基于RS码的二值图像认证及篡改定位算法

用于二值图像内容认证和篡改定位的数字水印技术具有重要的实际价值,但却面临着二值图像像素单一、嵌入容量有限且分布不均匀等问题.根据纠错码--RS码的检错原理,提出一种用于二值图像内容认证和篡改定位的脆弱的数字水印算法.该算法利用二值图像的像素值来构造RS码,通过嵌入其校验码来实现对图像的内容认证和篡改定位,一方面保证了其优越的检错能力;另一方面,具有较低的嵌入负载.经实验证明,该算法能有效地检测出二值图像是否被篡改以及篡改发生的位置.此外,在水印信号的生成和提取过程中使用了密钥,确保了水印的安全.

Binary Image Authentication and Tamper Localization Based on RS Codes

Image authentication and tamper localization for binary images are very important but difficult because a binary image has only two values and possesses limited and uneven embedding capacity.In this paper,a fragile digital watermarking algorithm is proposed for binary image authentication and tamper localization based on error correcting codes-RS codes.The superiority of error detection capability is achieved by embedding the check codes of RS codes constructed according to the pixel value in binary images,and in the meanwhile low embedding payload is needed.Experiment results demonstrate that the proposed method can ensure the efficiency in detecting and locating any tampering.In addition,the secret key is used in the process of watermark signal generation and extraction to guarantee the security.