Here are some already published scientific papers about BioID technology:

PDF document Robert W. Frischholz, Alexander Werner: Avoiding Replay-Attacks in a Face Recognition System using Head-Pose Estimation, AMFG 2003: IEEE International Workshop on Analysis and Modeling of Faces and Gestures, October 17, 2003, Nice, France.
 
PDF document H. Hertlein, Dr. R. Frischholz, Dr. E. Nöth: Pass Phrase Based Speaker Recognition for Authentication, in Arslan Brömme and Christoph Busch, editors, BIOSIG 2003: Biometrics and Electronic Signatures, GI-Edition, Lecture Notes in Informatics, pp. 71-80, Darmstadt, Germany, July 2003.
 
PDF document Kirchberg, Jesorsky, Frischholz: Genetic Model Optimization for Hausdorff Distance-Based Face Localization, International ECCV Workshop on Biometric Authentication, Springer, Lecture Notes in Computer Science, LNCS-2359, pp. 103-111, Copenhagen, Denmark, June 2002.
 
PDF document Jesorsky, Kirchberg, Frischholz: Robust Face Detection Using the Hausdorff Distance, Audio- and Video-Based Biometric Person Authentication, 3rd International Conference, AVBPA 2001, Halmstad, Sweden, June 2001. Proceedings, Springer (ISBN 3-540-42216-1).
 
PDF document Frischholz, Dieckmann: BioID: A Multimodal Biometric Identification System, IEEE Computer, Vol. 33, No. 2, February 2000.

 
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