Penrose tiling for visual secret sharing

Visual secret sharing (VSS) has the advantage that the decryption is based on our human visual system without participation of any computational devices. However, traditional VSS schemes are only for sharing raster images with regard to pixels, which lead to that the secret image will be aliased when enlarged and its pixels are shared in rectangular way only. In this paper, we will introduce a VSS scheme for vectorized images based on Penrose tiling. Penrose tiling is with the merits of vectorization and nonperiodicity. These properties are applied to the proposed scheme so as to share those vectorized images; the basic unit of secret sharing could be any graphical shapes instead of pixels or rectangular regions only in the traditional methods. Our experiments show the effectiveness of the proposed scheme.