Traditional visual secret sharing (VSS) encodes the original secret image into n shares, and each share is of equal importance. However, in some scenarios, we need to make a difference between the participants according to the levels of their importance. Therefore, the capability of each share to recover the original secret image will be different. In this paper, we proposed a weighted (k,n)-threshold random grid VSS(RG-VSS) with multiple decrytions and lossless recovery. When we get k or more shares for decryption, we will recover different levels of the original image because of the different weights of the shares. More importantly, the secret information can be recovered by OR and XOR operations in our scheme. When we get all the n shares and using the XOR operation to recover the image, we can recover the secret information losslessly. The experimental results and analyses show that our scheme outperforms the related schemes.
Keywords: lossless recovery; multiple decryptions; random grid; visual secret sharing; weighted.