摘要
为了对BIM模型在遭受攻击后进行快速有效的版权保护,提出一种稳健的BIM数据盲水印算法。首先,以原数据中的多面网格要素为单位,提取多面网格对象的所有网格顶点构造复数序列,对复数序列做DFT变换得到幅度系数和相位系数;其次,利用QIM方法,将经过Logistic映射置乱得到的水印信息,嵌入到DFT变换域的幅度系数中;最后,运用离散傅里叶逆变换(inverse discrete fourier transform,IDFT)得到含水印信息的BIM数据。在水印提取中,通过投票原则提取水印,无需原始数据参与,是一种盲水印算法。在实际应用中,因BIM模型中顶点坐标的相同值较多,被用来嵌入水印的有效载体较少,为解决这一问题,在误差容许范围内对原始坐标数据加入了随机噪声,以嵌入不同的水印,间接地增加了水印嵌入容量。实验表明,该算法能够很好的控制水印嵌入引起的数据误差,嵌入水印对BIM数据的精度影响小,且对BIM数据常见的随机删除实体、旋转、平移攻击和特殊攻击具有较好的稳健性,可为BIM数据的所有权提供切实可行的依据。
In order to protect the copyright of BIM model quickly and effectively after attack,a robust blind watermarking algorithm for BIM data is proposed.Firstly,based on the polyhedral grid elements of the original data,all the grid vertices of the polyhedral grid object are extracted to construct the complex sequence,and the amplitude coefficient and phase coefficient are obtained by DFT transformation of the complex sequence.Secondly,the watermark information obtained by Logistic mapping scrambling is embedded into the amplitude coefficient of the DFT transform domain by using QIM method.Finally,the BIM data with watermark information is obtained by IDFT transform.In watermark extraction,the watermark is extracted by voting principle without the participation of original data,so it is a blind watermarking algorithm.In practical application,because of the same value of Vertex coordinates in BIM model,there are few effective carriers used to embed watermark.in order to solve this problem,random noise is added to the original coordinate data in the range of error tolerance to embed different watermarks and indirectly increase the embedding capacity of watermarks.The experimental results show that the algorithm can control the data error caused by watermark embedding,and the embedded watermark has little influence on the accuracy of BIM data.It has good robustness to the common random deletion entities,rotation,translation attacks and special attacks of BIM data,and can provide a feasible basis for the ownership of BIM.
作者
蒋美容
张黎明
陈金萍
JIANG Meirong;ZHANG Liming;CHEN Jinping(Faculty of Geomatics,Lanzhou Jiaotong University,Lanzhou 730070,China;National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring,Lanzhou 730070,China;Gansu Provincial Engineering Laboratory for National Geographic State Monitoring,Lanzhou 730070,China;Yangzhou Micro Map Geographic Information Technology Co.,Ltd.,Yangzhou 225002,China)
出处
《测绘地理信息》
CSCD
2021年第S01期165-169,共5页
Journal of Geomatics
基金
国家自然科学基金(41761080)
兰州市人才创新创业科技计划(2016-RC-59)
甘肃高等学校产业支撑引导项目(2019C-04)
兰州交通大学优秀平台支持项目(201806)
