in for masking off the face of the user to create an alpha area.

The user turns on the webcam view, shrinks the mask around the shape of their face and then takes a snapshot of themselves. This then generates a JPEG which is saved to a file so the user can insert themselves into online content. Alternatively this system could be used in conjunction with a securitycam system.