Texture Effect On Visual Color Difference Evaluation

An image is consisted of color and texture, the different textures of images would affect the visual color difference significantly when the colors of the images are the same or familiar. Especially in the textile industry, the texture structure significantly affects the magnitude of visual color difference between textuRED color samples. The fundamental objective of this investigation is to establish the mathematical model between the visual color difference and texture structure. We attempt to thoroughly investigate this texture effect for color pairs with either identical or different texture structures.In our experiment,12 textiles in 5 color centers recommended by the CIELAB were selected. The textuRED color images were generated by using the color-mapping technique, and displayed on a calibrated CRT monitor in the visual experiment. The texture effects in all three color directions (i.e., lightness, hue, and chroma) were analyzed on a large set of color samples including variations in five color centers, twelve texture structures, and three color difference grades. The content of the experiment include both contrasts between the same and the different textiles.63 observers without visual problem are invited to finish the experiment in the same environment with the gray scale method which is used frequently in visual tests.In this thesis, we discuss the effective texture features extracted from texture images and their correlations with the evaluated visual color difference on sample pairs with identical texture structure, and a new formula of texture textile degree is given which consisted of several textile characters. Three formulas are achieved under different color difference degrees to connect the color difference of the textiles and the visual color differences. It was observed that, under the qualitative sense, a simple combination of several texture features yields a quite high correlation on the whole trends. To derive the generic mathematical model for individual color pairs, it seems necessary to extract texture features that are more descriptive to color difference perception.