一种基于GF（2^3）的（K,N）有意义无扩张图像分存方案  

Meaningful （K,N） Free Expansion Image Sharing Scheme Based on GF（2^3）

作　　者：欧阳显斌[1] 邵利平[1] 

机构地区：[1]陕西师范大学计算机科学学院,西安710119

出　　处：《计算机科学》2015年第12期251-256,共6页Computer Science

基　　金：国家自然科学基金资助项目(61100239);教育部高等学校博士学科点专项科研基金资助项目(20110202120002);陕西省科技新星计划资助项目(2011kjxx17);陕西省自然科学基金资助项目(2011JQ8009);中央高校基本科研业务费支持项目(GK201402036)资助

摘　　要：传统有意义图像分存存在像素扩张,通常只对分存信息以较短的认证信息进行甄别,从而导致重构的秘密像素真实性无法准确鉴别。针对此问题,提出一种基于GF（2^3）的（K,N）有意义无扩张图像分存方案。在该方案中,首先生成加密映射表并利用秘密像素的位置信息对秘密像素进行加密;然后将秘密像素的认证信息和加密像素在GF（2^3）有限域下进行（K,N）分存,嵌入到掩体图像对应的像素中;最后将映射表的生成密钥进行（K,N）分存,计算每个子密钥的MD5值并公布到第3方公信方以防止掩体图像持有者作弊。实验结果表明,所提方案能准确地识别出秘密图像攻击区域,不存在任何像素扩张,掩体图像与秘密图像等大且嵌入分存信息的掩体图像具有较好的视觉质量。There is pixel expansion in conventional meaningful image sharing schemes which usually use short authenti- cation information to verify the correctness of sharing information and bring defect that the facticity of the reconstructed secret image pixels cannot be accurately identified. To address these problems, a meaningful （K, N） free expansion image sharing scheme based on GF（2^3） was proposed. In the proposed scheme, firstly a key is used to generate an encryption mapping table and then this table and secret image pi-xel location information are used to encrypt secret image pixels. Secondly （K, N）-threshold scheme based on GF（2^3） is used to share the ciphered pixels and pixels authentication information and then they are embedded into N cover images. Finally the key which is used to generate encryption mapping table is also shared into N sub-keys by （K, N）-threshold scheme and the sub-keys＇ MD5 values are published to the third reliable party to prevent cheating from distributed cover image holders. The experimental results show the proposed scheme can accurately detect attacked regions in reconstructed secret image. By comparing with conventional methods, the proposed scheme does not have any pixel expansion and distributed cover images have better visual quality.

关 键 词：图像分存 有意义图像分存 (K N)门限方案 GF有限域 无扩张 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]