Biblio

When employing biometric recognition systems, we have to take into account that biometric data are considered sensitive data. This has raised some privacy issues, and therefore secure systems providing template protection are required. Using homomorphic encryption, permanent protection can be ensured, since templates are stored and compared in the encrypted domain. In addition, the unprotected system's accuracy is preserved. To solve the problem of the computational overload linked to the encryption scheme, we present an early decision making strategy for iris-codes. In order to improve the recognition accuracy, the most consistent bits of the iris-code are moved to the beginning of the template. This allows an accurate block-wise comparison, thereby reducing the execution time. Hence, the resulting system grants template protection in a computationally efficient way. More specifically, in the experimental evaluation in identification mode, the block-wise comparison achieves a 92% speed-up on the IITD database with 300 enrolled templates.

Biometric recognition systems based on ultrasound images have been investigated for several decades, and nowadays ultrasonic fingerprint sensors are fully integrated in portable devices. Main advantage of the Ultrasound over other technologies are the possibility to collect 3D images, allowing to gain information on under-skin features, which improve recognition accuracy and resistance to spoofing. Also, ultrasound images are not sensible to several skin contaminations, humidity and not uniform ambient illumination. An ultrasound system, able to acquire 3D images of the human palm has been recently proposed. In this work, a recognition procedure based on 2D palmprint images collected with this system is proposed and evaluated through verification experiments carried out on a home made database composed of 141 samples collected from 24 users. Perspective of the proposed method by upgrading the recognition procedure to provide a 3D template able to accounts for palm lines' depth are finally highlighted and discussed.