Random Grids-Based Threshold Visual Secret Sharing with Improved Visual Quality

摘要

Visual secret sharing (VSS) by random grids (RG) has gained much attention since it avoids the pixel expansion problem as well as requires no codebook design. However, most of the previous RG-based threshold VSS still suffer from low visual quality or worse reconstructed secrets when more shares are stacked. In this paper, a new RG-based VSS with improved visual quality is proposed. The random bits are utilized to improve the visual quality as well as to decrease the darkness of the reconstructed secret image in the proposed scheme. Experimental results and analyses show the effectiveness of the proposed scheme.