Growing concern the world over, related to personal and property safety has propelled rapid growth of security and surveillance related technologies. The biometric system is one such that can provide accurate and reliable scheme for person verification. The main aim of biometric based security system is to make sure that rendered service is accessed only by valid user. Biometric systems are of two types: unimodal and multimodal. In these multimodal biometric systems are gaining more popularity as it is capable of addressing some of the challenges involved in designing a biometric systems such as: non-universality, noise in sensed data, large intra-user variations and susceptibility to spoof attacks. In this paper, we give a brief overview of multimodal biometrics and its advantages, challenges, drawbacks and limitations. We also discuss the performance evaluation of multimodal biometrics for two and three modalities for different combinations of algorithms.

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Image Processing Biometrics Security