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Title
Abstract
Introduction
Numerical Simulations and Analysis
Trpe Cryptanalysis
Trpe Method Resistance to Chosen-Plaintext Attacks
Trpe Method Resistance to Known-Plaintext Attacks
Conclusion
References
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Engineering
Electronic, Optical and Magnetic Materials

Optical triple random-phase encryption

Profile image of Maria YzuelMaria Yzuel

2017, Optical Engineering

https://doi.org/10.1117/1.JBO.22.4.041011
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Abstract

We propose an optical security technique for image encryption using triple random phase encoding (TRPE). In the encryption process, the original image is first double random phase encrypted. The obtained function is then multiplied by a third random phase key in the output plane, to enhance the security level of the encryption process. This method reduces the vulnerability to certain attacks observed when using the conventional double random phase encoding (DRPE). To provide the security enhancement of the proposed TRPE method, three attack cases are discussed: Chosen-plaintext attacks (CPA), Known-plaintext attacks (KPA) and chosen-ciphertext attacks (CCA). Numerical results are presented to demonstrate feasibility and effectiveness of the proposed method. Compared with conventional DRPE, the proposed encryption method can provide an effective alternative and has enhanced security features against the above-mentioned attacks.

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References (52)

  1. B. Javidi, ed., Optical and Digital Techniques for Information Security (Advances Sciences and Technologies for Security Applications), Springer-Verlag, (2005).
  2. O. Matoba, T. Nomura, E. Pérez-Cabré, M. S. Millán, and B. Javidi, "Optical techniques for information security," Proceedings of the IEEE , 97, 1128-1148 (2009).
  3. A. Alfalou and C. Brosseau, "Optical image compression and encryption methods," Adv. Opt. Photon. 1, 589-636 (2009).
  4. M. S. Millán and E. Pérez-Cabré, Optical data encryption, Optical and Digital Image Processing: Fundamentals and Applications, G. Cristobal, P. Schelkens and H. Thienpont, ed., Verlag: Wiley-VCH, ( 2011).
  5. W. Chen, B. Javidi and X. Chen, "Advances in optical security systems," Adv. Opt. Photon. 6, 120-155 (2014).
  6. S. Liu, C-L. Guo and J. T. Sheridan, "A review of optical image encryption techniques," Opt. Lasers Eng. 57, 327-342 (2014).
  7. B. Javidi and E. Ahouzi, "Optical security system with Fourier plane encoding," Appl. Opt. 37, 6247-6255 (1998).
  8. B. Javidi, A. Sergent, and E. Ahouzi, "Performance of double phase encoding encryption technique using binarized encrypted images," Opt. Eng. 37, 565-569 (1998).
  9. B. Javidi, A. Carnicer, M. Yamaguchi, T. Nomura, E. Pérez-Cabré, M. S. Millán, N. K. Nishchal, R. Torroba, J. F.Barrera, W. He, X. Peng, A. Stern, Y. Rivenson, A. Alfalou, C. Brosseau, C. Guo, J. T.
  10. Sheridan, G. Situ, M. Naruse, T.Matsumoto, I. Juvells, E. Tajahuerce, J. Lancis,W. Chen, X. Chen, P.W. H. Pinkse, A. P.Mosk, and A.Markman,, "Roadmap on optical security,"J. Opt. 18, (2016).
  11. W. Zamrani, E. Ahouzi, A. Lizana, J. Campos, and M. J. Yzuel, "Optical image encryption technique based on deterministic phase masks," Opt. Eng. 55, 103108 (2016).
  12. B. Javidi and T. Nomura, "Securing information by use of digital holography," Opt. Lett. 25, 28- 30 (2000).
  13. E. Tajahuerce and B. Javidi, "Encrypting three-dimensional information with digital holography," Appl. Opt. 39, 6595-6601 (2000).
  14. X. Peng, Z. Cui, and T. Tan, "Information encryption with virtual-optics imaging system," Opt. Commun. 212, 235-245 (2002).
  15. W. Chen, X. Chen, and C. J. R. Sheppard, "Optical image encryption based on diffractive imaging," Opt. Lett. 35, 3817-3819 (2010).
  16. P. Clemente, V. Durán, V. Torres-Company, E.Tajahuerce, and J. Lancis, "Optical encryption based on computational ghost imaging," Opt. Lett. 35, 2391-2393 (2010).
  17. Y. Shi, T. Li, Y. Wang, Q. Gao, S. Zhang, and H. Li, "Optical image encryption via ptychography," Opt. Lett. 38, 1425-1427 (2013).
  18. Y. Zhang and B. Wang, "Optical image encryption based on interference," Opt. Lett. 33, 2443- 2445 (2008).
  19. N. Zhu, Y. Wang, J. Liu, J. Xie, and H. Zhang, "Optical image encryption based on interference of polarized light," Opt. Express 17, 13418-13424 (2009).
  20. A. Alfalou and C. Brosseau, "Dual encryption scheme of images using polarized light," Opt. Lett. 35, 2185-2187 (2010).
  21. E. Pérez-Cabré, M. Cho, and B. Javidi, "Information authentication using photon-counting double-random-phase encrypted images," Opt. Lett. 36, 22-24 (2011).
  22. P. Refregier and B. Javidi, "Optical image encryption based on input plane and Fourier plane random encoding," Opt. Lett. 20, 767-769 (1995).
  23. A. V. Zea, J. F. Barrera, and R. Torroba, "Experimental optical encryption of grayscale information," Appl. Opt. 56, 5883-5889 (2017).
  24. S. Xi, X. Wang, L. Song, Z. Zhu, B. Zhu, S. Huang, N. Yu, and H. Wang, "Experimental study on optical image encryption with asymmetric double random phase and computer-generated hologram," Opt. Express 25, 8212-8222 (2017).
  25. G. Li, L. Dayan, and G. Situ, "Optical image encryption based on classical double random phase encoding: Cyphertext-only attack via speckle correlation," in Digital Holography and Three- Dimensional Imaging, OSA Technical Digest (online) (Optical Society of America, 2017), paper
  26. Th2A.4.
  27. G. Li, W. Yang, D. Li, and G. Situ, "Cyphertext-only attack on the double random-phase encryption: Experimental demonstration," Opt. Express 25, 8690-8697 (2017).
  28. Y. Frauel, A. Castro, T. J. Naughton, and B. Javidi, "Resistance of the double random phase encryption against various attacks," Opt. Express 15, 10253-10265 (2007).
  29. Y. Frauel, A. Castro, T. J. Naughton, and B. Javidi, "Security analysis of optical encryption," in Un-manned/Unattended Sensors and Sensor Networks II, E. M. Carapezza, ed., Proc. SPIE 5986, 25- 34 (2005).
  30. U. Gopinathan, D. S. Monaghan, T. J. Naughton, and J. T. Sheridan, "A known-plaintext heuristic attack on the Fourier plane encryption algorithm," Opt. Express 14, 3181-3186 (2006).
  31. X. Peng, P. Zhang, H. Wei, and B. Yu, "Known-plaintext attack on optical encryption based on double random phase keys," Opt. Lett. 31, 1044-1046 (2006).
  32. G. Situ, G. Pedrini, and W. Osten, "Strategy for cryptanalysis of optical encryption in the Fresnel domain," Appl. Opt., 49, 457-462 (2010).
  33. W. Qin and X. Peng, "Vulnerability to known-plaintext attack of optical encryption schemes based on two fractional Fourier transform order keys and double random phase keys," J. Opt. A, Pure Appl. Opt., 11, (2009).
  34. X. Peng, H. Wei, and P. Zhang, "Chosen-plaintext attack on lensless double-random phase encoding in the Fresnel domain," Opt. Lett. 31, 3261-3263 (2006).
  35. W. He, X. Peng, and X. Meng, "A hybrid strategy for cryptanalysis of optical encryption based on double-random phase-amplitude encoding," Opt. Laser Technol., 44, 1203-1206, (2012)
  36. P. Kumar, A. Kumar, J. Joseph, and K. Singh, "Vulnerability of the security enhanced double random phase amplitude encryption scheme to point spread function attack," Opt. Lasers Eng. 50, 1196-1201 (2012).
  37. Y. Zhang, D. Xiao, W. Wen, and H. Liu, "Vulnerability to chosen-plaintext attack of a general optical encryption model with the architecture of scrambling-then-double random phase encoding," Opt. Lett. 38, 4506-4509 (2013).
  38. A. Carnicer, M. Montes-Usategui, S. Arcos, and I. Juvells, "Vulnerability to chosen-cyphertext attacks of optical encryption schemes based on double random phase keys," Opt. Lett. 30, 1644-1646 (2005).
  39. X. Peng, H. Tang, and J. Tian, " Ciphertext-only attack on double random phase encoding optical encryption system," Acta. Phys. Sinica, 56, 2629-2636, (2007).
  40. X. Liu, J. Wu, W. He, M. Liao, C. Zhang, and X. Peng, "Vulnerability to ciphertext-only attack of optical encryption scheme based on double random phase encoding," Opt. Exp., 23, 18955-18968, (2015).
  41. J. Wu, W. Liu, Z. Liu, and S. Liu, " Correlated-imaging-based chosen plaintext attack on general cryptosystems composed of linear canonical transforms and phase encodings," Opt. Commun., 338, 164-167, (2015).
  42. T. Li and Y. Shi, "Attack on optical double random phase encryption based on the principle of ptychographical imaging," Chin. Phys. Lett., 33, (2016).
  43. M. Liao, D. Lu, W. He, X. Peng, "Optical cryptanalysis method using wavefront shaping," IEEE Photonics J., 9, (2017).
  44. B. Hennelly and J. T. Sheridan, "Optical image encryption by random shifting in fractional Fourier domains," Opt. Lett. 28, 269-271 (2003).
  45. C. Li, "Cracking a hierarchical chaotic image encryption algorithm based on permutation," Sign. Proc., 118, 203-210, (2016).
  46. X. C. Cheng et al, "Security enhancement of double-random phase encryption by amplitude modulation," Opt. Lett. 33, 1575-1577 (2008).
  47. A. M. Elshamy, A. N. Z Rashed, Abd El-Naser A. Mohamed, O. S. Faragalla, Y. Mu, "Optical Image Encryption Based on Chaotic Baker Map and Double Random Phase Encoding,"J. of Lightwave Technology, 31, 2533-2539 (2015).
  48. E. Ahouzi et al., "Pattern recognition with a phase-shifting interferometric correlator Discrimination-capability enhancement," Appl. Phys. B Lasers and Opt. 64, 331-338 (1997).
  49. R. Gerchberg and W. Saxton, " A practical algorithm for the determination of phase from image and diffraction plane pictures," Optik 35, 237-246 (1972). communications at National Institute of Posts and Telecommunications. His research involves optical devices and systems design.
  50. Angel Lizana completed his MSc degree in physics and his PhD in physics at the Autonomous University of Barcelona (Spain) in 2006 and 2011, respectively. His research interests include polarimetry and diffractive optics. He has been a postdoctoral scientist in the Laboratoire de Physique des Interfaces et des Couches Minces (LPICM) of the École Polytechnique (France) in 2011-2012 and in 2013-2014. He has been a postdoctoral researcher at the Autonomous University of Barcelona (UAB), since 2014.
  51. Juan Campos received his BSc and MSc degrees in physics from University of Zaragoza, Spain, in 1981 and his PhD degree at the Universitat Autònoma de Barcelona, Spain, in 1986. Currently, he is a full professor at this University. He has worked in the fields of image quality evaluation, optical pattern recognition, spatial light modulators, polarimetry, and surface shape metrology. He is a fellow member of the SPIE, OSA, and EOS.
  52. María J. Yzuel obtained the MSc and PhD degrees in physics from the University of Zaragoza (Spain) in 1962 and 1966, respectively. She has been a professor of optics at the Universities of Zaragoza and Granada, and from 1983 to 2011 she has been a full professor at the Autonomous University of Barcelona. She is currently Emeritus Professor. She has worked in the field of diffraction image theory and image quality evaluation as well as in optical pattern recognition. She has also contributed during several years in the field of image techniques in medical diagnosis (gammagraphy and radiology). She is a Fellow of OSA, IOP, SPIE, EOS, SEDOPTICA and RSEF. She was the president of the Spanish Optical Society from 1993 to 1996. She was a vice-president of the International Commission of Optics from 1990 to 1996 and currently from 2011 to 2017. She was the secretary general of the European Optical Society from 1996 to 1998. Member of the SPIE Board of Directors 2001-2003. She received in 2005 the SPIE Board of Directors Award. She was Vice-President, President and Past-President of the SPIE from 2007 to 2010.

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