Phase-based virtual image encryption and decryption system using Joint Transform Correlator

  • Seo, Dong-Hoan (Department of Electronic Eng., Kyungpook Nat′l University) ;
  • Cho, Kyu-Bo (Department of Electronic Eng., Kyungpook Nat′l University) ;
  • Park, Se-Joon (Department of Electronic Eng., Kyungpook Nat′l University) ;
  • Cho, Woong-Ho (Department of Computer Science, Taegu technical college) ;
  • Noh, Duck-Soo (Department of Electronic and Information Eng., Kyungil University) ;
  • Kim, Soo-Joong (Department of Electronic Eng., Kyungpook Nat′l University)
  • Published : 2002.07.01

Abstract

In this paper a Phase-based virtual image encryption and decryption techniques based on a joint transform correlator (JTC) are proposed. In this method, an encrypted image is obtained by multiplying a phase-encoded virtual image that contains no information from the decrypted image with a random phase. Even if this encryption process converts a virtual image into a white-noise-like image, the unauthorized users can permit a counterfeiting of the encrypted image by analyzing the random phase mask using some phase-contrast technique. However, they cannot reconstruct the required image because the virtual image protects the original image from counterfeiting and unauthorized access. The proposed encryption technique does not suffer from strong auto-correlation terms appearing in the output plane. In addition, the reconstructed data can be directly transmitted to a digital system for real-time processing. Based on computer simulations, the proposed encryption technique and decoding system were demonstrated as adequate for optical security applications.

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