数码技术测定虹膜色彩的可行性

Feasibility of color measurement for iris using digital camera

背景:天然虹膜颜色个体差异大、种类多,常规肉眼比色由于比色方法、比色环境及操作者的个体差异的局限性,选色结果往往不能令患者满意。目的:评价数码技术应用于虹膜配色的可行性与合理性。方法:使用数码相机,在稳定光源环境(D65标准光源)、固定拍摄参数(光圈f/2.8,快门1/45s,感光度ISO100,图像格式RAW)条件下,拍摄148例单眼球缺失病例的虹膜,患者年龄24～49岁;图像经Camera RAW for Adobe Photoshop7.0专业软件处理后,观察虹膜的色彩特征,采集虹膜色彩数据,运用"HSB模型"滑杆显示不同患者天然虹膜的色相(H)、饱和度(S)、亮度(B)数值。使用SPSS13.0统计软件作进一步描述性分析及χ2检验。结果与结论:148例单眼球缺失患者运用"HSB模型"比色,141例义眼虹膜色质良好,与健眼协调;4例色质稍偏差,细看能区别出修复体;3例与健眼虹膜有较大差别。提示依据孟赛尔HVC颜色系统,运用"HSB模型",借助数码相机、计算机并结合相关软件,对不同颜色进行测定、分析,方法科学、具有量化性,比色快速、方便、准确。所取设备易取,具有一定的临床应用价值。

BACKGROUND： Because of individual differences in the natural iris color and colorimetric method, colorimetric environment and the operator, color Selection results often do not make a patient satisfaction. OBJECTIVE： To evaluate the reliability and reasonability of iris color matching by using the digital camera. METHODS： The irises from 148 volunteers aged between 24 to 49 years were recorded by a digital camera in studio environment （D65 standard illuminant）. Photographs were taken under a set exposure parameters （AE f/2.8, 1/45 s, ISO 100） and saved in RAW image file format. The characteristics of color of the tested iris were visually observed, and the color values were obtained from the digital images using Camera RAW for Adobe Photoshop 7.0. Through partial color picking analysis by Photoshop 7.0 to exhibit different levels and the H, S and B value which compared by using HSB Model sliders. All data were analyzed in descriptive statistics and compared in X^2 analysis using SPSS 13.0 software package. RESULTS AND CONCLUSION： 148 patients for lack of a single eye with little chromatism that was not easily detected by naked eyes were randomly selected and HSB model was applied for color matching, of these, 141 enjoyed good color quality which is consistent with that of healthy eye; 4 were slightly different from other iris in terms of their color quality and restoration which can be identified when being looked at closely：3 are substantially different from neighboring iris. Based on the Munsell H.V.C. color system, by application of HSB model and digital cameras computers and certain software, to test and analyze different colors is a scientific and quantitative method which matches color quickly and conveniently. Also, the materials needed are easily acquired. Therefore, it is of clinical application value.