基于表面粗糙度的三维模型质量评价研究

数字水印的嵌入会引起三维模型数据的失真，正确评价含水印三维模型的质量可以为三维水印算法的测评提供统一标准。提出了一种新的三维模型质量的评价方法，它首先利用网格模型中二面角为基本度量单位计算出整个原始三维模型的粗糙度，然后在嵌入水印以后用同样的方法计算出含水印三维模型的粗糙度，最后得到嵌入水印前后粗糙度的增量，并将其作为水印嵌入对三维模型造成的失真度的度量。大量实验结果表明，相比传统的质量评价方法，该方法更加适用于三维网格模型。该质量评价方法还可用于评价各种水印攻击对含水印三维模型造成损害的程度。

Quality Assessment for 3-D Model Based on Surface Roughness

In the process of 3-D model watermarking, emhedding watermark will make distortion on the 3-D model. Assessing the quality of 3-D watermarked model correctly can hchave as one of the principles of assessing 3-D watermarking scheme. In this paper, a quality assessment measure for the 3-D model was proposed. To compare with traditional quality assessment methods such as SNR ratio and Hausdorff, this method is more suitahle for 3D models. First, we calculated the roughness of the mesh model with the dihedrals which is the primitive of a 3D model. Second, we calculated the roughness of the watermarked model after watermarking. Last we calculated the increment of roughness between the original mesh and the watermarked mesh in order to assess the distortion made by watermarking. Moreover, the proposed method can estimate the distortion of watermarked mesh model made by various attacks.