用光谱成像技术与分光光度法测量织物颜色的比较分析

Comparison of spectral imaging and spectrophotometry in fabric color measurement

针对分光光度法与光谱成像技术测量相同织物颜色结果存在差异的问题,选用Datacolor 600型分光光度计、Datacolor Spectravision多光谱成像系统和HIS高光谱成像系统,分别对同一套单色全棉针织物进行测量,探讨了3种仪器测得的颜色参数和光谱反射率差异的原因及规律。通过计算不同仪器间的色差和指数光谱相似性,采用皮尔逊相关系数进行数据分析。研究结果表明,HIS高光谱成像系统重复性好,重复测量的平均色差为0.154;3种仪器测得的光谱反射率具有强相似性;相较于Spectravision多光谱成像系统,HIS高光谱成像系统的颜色结果更接近于分光光度计;Spectravision多光谱成像系统的有效像元尺寸更小,织物纹理对颜色结果影响较大,Spectravision多光谱成像系统测量的明度偏低;HIS高光谱成像系统的有效像元大小与相机工作距离成正比,适用范围更广。

In order to address the problem in color difference between spectrophotometry and spectral imaging when measuring the same fabric,Datacolor 600 spectrophotometer,Datacolor Spectravision and hyperspectral imaging system HIS were chosen to measure the same set of monochromatic cotton knitted fabrics.The reasons and mechanisms for the difference in color and in spectral reflectance measured by the three instruments were discussed.The color difference and spectral similarity between different instruments were calculated,and the data were analyzed by Pearson correlation coefficient method.The results show that HIS has good repeatability with the average color difference being 0.154.The spectral reflectance measured by the three instruments have strong similarity.Compared with Spectravision,the chromatic value of HIS is closer to the spectrophotometer.Spatial feature information is the main factor affecting the color and spectral reflectance.The pixel size of Spectravision are smaller,and Spectravision has a lower brightness due to the influence of shadow of yarns and fabric texture.The pixel size of HIS are proportional to the distance between the camera and the specimen,and HIS is applicable to a broader range.