基于2^k修正和Canny边缘检测的图像隐写

Image Steganography Based on 2^k Correction and Canny Edge Detection

针对信息安全,提出基于Canny边缘检测和2k修正的信息隐藏算法。秘密信息仅仅隐藏在边界像素上,首先利用Canny边缘检测算子检测载体图像的边缘,然后利用伪随机数序列对边缘像素进行重排。为了增强秘密信息的安全性,采用霍夫曼编码把秘密信息变成二进制位流。每个像素隐藏的位数由其灰度值确定。最后,为了增强隐写图像的视觉效果,采用2k修正法进一步减小隐写图像和载体图像之间的误差。实验证明提出的方法比LSB-2和文献[12]的方法更好。

A new algorithm is proposed which is based on Canny edge detector and 2k correction. Firstly, Canny edge detector is applied to detect the edge of cover image and only edge pixels are selected for embedding payload. PRNG is used to randomize the edge pixels in order to enhance security. Then Huffman encoding is practiced to code the secret data before embedded according to Huffman table. Calculate coherent bit length L on the base of relevant edge pixels. Finally, the method of 2^k correction is applied to achieve better imperceptibility in stego image. The experiment shows that the proposed method is better in PSNR and capacity than LSB-2 and scheme [12].