1. A color processing method, comprising the steps of: calculating first boundary point data, which indicates a first boundary point of a source gamut in a line passing a sample point in the source gamut, and calculating a second boundary point of a destination gamut; calculating a color difference between the first and second boundary points on the basis of a visual characteristic; calculating a ratio between saturation of the sample point and saturation of the first boundary point data; and correcting the saturation of the sample point based on the color difference and the ratio to map the sample point into the destination gamut.