Colour quality of facial prostheses in additive manufacturing
Colour quality of facial prostheses in additive manufacturing
复制标题
DOI：
10.1007/s00170-017-1480-x
复制
发表时间：
2018-04-01
影响因子：
3.4
通讯作者：
Wuerger, Sophie
中科院分区：
文献类型：
--
作者：
Sohaib, Ali;Amano, Kinjiro;Wuerger, Sophie
增材制造技术的最新进展通过对肤色轮廓的计算优化改善了3D面部假体的逼真色彩再现。假体表面的颜色外观取决于表面的光谱特性和场景照明。考虑到日常环境，假体表面的颜色在各种照明下应该是恒定的，尽管迄今为止对面部假体的这种评估取得的成功有限。在这项研究中，在整个增材制造过程中评估了颜色质量，即从颜色配置文件优化到3D面部假体的颜色再现。针对典型肤色样本优化的颜色配置文件被应用于制造具有两种皮肤类型（高加索人和中国人）的面部假体。通过色差度量CIEDE2000和光谱相似性对相应的真实的皮肤数据评估颜色质量。通过引入再现颜色恒定指数来估计不同照明下假体表面的恒定颜色外观。在所有皮肤类型和面部区域上，假体和真实的皮肤之间的CIEDE2000平均约为7.2，这略大于可接受的感知误差。在从CIE标准日光和荧光灯中选择的不同照明下，水平相对恒定。再现色恒常性指数的范围从0.34到0.89，这是非常相似的水平观察到的传统的颜色恒常性数据在视觉科学。光谱误差接近通过计算从数字RGB颜色的光谱重建。这些结果表明，建议的面部假体的颜色管理可以满足日常环境中的各种照明的颜色质量的要求。并对制造过程中遗留误差的产生原因及进一步改进进行了讨论。
Recent progress in additive manufacturing technology has improved the realistic colour reproduction of 3D facial prostheses with computational optimisation of skin colour profiles. The colour appearance of the prosthetic surface depends on both the spectral characteristics of the surfaces and the scene illumination. Considering everyday environments, the colours of prosthetic surfaces should appear constant under various illuminations, although such evaluations on facial prostheses have had limited success to date. In this study, colour quality was assessed throughout the additive manufacturing process, namely, from the colour profile optimisation to the colour reproduction on the 3D facial prostheses. Colour profiles optimised for typical skin colour samples were applied to manufacture facial prostheses with two skin types, Caucasian and Chinese. The colour quality was assessed by the colour difference metric CIEDE2000 and spectral similarity against corresponding real skin data. The constant colour appearance of the prosthetic surfaces under different illuminations was estimated by introducing a reproduction colour-constancy index. The CIEDE2000 between the prosthetic and real skins was approximately 7.2 on average over all skin types and facial areas, which is slightly larger than the acceptable perceptual error. The level was relatively constant under different illuminations selected from the CIE standard daylight and fluorescent lights. The reproduction colour-constancy index ranged from 0.34 to 0.89, which is remarkably similar to the level observed in traditional colour constancy data in vision sciences. Spectral errors were close to those obtained by computational spectral reconstruction from digital RGB colours. These results suggest that the proposed colour management for facial prostheses may satisfy the requirement of colour quality in everyday environments with various illuminations. The causes and further improvement of the remaining errors in the manufacturing process are also discussed.