It is necessary to describe the gamut boundaries of the original and the reproduction properly for gamut mapping. It requires a thorough understanding of color reproduction gamut. Normally, the color values (CIELab) of different points are measured for describing the gamut boundary. For media gamut, it can be done by Kubelka-Munk equations and Neugebauer equation. In the present study, the gamut boundaries of the images are described considering color values of all pixels instead of measuring the CIELab values of sample points, which will minimize the approximation error. The out-of gamut colors are easily found in this way. It has been observed that the out-of-gamut color regions are not similar for different color zones. It has also been observed that the ratio of output gamut to input gamut are different for different images. Considering all these facts, an image-dependent gamut mapping is suggested in the present study.