Biometric data hiding: A 3 factor authentication approach to verify identity with a single image using steganography, encryption and matching

Digital Steganography exploits the use of host data to hide a piece of information in such a way that it is imperceptible to a human observer. Its main objectives are imperceptibility, robustness and high payload. DCT Domain message embedding in Spread Spectrum Steganography describes a novel method of using redundancy in DCT coefficients. We improved upon the method of DCT embedding by using the sign of the DCT coefficients to get better accuracy of retrieved data and more robustness under channel attacks like channel noise and JPEG compression artifacts while maintaining the visual imperceptibility of cover image, and even extending the method further to obtain higher payloads. We also apply this method for secure biometric data hiding, transmission and recovery. We hide iris code templates and fingerprints in the host image which can be any arbitrary image, such as face biometric modality and transmit the so formed imperceptible Stego-Image securely and robustly for authentication, and yet obtain perfect reconstruction and classification of iris codes and retrieval of fingerprints at the receiving end without any knowledge of the cover image i.e. a blind method of steganography, which in this case is used to hide biometric template in another biometric modality.