Biometric privacy using visual cryptography, halftoning and watermarking for multiple secrets

It is important to secure the privacy of digital face image that are stored in central database. To impart privacy to such biometric face images, first the digital face image is split into two such that, each of it gives no idea of existence of the original face image and the original image can be retrieved only when both split images available. To achieve this, Visual Cryptography, Halftoning along with Digital Watermarking are employed. The method can be extended to preserve the privacy of a maximum of any n images.