Challenges for the implementation and revision of international biometric standards demonstrated by the example of face image data

Abstract

Travel documents such as the electronic passport (ePass) ensure that each person can be uniquely identified by a single document. The development of new ePass security chip technologies allows for the inclusion of biometric properties in the data carrier of the ePass. The International Civil Aviation Organization (ICAO) has determined a personal photograph as being the interoperable feature for all global travel documents; ICAO [Gro04] regulations reference quality requirements for facial images as defined in ISO standard ISO/IEC 19794-5 [Intb]. Project FIReBIRDs goal is to prepare an international facial image database for conformity tests based on ISO/IEC 19794-5 [Intb], to analyze the requirements in the regulating documents, and to develop suggestions for adaptations and extensions of these standards. The FIReBIRD database shall provide a well-defined ground truth for level 3 conformance testing. For this purpose the specifications in the standard were thoroughly analyzed and in some parts refined to allow for a precise definition of ground truth. We show with two examples that there might be a defined common-sense definition for some parameters, but they are not measurable and their specification is not scientifically founded: the definition of full frontal view and the definition of eye and hair colors. Our results show that specifications and requirements should always be checked for necessity, practicability and usability and that a continued review and revision of biometric standards is necessary.