High Capacity Reversible Data Hiding in Encrypted Images by Patch-Level Sparse Representation
High Capacity Reversible Data Hiding in Encrypted Images by Patch-Level Sparse Representation
复制标题
通过补丁级稀疏表示在加密图像中隐藏大容量可逆数据
DOI：
10.1109/tcyb.2015.2423678
复制
发表时间：
2016-05-01
影响因子：
11.8
通讯作者：
Guo, Xiaojie
中科院分区：
文献类型：
--
作者：
Cao, Xiaochun;Du, Ling;Guo, Xiaojie
加密图像中的可逆数据隐藏已引起隐私安全和保护领域的广泛关注。该领域先前方法的成功表明，利用图像内部的冗余可以实现卓越的性能。具体而言，由于局部结构（如斑块或区域）中的像素具有很强的相似性，它们可以被大量压缩，从而产生较大的隐藏空间。在本文中，为了更好地探索相邻像素之间的相关性，我们建议在隐藏秘密数据时考虑斑块级稀疏表示。广泛使用的稀疏编码技术已经证明，一个斑块可以由一个过完备字典中的一些原子线性表示。由于稀疏编码是一种近似解，主要的残差被编码并自嵌入到载体图像中。此外，学习到的字典也被嵌入到加密图像中。由于稀疏编码的强大表示能力，可以获得较大的空闲空间，因此数据隐藏者可以在加密图像中嵌入更多的秘密信息。大量实验表明，所提出的方法在嵌入率和图像质量方面显著优于现有方法。
Reversible data hiding in encrypted images has attracted considerable attention from the communities of privacy security and protection. The success of the previous methods in this area has shown that a superior performance can be achieved by exploiting the redundancy within the image. Specifically, because the pixels in the local structures (like patches or regions) have a strong similarity, they can be heavily compressed, thus resulting in a large hiding room. In this paper, to better explore the correlation between neighbor pixels, we propose to consider the patch-level sparse representation when hiding the secret data. The widely used sparse coding technique has demonstrated that a patch can be linearly represented by some atoms in an over-complete dictionary. As the sparse coding is an approximation solution, the leading residual errors are encoded and self-embedded within the cover image. Furthermore, the learned dictionary is also embedded into the encrypted image. Thanks to the powerful representation of sparse coding, a large vacated room can be achieved, and thus the data hider can embed more secret messages in the encrypted image. Extensive experiments demonstrate that the proposed method significantly outperforms the state-of-the-art methods in terms of the embedding rate and the image quality.