1. Introduction
Personnel security is becoming increasingly important in today's
modern world [1]. Biometric-based access control is one of the most
important technologies for cyber–physical security, and has received
increasing attention over the past two decades. In the competitive businessworld
of today, the need and demand for a biometric physical security
solution have never been higher. The biometricmarket is increasing
each year and this trend is set to continue, due to the increasing need for
security at borders, and in buildings, airports, etc. [2]. At its core, it aims
to identify a person with one or more of their body features, such as
their face, hand, fingerprint, or voice [1–3]. These biometric modalities
can be deployed for different applications including; searching for people,
remote access control, and secure corridors in airports.
To date, there has been a large amount of work done in biometrics,
with most of it focusing on using a single biometric mode. Recently,
the trend has been to build robust person identification systems based
on multimodal approaches, i.e., a combination of biometric features.
However, to obtain a robust multimodal solution, it is of benefit to employ
individual modalities which have good performance in isolation.