Standardized RGB-spaces such as sRGB, Adobe RGB and etc. are common for image processing. Those spaces are non-linear (e.g. using gamma correction), so color calculations in such spaces are incorrect from a physical (colorimetric) point of view. Use of the linearized RGB space is proposed for adjusting the saturation.

A method for calculating the saturation employed in HSL and HSB color spaces (color models) is based solely on geometric considerations and does not provide a strict justification. The paper proposes a method for modifying the saturation leaving the lightness and color hue unchanged, which is correct from colorimetrical perspective. Proposed formulas do not require orthogonal RGB spaces. A concept of relative saturation is introduced.

An algorithm for maximizing digital image saturation is proposed. The linear saturation of image pixels is increased by the same factor without moving out of RGB-space gamut. The algorithm is implemented in C3C Color Wizard software that is the only implementation currently known to the author.

An algorithm for saturation limitation followed by contrast increase is proposed on the basis of P. Kosenko's approach. The algorithm allows harmonizing visual perception of digital photography in some cases.