Computer Technology-based Color Space Conversion Model And Color Fastness Analysis System

Color fastness is a very important index to assess the quality of textiles. Currently the color fastness was received by specialist eyeballing. The results can be affected by some subjective factors. A conversion model between RGB and XYZ was builded to further establish a fabric color fansness analyzing system. This system that can analyze the pictures scanned tansforms the values of pictures in the RGB space into the valus in the XYZ space, and at last into the values in the Lab color space. Then the values in the Lab color space would be calculated to gain the chromatic aberration of textiles. Finally the grade of the color fastness would be assessed.Five parts were included in this paper. First part is about chromatology. The characteristics and relationships of RGB color space, XYZ color space and Lab color space were described. The second part is about the establishment of the conversion model. The conversion model between the RGB color space and the XYZ color space was builded with the data of the standard color card by matlab programme. In order to create system easily, a dynamic data-base was founded by matlab and vb mix-programme. In the third part the presentation of the chromatic aberration formulas were introduced. Four different formulas of CIE1974, FZ/T 01024-93, CMC, CIEDE2000 were showed. A new comparative system was built by four formulas to test 110 pieces of fabrics. The results were compared with the results received by specialist eyeballing. It showed that the results calculated by CMC was preciser than the ones gained by the national standards FZ/T 01024-93. so a brand-new system was built by using CMC. The establishment of the color fansness analyzing system was showed in the forth part. A fabric color fansness analyzing system was builded by vb programming. In the fifth part the presion of the color fansness analyzing system was tested. 255 change-color and 199 stain-color fabrics were tested by using the system. The testing results were compared with the results received by specialist eyeballing. The conclusion that the results gained by computer testing were nearly the same as the results gained by specialist eyeballing.The establishment of this testing system made up the bugs of specialist eyeballing, such as low testing efficiency and huge fluctuation of the results. The practicality of this system is good. It fill up the blankness of domestic similar products and softwares.