基于快速响应码的灰度视觉密码方案设计

Design of Gray Visual Cryptography Scheme Based on Quick Response Code

在保证快速响应码识读效率的基础上,为提高其秘密载荷能力,基于快速响应码的模块识别特性,提出一种面向灰度图像且像素不扩展的(n,n)异或视觉密码方案.该方案根据模块识别单元的结构建立灰度值与系列模板之间的映射关系,进而设计不同的视觉密码分享矩阵集合,对秘密进行分享,并利用Matlab和Photoshop对方案性能进行测试分析.实验验证和理论分析表明,该方案秘密信息恢复算法为线性时间算法,可承载的秘密载荷量为载体图像规格的9倍,且能够抵抗压缩、旋转和剪切等一般几何攻击.

To improve the secret payload capacity of the quick response code with the basis of ensuring the decoding efficiency,an(n,n)XOR visual cryptography scheme oriented to grayscale image without size expansion has been proposed based on the module identification characteristics of the quick response code.It establishes the mapping relationship between the gray value and the series template according to the structure of the module identification unit,and then designs different sharing matrix sets of visual cryptography scheme to encrypt the secret image.Finally,Matlab and Photoshop are utilized to test and analyze the performance of the scheme.Experimental results and theoretical analysis show that the secret recovery algorithm of the proposed scheme is a linear time algorithm,the secret payload amount is 9 times as the specifications of the carrier image,and it can resist general geometric attacks such as compression,rotation and shear.