双水印模型在医疗信息管理中的应用

DUAL WATERMARKING MODEL AND ITS APPLICATION IN MEDICAL INFORMATION MANAGEMENT

大量医疗信息的产生不仅造成存储这些信息的空间不断增大,对传输成本和传输的安全性也带来了巨大的挑战。为了提高医疗信息的有效性、传输过程的安全性,以及提高信息存储容量,提出利用块加编码和非下采样Contourlet变换(NSCT)的双水印模型,通过三层安全机制,实现医疗信息保护。首先把病人的信息嵌入此病人的指纹图像中,然后把指纹图像嵌入病人医学图像之中;其次通过设计块加编码,解决文本字符的编码问题;最后注册密钥机制,来提高医疗信息的安全。实验结果表明此方案提高了水印的鲁棒性和增强医疗信息的安全。

The generation of substantial amount of medical information not only leads to constant increasing in space of storing them, the cost and safety of the transmission also faces huge challenges. In order to raise the effectiveness of medical information and safety of transmission process, as well as enhance the information storage capacity, we present a dual watermarking model which uses blocks-plus- encoding and non-sampled Contourlet transform （NSCT）, through three-layer security mechanism to achieve the protection of medical information. The first layer is to embed patient＇ s information into his/her fingerprint images, and then to embed the fingerprint images into patient＇s medical images. The second layer is to solve the text character encoding issue by designing the blocks-plus-encoding. The third layeris the key registration mechanism for enhancing the safety of the medical information. Experimental results show that the proposed method improves the robustness of watermarking and enhances the safety of medical information.