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Visual cryptography II: Improving the contrast via the cover base

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Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 1189))

Abstract

In Eurocrypt 1994 we proposed a a new type of cryptographic scheme, which can decode concealed images without any cryptographic computations, by placing two transparencies on top of each other and using the decoder's (human) visual systems. One of the drawback of that proposal was a loss in contrast: a black pixel is translated in the reconstruction into a black region, but a white pixel is translated into a grey region (half black and half white). In this paper we propose am alternative model for reconstruction with a different set of operation (which we call the “Cover” semi-group) is proposed. In this model we are able to obtain a better contrast than is possible in the previous one.

Part of this work was done while the authors where visiting the Newton Institute, Cambridge.

Research supported by a grant from the Israel Science Foundation administered by the Israeli Academy of Sciences.

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References

  1. Giuseppe Ateniese, Carlo Blundo, Alfredo De Santis, Douglas R. Stinson, Visual Cryptography for General Access Structures, ECCC Report TR96-012, accepted on Feb 12, 1996 (to appear, ICALP 96).

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  2. M. Naor and A. Shamir, Visual Cryptography, Advances in Cryptology — Eurocrypt 94 Proceeding, LNCS vol. 950, Springer-Verlag, 1995, pp. 1–12.

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Mark Lomas

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© 1997 Springer-Verlag Berlin Heidelberg

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Naor, M., Shamir, A. (1997). Visual cryptography II: Improving the contrast via the cover base. In: Lomas, M. (eds) Security Protocols. Security Protocols 1996. Lecture Notes in Computer Science, vol 1189. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-62494-5_18

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  • DOI: https://doi.org/10.1007/3-540-62494-5_18

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-62494-3

  • Online ISBN: 978-3-540-68047-5

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