Tagged Visual Cryptography
Ran-Zan Wang, Shuo-Fang Hsu · IEEE Signal Processing Letters · 2011
This letter presents a method for implementing visual cryptography (VC) in which an additional tag is attached to each generated share. The proposed (t,n), 2 ≤t≤ntagged visual cryptography (TVC) scheme works like a traditional VC scheme does, where the original image is encoded innshares in such a way that the secret can be revealed by superimposing anytor more shares, but knowledge of less thantshares gets no secret information. A notable characteristic of TVC is that an extra tag can be revealed by folding up each share, which provides users with supplementary information such as augmented message or distinguishable patterns to identify the shares. The tagging property can easily be applied to any reported VC scheme to endow the generated shares with more capabilities. Construction methods and simulation results of the proposed (t,n) TVC based on conventional matrix-based VC and probabilistic-VC are illustrated in the letter.