The cross-section of the polyester filament yarn has been modified to have a variety of shape for aesthetic, added functions and sensitivities, and other purposes. Transparent polyester filament of trilobal cross-section has unique optical properties with high anisotropic reflectivity and transmissivity. The monofilament yarns may be utilized to impart to the fabrics lustrous appearance along with unique color change in case differently dyed yarns are woven together. The color changes of the fabric specimens according to the changes in observation and lighting conditions were analyzed using a CCD camera and an image analysis software. The changes of color/luster of the fabric specimens were measured and analyzed based on RGB, $L^*a^*b^*,;L^*C^*h,$ and the color distribution within a three-dimensional color space.