利用数码相机测定面部皮肤颜色的初步研究

A study of measurement of facial skin color using digital camera

目的:利用数码相机进行面部皮肤颜色测定的可行性与合理性的研究。方法:在进行颜色采集之前,首先测定实验光源的稳定性。使用Canon EOS20D单反数码相机,在实验光源稳定的时间内,以相同的拍摄参数(快门1/25 s,光圈4.5自定义白平衡,ISO 800)采集122例22～32岁受试人群颌面部的皮肤颜色,拍摄文档保存为Jpeg格式。图像经Adobe photoshop7.0统一校色后,拾取皮肤CIE L*a*b*色度学空间颜色数据,利用SPSS 10.0做统计描述。结果:实验光源在21～70 min内是稳定的,可以达到比色要求。实验测得皮肤的L*a*b*色度学参数范围为:L*49～66,a*7～18,b*5～22。结论:面部皮肤色度参数与测色手段和方式密切相关,数码相机作为面部赝复体的比色方法,在面部皮肤色彩信息全面采集、色彩信息准确传递方面,具有独特优势。

Objective ：To evaluate the reliability and reasonability of maxillofacial skin color match using the digital camera. Methods：The stability of the experimental light source was evaluated before establishing the color measurement. 122 volunteers aged from 22 to 32 years were recorded by a Canon EOS 20D digital camera in studio environment when the light source was stable. Photographs were taken under a set exposure parameters（f/4.5,1/25 s,custom white balance,ISO 800） and saved as JPEG format. The CIE L＊ a＊ b＊ color values were obtained from the digital images using Adobe Photoshop7.0 after color correction. All data were analyzed using SPSS 10.0. Results：The experimental light source was stable in 21 to 70 minutes. It was suitable for color measurement during this period. The color parameters of all tested maxillofacial skin were ： L＊49 - 66, a ＊ 7 - 18, b ＊ 5 - 22. Conclusion ： The assessment of maxillofacial skin color depend on method of measurement and instrument. The method of maxillofacial skin color matching by digital camera seems reliable.