Single-random-phase holographic encryption of images

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

11 Scopus Citations
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Original languageEnglish
Pages (from-to)22-28
Journal / PublicationOptics and Lasers in Engineering
Online published15 Feb 2016
Publication statusPublished - Feb 2017


Title1st International Symposium on 3D Imaging, Metrology, and Data Security (3DIM-DS)
Period1 September 2015


In this paper, a method is proposed for encrypting an optical image onto a phase-only hologram, utilizing a single random phase mask as the private encryption key. The encryption process can be divided into 3 stages. First the source image to be encrypted is scaled in size, and pasted onto an arbitrary position in a larger global image. The remaining areas of the global image that are not occupied by the source image could be filled with randomly generated contents. As such, the global image as a whole is very different from the source image, but at the same time the visual quality of the source image is preserved. Second, a digital Fresnel hologram is generated from the new image, and converted into a phase-only hologram based on bi-directional error diffusion. In the final stage, a fixed random phase mask is added to the phase-only hologram as the private encryption key. In the decryption process, the global image together with the source image it contained, can be reconstructed from the phase-only hologram if it is overlaid with the correct decryption key. The proposed method is highly resistant to different forms of Plain-Text-Attacks, which are commonly used to deduce the encryption key in existing holographic encryption process. In addition, both the encryption and the decryption processes are simple and easy to implement.

Research Area(s)

  • Holographic encryption, Double-random-phase encryption, Bi-directional error diffusion, Single-random-phase encryption, OPTICAL ENCRYPTION, PLAINTEXT ATTACK, VULNERABILITY, DOMAIN, KEYS