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Sharing secret color images using cellular automata with memory

Gonzalo Alvarez·Luis Hernandez·Angel Martin
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Abstract

A {k,n}-threshold scheme based on two-dimensional memory cellular automata is proposed to share images in a secret way. This method allows to encode an image into n shared images so that only qualified subsets of k or more shares can recover the secret image, but any k-1 or fewer of them gain no information about the original image. The main characteristics of this new scheme are: each shared image has the same size that the original one, and the recovered image is exactly the same than the secret image; i.e., there is no loss of resolution.

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Gonzalo Alvarez, Luis Hernandez, Angel Martin. 2003-12-17. Sharing secret color images using cellular automata with memory. https://arxiv.org/abs/cs/0312034

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