Quality-adaptive threshold visual secret sharing by random grids
Xuehu Yan, Yuliang Lu, Hui Fei Huang, Lintao Liu, Song Wan · 2016
Visual secret sharing (VSS) by random grids (RG) has gained much attention since it can avoid pixel expansion problem without codebook design. However, the previous RG-based threshold VSS schemes still suffer from low visual quality or no threshold. Even the more shares are stacked, the worse reconstructed secrets are revealed. In this paper, a new quality-adaptive threshold RG-based VSS with improved and progressive visual quality is proposed. The proposed scheme decreases the black bits in the white area of the stacked image without white bits in the black area of the stacked image. Experimental results and security analyses show the effectiveness of the proposed scheme.