基于像素值排序最值阶跃响应的可逆信息隐藏

针对现有明文域可逆信息隐藏方案对于单个像素值修改过程中仅嵌入单比特秘密信息,提出一个基于像素排序值(pixel value ordering,PVO)阶跃响应的可逆信息隐藏方案。PVO对像素块排序后的最值进行预测和修改实现秘密信息的可逆嵌入,具有高保真的特性。利用PVO后的参考像素来确定高保真阶跃修改量,然后通过阶跃处理进行块内冗余像素的选择,最终通过排序序列与像素位置的映射关系来实现信息的嵌入。方案每修改单个像素值信息能够实现多比特秘密信息的嵌入,并且由像素排序确定得到的阶跃修改量能够保证信息提取后图像的无损恢复。经仿真实验验证,在达到同样嵌入容量要求条件下,研究结果较先前基于预测扩展处理的像素值排序方案能够大幅减少像素修改的数量,并且低负载条件下峰值信噪比性能指标得到显著提升。

An Efficient Reversible Data Hiding Scheme based on Maximum Step Response obtained by Pixel Value Ordering

In order to optimize the problem of embedding only one bit secret information during the process of modifying a single pixel value in the existing reversible information hiding schemes, a reversible information hiding scheme based on maximum step response obtained by pixel value ordering is proposed in this paper. Pixel value ordering ,which predicts and modifies the maximum value of the ordered pixel blocks to achieve reversible hiding of secret information, has the characteristics of high fidelity. The reference pixels sorted by the pixel values are used to determine the high fidelity step response modification. Then, the redundant pixels in the block are selected by step response processing. Finally, the information is embedded by mapping the ranking sequence to the location of the pixels. Each modification of the single pixel value information in the scheme can realize the embedding of multi-bit secret information, and the step modification determined by the pixel ranking can ensure the lossless restoration of the image after information extraction. The simulation results show that the proposed scheme can significantly reduce the number of pixel modifications compared with the previous scheme based on predictive expansion processing under the same requirement of embedding capacity. Meanwhile, this reversible data hiding scheme can also improve the peak signal-to-noise ratio evaluation index compared with previous Pixel Value Ordering methods by an average of 0. 01db.