基于预测误差扩展的可逆文本水印算法

为了避免在水印嵌入后造成文本内容的永久性改变,该文借鉴图像中可恢复水印的思想,将预测误差扩展应用于文本文档,提出了一种基于预测误差扩展的可逆中文文本水印算法。该算法以句子为单位,通过上下文搭配度大小选择可替换的词语,最后利用预测误差扩展和混沌序列,实现水印的嵌入。研究结果表明该算法不仅具有较高的安全性,而且能有效地提取水印和无损地恢复出原始文本。

Reversible Text Watermarking Algorithm Based on Prediction Error Expansion

In order to avoid the permanent change of the text content caused by watermark embedding, this paper proposes a reversible watermarking algorithm for Chinese text document based on prediction error expansion englightened by the reversible watermarking for the image. Taking the sentence as the unit, The algorithm selects the words to be replaced according to the size of context collocation degree, and then realizes the embedding by the prediction error expansion and Chaos Sequence. Results show that this algorithm not only has the higher security, but also can extract watermark effectively while maintaining an exact restoration of the original text.