一种水印的容错性提取技术

论文从水印检测过程中可能发生的两类错误入手,讨论了降低检测虚警概率和漏报概率的一般方法。在此基础上,论文构造了一种水印信息预处理方法,即首先通过本原线性移存器(LFSR)产生的m序列将水印信息扩展,然后用加密的扩展信息进行嵌入。在检测时充分考虑到嵌入信息遭受破坏的情况,利用Walsh谱的仿射逼近理论,提出了一种水印的容错性提取技术,使水印可以在大量误码条件下得以恢复,为水印的可靠性检验开辟了一条新的思维途径。

The Watermark Extraction Technique with Errors

In this paper,the two types of errors in watermark detection are introduced firstly.Then the paper makes a discussion on how to decrease the probability of false alarm and probability of false rejection.On the basis of it,a preparation operating method of watermark information is presented,extending the watermark information through the primitive Linear Feedback Shift Register(LSFR)which can produce m-squence,and then embedding the encrypted extend-ing information.Finally,taking damage of the embedded information into account ,a new watermark extraction method using affine approximation theory of Walsh spectrum is put forward in watermark detection.The technique can suit the change of the embedded data and so the watermark can be extracted exactly when a large quantities of embedded data are erroneous.Therefore,a new mode of thinking is developed for reliability detection of watermark in the paper.