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On the Analysis and Generalization of Extended Visual Cryptography Schemes

DaoShun Wang·Feng Yi·Xiaobo Li·Ping Luo·Yiqi Dai
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Abstract

An Extended Visual Cryptography Scheme (EVCS) was proposed by Ateniese et al. [3] to protect a binary secret image with meaningful (innocent-looking) shares. This is implemented by concatenating an extended matrix to each basis matrix. The minimum size of the extended matrix was obtained from a hypergraph coloring model and the scheme was designed for binary images only [3]. In this paper, we give a more concise derivation for this matrix extension for color images. Furthermore, we present a (k, n) scheme to protect multiple color images with meaningful shares. This scheme is an extension of the (n, n) VCS for multiple binary images proposed in Droste scheme [2].

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DaoShun Wang, Feng Yi, Xiaobo Li, Ping Luo, Yiqi Dai. 2006-10-31. On the Analysis and Generalization of Extended Visual Cryptography Schemes. https://arxiv.org/abs/cs/0610172

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