Abstract: Reversible data hiding (RDH) is a special data hiding technique in which the original cover medium can be exactly extracted from the marked content. By this technique, besides the embedded secret data, the cover medium can be recovered from the marked data as well. Unlike the conventional data hiding techniques such as digital watermarking and steganography, the specific property of RDH is the perfect recovery of both of the cover medium and embedded secret data. In general, RDH is a fragile technique and it poses no robustness against any possible attack. For a desired embedding capacity and a cover data such as uncompressed digital image, to achieve better embedding performance, the encoder expects to minimize the embedding distortion (measured by PSNR in dB) to obtain a good marked image quality. This technique has attracted considerable interests from the data hiding community in the past two decades, and there is a rapid increase of applications that utilize RDH including image authentication, medical image processing, and stereo image coding, etc. In this paper, current RDH techniques for digital images are briefly reviewed by introducing the following four types of schemes: lossless compression based schemes, integertointeger transform based schemes, expansion and shifting based schemes, and content adaptive schemes.

Key words: reversible data hiding (RDH), lossless compression, histogram modification, integertointeger transform, performance evaluation

摘要： 可逆隐藏(reversible data hiding, RDH)是一种能够将原始载体从含密载体中无损恢复的特殊信息隐藏技术.使用可逆隐藏不仅能从含密载体中提取所嵌入信息，同时也能将原始载体从含密载体中无损恢复.不同于数字水印和隐写这2类传统的信息隐藏技术，可逆隐藏主要注重于嵌入算法的可逆性以及含密载体和原始载体之间的失真度量.一般而言，可逆隐藏不具有任何鲁棒性，其性能评价主要关注于含密载体和原始载体之间的嵌入失真.由于这种无损恢复的特性，近20年来，可逆隐藏在信息隐藏领域中得到了很大程度的关注，并且可逆隐藏技术也在某些领域中得到了初步的实际应用.以数字图像为载体，简要回顾了现有的可逆隐藏技术，包括四大类方法：基于无损压缩的可逆隐藏、基于整数变换的可逆隐藏、基于扩展和移位的可逆隐藏以及图像内容自适应的可逆隐藏.

关键词: 关键词可逆隐藏, 无损压缩, 直方图修改, 整数变换, 性能评价中图法分类号TP391