Renewal of secret and shadows in secret image sharing

Abstract

Secret image sharing (SIS) is an important method to protect the security of secret images. When part of the shadows generated by the secret sharing is leaked or when the secret image is restored, the shadows and the secret need to be renewed. Aiming at secret image and shadow image renewal, a scheme for renewing secret image and shadow images is proposed. The scheme is to multiply the original and renewed shadow of the corresponding serial number to get a new shadow over finite fields. Our scheme can realise the renewal of the secret image and shadows and has characteristics of the variable threshold, secure public transmission, variable size, and lossless recovery. This paper theoretically analyses and proves the security of the proposed scheme and verifies the effectiveness through a large number of experiments.