1. A method of transforming device-dependent color values in a device-dependent color space of a color input device to device-independent color values inside a human visual gamut in a device-independent color space, comprising the steps of: providing a mathematical model for converting device-dependent color values in a device-dependent color space of the color input device to device-independent color values in the device-independent color space; converting an input device-dependent color value in the device-dependent color space generated by the color input device into a device-independent color value in the device-independent color space using the mathematical model; determining, using a processor, whether or not the device-independent color value has a luminance component less than zero; when it is determined that the luminance component is less than zero, performing the following steps: clipping the luminance component to zero; and setting chromaticity components of the device-independent color value to zero; and when it is determined that the luminance component is not less than zero, performing the following steps: determining whether or not the device-independent color value is outside the human visual gamut in the device-independent color space; and when it is determined that the device-independent color value is outside the human visual gamut, clipping the device-independent color value to another device-independent color value in the device-independent color space on a boundary of the human visual gamut wherein the boundary of the human visual gamut corresponds to the CIE spectral locus on a chromaticity space.