基于视觉感知与菱形编码的图像隐写算法

Image Steganographic Algorithm Based on Visual Perception and Diamond Encoding

为提供较大的隐写容量和保持良好的载密图像质量,提出一种基于视觉感知和菱形编码的图像隐写算法。根据人类视觉系统,针对人眼对图像的高中低灰度区、纹理区及平滑区的敏感度的不同,在不同区域选择嵌入不同数量的秘密信息;同时为了尽可能减少对图像像素值的改变,采用改进的菱形编码来嵌入秘密信息。实验结果表明,与HVS-OPAP算法相比,该算法图像的嵌入容量提高了4.09%,获取的隐写图像具有更好的不可感知性,同时峰值信噪比平均提高了1.5dB,而且该算法具有抗RS隐写分析能力,安全性更高。

In order to provide larger capacity of the hidden secret messages and maintain a good visual quality of stego-image,a novel image steganography based on visual perception and Diamond Encoding（ DE） is proposed. According to the Human Visual System（HVS）,human eyes have different sensitivity on high gray areas,middle gray areas and low gray areas,texture areas and smooth areas. The different amounts of secret messages are embedded in the different areas of cover images. Especially,the modified DE is used to minimize the change of the image pixel value. Experimental results show that the proposed method can effectively improve the embedding capacity than HVS-OPAP algorithm by 4 . 09%, while stego-image has better imperceptibility, PSNR average of 1. 5 dB, and RS steganalysis methods can not detect whether the secret information is embedded,so it has a better security.