基于混沌加密的医学图像安全共享方案

Medical Image's Secure Sharing Scheme Based on Chaos Encryption

采用Shamir秘密共享方案对医学图像进行安全分发是一个重要的研究领域.针对现有方法在影子图机密性和传输效率上的不足,提出基于混沌加密的医学图像安全共享方案.方案首先利用Lagrange插值原理对医学图像进行分解得到若干影子图;然后利用离散混沌函数对影子图进行加密,最后对加密后的影子图采用Shamir秘密共享方案进行分发.本文方案中影子图容量为秘密医学图像的1/r,提高了大容量医学图像传输效率,降低存储空间要求;利用混沌的混合性和对初始值敏感特性对医学图像加密,大大加强医学图像的机密性,防止图像在传输过程中被篡改.实验分析表明,本文方案在传输效率、影子图机密性、图像完整性保护和时间效率上具有优势.算法适用于共享环境下的医学图像安全传输.

Using Shamir secret sharing scheme for medical image＇s secure transmission is a very important research field. Aiming atthe existent algorithm＇s defects in transmission efficiency and shadow images＇ confidentiality, a medical image＇s secure sharing methodbased on chaos encryption is presented in this paper. First,Lagrange interpolation theory is used to divide the original medical imageinto shadow images. Then, a discrete chaos function is utilized to encrypt these shadow images. Finally, the Shamir secret sharingscheme is used to transmit the encrypted shadow images. The shadow image＇s capacity is just 1/r of original secret medical image inour method. Thus ,the transmission efficiency of huge-capacity medical images is improved and the storage requirement is reduced. U-sing the mixture and initial value sensitivity properties of chaos to encrypt medical image can enhance its confidentiality. At the sametime, it can prevent the image from being tampered in transmission procedure. Experimental results show that the presented method hasgood transmission efficiency ,high shadow image＇s confidentiality, integrity protection and good run efficiently. The presented methodcan be applied to online medical image＇s secure transmission.