I. Introduction
Due to the natural, non-intrusive and contactless acquisition pattern of facial data, the face recognition (FR) technology has been extensively accepted by public and applied widely in our daily life [11], [12]. This effective and reliable biometrics recognition patten has spread in numerous practical applications like time attendance, bank service, access control, boarder entry & exit, criminal investigation, etc. In recent years, massive researches and achievements towards face recognition via 2D face images and 3D face scans have been studied and reported for enhancing and improving the recognition performance of a face recognition system [1], [25], [26], [2], [18], [9], [35]. However, a potential menace hiding behind these successful researches, called spoofing attacks, threats insidiously the security of a face recognition system. Spoofing attack is defined as an intrusive act of deceiving a biometric system by presenting a fake evidence or copied biometric trait to obtain valid authentication [28]. Particularly, in face related spoofing attacks, the fake evidence is commonly presented as a photograph or a video of a valid user which are captured at distance or collected via internet. Due to the development of 3D scanning and 3D printing techniques, the convenient manufacture of 3D mask provides an easier way to intruders for masquerading as a registered person in a FR system. Moreover, a social public website “Thats My Face”
http://www.thatsmyface.com
provides the manufacturing service of wearable 3D masks, which only demands to offer one frontal photo (a side-view photo demanded as option). Unfortunately, the convenient face data acquisition and the face model manufacture, which should be the advantage of face recognition, become gradually the jeopardy and the calamity to a face recognition system.