一种基于图元特征的地图符号库零水印算法

针对现有零水印算法不适用于包含多种数据类型的地图符号库的版权保护问题,提出了一种基于图元特征的地图符号库零水印算法。以地图符号的图元总数、图元数量最多的图元类型和图元数量最少的图元类型3个图元特征的组合作为关键特征,具有较好的稳健性和可区分性,从而保障了零水印的鲁棒性和唯一性。算法未对地图符号数据进行任何修改,保证了地图符号的精度。实验结果表明:该零水印算法在符号移动、符号添加和符号删除等攻击方式下均具有较好的鲁棒性,是一种较为理想的地图符号库版权保护方法。

A Zero-watermarking algorithm of map symbol library based on Item characteristics

Because the existing watermarking algorithms can not be applied to the copyright protect1on of map symbol library which contains a variety of data types,this paper proposes a zero-watermarking algorithm of map symbol library based on the item characteristics of map symbols.The algorithm takes the item amount,the item type which has the maximum items and the item type which has the minimum items as key characteristic to build zero-watermarking.The combination of them is robust and distinguishable to ensure the robustness and uniqueness of zero-watermarking.The algorithm doesn't change any map symbols,this ensures the accuracy of map symbols.The experiment shows that the zero-watermarking algorithm has high robustness in symbol moving,symbol adding and symbol deletion.Then,it's an ideal method for map symbol library copyright protection.