数字博物馆文物三维模型基于谱分析的数字水印技术

Spectral Analysis Based Watermarking Algorithm for 3D Mesh of Cultural Heritage in Digital Museum

提出了一种保护数字博物馆文物三维网格模型版权的鲁棒非盲水印算法。采用谱分析的方法将三维模型的空间信息和颜色信息转换到谱空间,使得水印能量能够在模型上得到充分的扩散,使算法针对各种变换均有较强鲁棒性;采用模型分片技术,在模型子块上独立嵌入和提取水印,提高了运算效率和整体鲁棒性,并使算法获得抵御剪裁攻击的能力;采用基于薄板样条函数的待测模型标准化方法,获得抵抗重建网格拓扑关系攻击和仿射变换攻击的能力;采用QR-code技术对水印信息进行高效方便的编码和解码,QR-code基于Reed-Solomon的容错机制提高了算法的鲁棒性。实验结果证明添加水印后的三维模型有着较好视觉质量,同时对三维模型的仿射变换、坐标点随机噪声、模型光滑、重新网格化、模型裁剪都有较好的鲁棒性。

A robust non-blind watermarking algorithm for 3D mesh of cultural heritage in digital museum was proposed based on spectral analysis to protect the copyright. The algorithm employed spectral analysis to modify mesh shapes and color in their transformed domain and the energy of watermark would diffuse all over the mesh, and in result it attributed global robustness to algorithm. The algorithm employed mesh partitioning to improve computational efficiency and the global robustness especially mesh resection. The algorithm employed watermarked mesh standardization based on TPS（thin-plate spine） transformation to improve the robustness of remesh and affine transformation. The algorithm employed QR-code to code and decode the information of watermark. The distortion correction technology of QR-code improved algorithm global robustness. Experiment shows that the visual quality of watermarked mesh is good. Experiment also shows that algorithm is robust to affine transformation, random noise, mesh smoothing, resmesh, and partial resection.