Secret Image Sharing Scheme with Threshold Changeable Capability

In secret image sharing schemes, the threshold may have to be adjusted in case of changes in the security policy and the adversary structure before recovering the secret image. For example, if participants leave the group, their stego images are useless to them and may not be kept safely. As a result, these images can be easily stolen and utilized by intruders, which reduces the security of the scheme. To solve this problem, we propose a novel threshold changeable secret image sharing scheme withNpotential changeable thresholdst1,t2,…,tN. By preparing advance shares for thresholdst1,t2,…,tNand using the two-variable one-way function to generate the identification value, we can change the threshold when necessary. The experiments show that the quality of the stego images in our scheme is satisfactory and the secret image can be recovered without distortion. Moreover, the security analysis shows that we can change the threshold safely.

A Leakproof Secret Sharing Scheme Based on Environment Sensing

A leakproof secret sharing scheme based on environment sensing is proposed, in which the shadows of participants and the shared secret are leakproof, and can be used repeatedly. The counterfeit shadows of the participants and the authentication information of the shared secret can be changed dynamically basing on environment sensing. So the scheme is secure even against a mobile adversary. Besides, through introducing the concept of adversary structure and the transformation of access structure to adversary structure, the secret sharing on general access structure is realized. Compared to the existing schemes, our scheme is more secure and more flexible in practice. Our scheme is particularly suitable for the system which needs to run long time in the open, such as the wireless sensor network and the multi-robots, the property of leakproof based on environment sensing can improve the efficiency and security of these systems effectively.