中文摘要：

重点地区的TIN DEM数据具有重要的保护价值。根据数据的组织方式,结合密码学中的经典理论,提出一种基于置乱-代换机制的TIN DEM信息伪装方法。首先在频率域上利用Tent混沌映射生成的混沌序列对原始数据进行置乱;然后再利用中国剩余定理将置乱结果在空间域上进行数值代换处理,得到最终的伪装数据,并讨论了信息还原的方法;实验分析表明该方法的伪装效果良好,安全性能较高,能够满足TIN DEM数据的信息伪装要求,保障其安全存储和传输。

英文摘要：

TIN DEM data of the key areas have significant protection value.According to the data organization form,this paper proposes a new method of TIN DEM information disguising based on permutation-substitution theory which is a classical theory in cryptography.Firstly,the original data is permuted using the chaotic sequence which is generated by Tent map in frequency domain.Secondly,in the basis of Chinese remainder theorem,the final disguised data could be obtained by the numerical substitution in spatial domain,and the method of information reduction is also discussed in this paper.Finally,the disguising effectiveness and security performance of the method are validated by analyzing the experiments,which can meet the requirements of TIN DEM information disguising and also could guarantee the storage and transmission security for the TIN DEM data.