Random Girds-Based Threshold Visual Secret Sharing with Improved Contrast by Boolean Operations

摘要

In recent years, visual secret sharing (VSS) by random grids (RG) has gained much attention since it can avoid pixel expansion problem as well as has no codebook needed, which has acceptable visual quality based on the internal structure of the designed scheme. Till now, the previous schemes still suffer from low visual quality, from our point of view, and visual quality decreases fast when n increases. In this paper, a new RG-based VSS with improved visual quality based on Boolean operations is proposed, based on two different quality-improved approaches and gaining both advantages. The proposed scheme has several features such as (k, n) threshold, no codebook design, and no pixel expansion. Moreover, it has higher contrast compared with related schemes.