面向电子航海图分发服务的多级可逆水印算法

M ulti-level reversible watermarking algorithm for electronic navigational chart distribution service

针对电子航海图(ENC)分发过程中存在的版权归属不清、泄露责任难以认定的问题,在顾及ENC对数据扰动敏感、精度要求高特点的基础上,以高隐蔽性ENC数据多级分发版权保护为目标,提出了一种面向ENC分发服务的多级可逆水印算法。首先通过精度移位创造独立水印信息嵌入空间确保算法的可逆,其次通过控制水印信息嵌入的坐标位置减小对数据精度的干扰,然后利用极坐标转换的方式隐藏水印信息,最后基于水印信息的提取与再嵌入实现动态多级分发。实验结果表明:该算法具有较好的不可感知性和充足的水印容量,能有效实现ENC多级分发过程中的版权溯源,预防数据盗版。

To address the issues of unclear copyright ow nership and difficulty in determining leak responsibility during the distribution of Electronic Navigational Charts(ENC),and considering the sensitivity of ENC to data perturbation and its high precision requirements,this paper proposes a multi-level reversible watermarking algorithm aimed at high stealth ENC data multi-level distribution copyright protection.The algorithm first creates independent watermark information embedding space through precision shifting to ensure reversibility.Secondly,it minimizes interference with data precision by controlling the coordinates of watermark information embedding.Then,it conceals watermark information using polar coordinate transformation.Finally,the algorithm implements dynamic multi-level distribution based on the extraction and re-embedding of watermark information.Experimental results show that this algorithm offers good imperceptibility and sufficient watermark capacity,effectively enabling copyright traceability and preventing data piracy in the multi-level distribution of ENC.