The aim of this study was to explore methods for study of characteristics of pixel distributions of color images and methods for extraction of information of pixel reflection and diffusion, so as to offer theory basis of extraction of objective color appearance of the image. By combination of theoretical analysis and experiment verification, correlations between image intensity and illumination were analyzed, and objective characteristics of data distribution among diffuse chromaticity, pixel channel intensity and pixel overall intensity were clarified. Chromatic distribution of reflection pixels exhibited regular linear and hyperbolic characteristics, while diffusion distribution of pixels had only gathering characteristics unrelated to illumination. Pixel distribution patterns of reflection and diffusion are different for an image and their reflection information can be separated by straight lines with different slopes for RGB channels. Intrinsic color properties of both objects and illumination can be acquired successfully by incorporating a special transformation of pixel mapping.