생체정보와 위상 랩핑 방법을 이용한 암호화 및 복호화 시스템

Abstract

In this paper, we propose an improved image encryption and fault-tolerance decryption method using bio-information and phase wrapping method in the frequency domain. An encrypted image in the encryption process is denoted the product of a phase-encoded arbitrary image and a random phase image. The encrypted image is zero-padded and Fourier transformed. Its real-valued data and bio-information image are phase-encoded. Both encrypted key and decrypting key are made of proposed phase wrapping method. The decryption is simply performed based on 2-f setup with spatial filter by Fourier transform for multiplication phase-encoded fingerprint image and the keys. The proposed method using arbitrary image, which does not contain any information from the original image, prevents the possibility of counterfeiting from unauthorized people and also can be used as a current spatial light modulator technology by phase encoding of the real-valued data. Computer simulations show the validity of the encryption scheme and the robustness to noise of the encrypted key or the decryption key in the proposed technique.