目的 为进一步提高变换域水印的鲁棒性，解决多分辨率小波变换对三角形网格形状的限制，提出一种基于局部特征点的变换域水印算法。方法 首先根据经度角和纬度角对模型分区，并求出局部特征点；其次由局部特征点的模长与非局部特征点模长的均值构成的比值组成2维矩阵，对2维矩阵进行离散小波变换，并修改小波系数中的各分辨率层的中高频系数来嵌入水印；最后通过逆向离散小波变换得到空域信号，修改3维模型局部特征点的模长以得到含水印的3维网格模型。结果 本文方法能够不受平移、旋转、均匀缩放和顶点重排序的影响，并能有效抵抗噪声、简化、剪切、细分、量化和联合攻击等一系列的常见攻击。结论 实验结果表明，该算法具有很好的鲁棒性和不可见性，对模型的网格形状无严格要求。

Objective To improve the robustness of transform domain watermarking and solve the limits of the grid shape in multi-resolution wavelet transform, a transform domain-watermarking scheme of 3D models based on local feature points is presented in this paper. Method 3D models are partitioned through longitude and latitude angles to get the local feature points. Two-dimensional matrices are composed by the ratio of the length of the local feature points and the other points in this region. The discrete wavelet transform is carried out on the two dimensional matrix modifying the wavelet coefficients of each layer in the intermediate frequency and high frequency coefficients to embed the watermarking. Then, the airspace signal is obtained by the inverse discrete wavelet transform and the length of the local feature points is modified to obtain a 3D watermarked mesh model. Result The proposed watermarking scheme is robust against attacks such as translation, rotation, uniform scaling, vertex re-ordering, noise, simplification, cropping, subdivision, quantization, combination attacks and so on. Conclusion The experimental results show that this watermarking scheme has good robustness and imperceptibility. Besides, it has no strict requirement for the shape of the mesh model.