Gamut Mapping

Gamut mapping is a technique used in color management to transform colors from one color space to another. It is used to ensure that colors are accurately reproduced across different devices and media, taking into account the limitations of each device’s color gamut.

Definition

A color gamut is the range of colors that a device or medium can produce. It is typically represented as a three-dimensional shape in color space, with the axes representing the different color components (e.g. red, green, and blue).

Why is Gamut Mapping Needed?

Gamut mapping is needed because different devices and media have different color gamuts. For example:

• Monitors: Monitors have a limited color gamut, typically around 70-80% of the visible color spectrum.
• Printers: Printers have a limited color gamut, typically around 50-60% of the visible color spectrum.
• Digital Cameras: Digital cameras have a wider color gamut, typically around 90-100% of the visible color spectrum. When colors are transferred between devices or media, they may not be accurately reproduced due to the differences in color gamut. Gamut mapping helps to ensure that colors are accurately reproduced by transforming them to fit within the target device’s color gamut.

Types of Gamut Mapping

There are several types of gamut mapping, including:

• Hard Clipping: Hard clipping involves clipping colors that are outside the target gamut to the nearest color within the gamut.
• Soft Clipping: Soft clipping involves gradually adjusting colors that are outside the target gamut to fit within the gamut.
• Color Constancy: Color constancy involves adjusting colors to maintain their perceived color appearance, rather than their exact color values.

Techniques

• Linear Gamut Mapping: Linear gamut mapping involves transforming colors using a linear transformation.
• Non-Linear Gamut Mapping: Non-linear gamut mapping involves transforming colors using a non-linear transformation.
• Gamut Mapping using Color Appearance Models: Gamut mapping using color appearance models involves using models of color appearance to transform colors.