An improved image authentication technique using random-sequence based secret-sharing scheme

A new image authentication technique using random sequence based secret sharing scheme with a data repair capability is proposed. For each block of image, an authentication signal is generated together with the binarized block content, which is transformed into several shares using the secret sharing scheme. The parameters which have been involved in the algorithm, are carefully selected so that the maximum number of shares can be generated to generate stego-image. In the process of image authentication, an image block is marked as tampered if the authentication signal computed from the current block content does not match with that extracted from the embedded shares. There after the data repairing is applied to each tampered block by the scheme of reverse secret sharing.