Video- and Audio-based Biometric Person Authentication Motivation: Applications. Modalities and their characteristics. Characterization of a biometric authentication system. Problem formulation: authentication and identification. Structure of a biometric system. Biometrics is the science of identifying or verifying the identity of a person based on physiological or behavioral characteristics.

Methods of Identity Verification Is their any need for automatic biometric identification? Possessions (what you have) keys, cards, badges -lost or stolen -can be shared -can be duplicated -no remote or over-the-phone use Knowledge (what you know) passwordspasswords, PIN, user id -can be forgotten -can be shared -can be guessed Biometric (what you are) fingerprints, face, iris, ?

Applications of Automatic Identification and Authentication 1.physical access control (computer, car, house, room, bank, border crossing, boarding planes, … ) 2.access to services, facilities, information (computer, bank account, database) 3.user identity monitoring for authorized use (is it still the user who did the login?, authorized car driver? ) 4.surveillance, security, crime prevention 5.many other situations (authorization to collect a child) Note: applications 3. and 4. cannot be handled by classical identity verification procedure (3. requires continuous operation, 4. is covert) Market size is huge Market size is huge …..

Biometric: any measurement of person’s physiological traits or behavior fingerprint face iris retinal scan ear shape hand geometry infrared (face, body parts) speech handwriting signature lip movements keystroke dynamics gait odor Physiological: Behavior:Genetic: tissue sample Market share

hand geometry iris scan fingerprint face recognition and more …

Characterization of a biometric system Cost Recognition performance (false accept, false reject, identification precision) measured by: FAR and FAR, or ROC curves,FAR and FARROC curves User acceptability (friendliness) – depends on many factors: ease of use, ease of enrolment, prejudice, invasive/non invasive, speed of authentication … (retinal scan: low, face recognition: high, widely used on ID cards) Covert/Overt (covert: face recognition, gait; overt: signature, iris scan) One shot/continuous (keystrokes, face recognition can verify identity over time) Contact/Remote/Tele (Tele: can identity by verified over the phone?, Remote: physical contact needed?) Non-Repudiation (denial should not be possible) Attended / Unattended Subterfuge resistance (e.g. is just a recording presented? ) Human verifiable? (can be used semi-automatically)? Properties of individual biometrics Performance of selected biometrics

Problems: Identification vs. Authentication Identification (1:N matching): the system uses the biometric to determine the corresponding person from a database containing many people, or decides that the person is not enrolled in the database. Authentication (1:1 matching, identity verification): the system matches the input biometric against a single biometric record. The latter could be stored on a card presented at the transaction time, or looked up in a database with the help of a key such as an account number or employee ID. The output of the match is either “Yes” if the two biometrics match or “No” otherwise. Often during the enrollment process, we need to employ an identification system to make sure the person is not already enrolled and the subsequent usages are authentication instances using the unique number assigned to the user during the enroll. Structure of a biometric system

Literature:  Biometrics: Personal Identification in a Networked Society, Jain, Bolle, Pankanti, Eds., Kluwer Press. ISBN  Biometrics: Advanced Identify Verification: The Complete Guide, by Julian D. M. Ashbourn, 352 pages Bk&Cd-Rom edition (October 2000), Springer Verlag; ISBN:  Biometrics: Identity Verification in a Networked World, by Samir Nanavati, 224 pages 1 edition (March 15,2002) John Wiley & Sons; ISBN: