Lossless Information Hiding in Images

2.6. Reversible Secret Sharing–Based Schemes

Secret sharing plays an important role in data encryption. Shamir et al. [56] proposed an (r, n)-threshold prototype based on Lagrange polynomial interpolation. In this model, the secret data are encrypted into n shares. If r or more than r shares are polled, the secret can be decrypted. Otherwise, if r − 1 or fewer shares are collected, no meaningful information can be revealed. Thien et al. [57] extended Shamir et al.'s model into image secret sharing, i.e., hiding a secret image in a set of noiselike shadow images. Visual cryptography [58] is another useful technique for image secret sharing. It employs the properties of human visual system and thus maintains the advantage that the secret content ...