halfcolor

Halfcolor is a term used in digital imaging and computer graphics to describe a color-rendering approach in which every visible color is produced by blending two fixed base colors, rather than encoding colors across a full spectrum. The technique emphasizes a two-color basis, creating intermediate hues by interpolation between the two anchors. It is distinct from standard full-color representations and from printing halftones, although it can be used to simulate limited palettes or two-tone effects.

In typical implementations, the color of a pixel is computed by linear interpolation between the two anchor colors A and B according to a parameter t in the range [0,1]. The resulting color is often stored with a reduced color-depth, or rendered only at discrete steps, producing a drawable gradient with a limited palette. Some systems fix t to a set of predefined values to produce a small, controllable palette.

Variants of halfcolor appear in contexts such as duotone or two-color printing simulations, palette-limited art, or hardware that supports only two color channels. This approach can be applied to RGB spaces by pairing opposite corners (e.g., red and cyan) or by selecting two primaries that suit the display or print medium. Dithering can be used to mitigate banding in smooth gradients.

Limitations include a restricted color gamut, potential loss of luminance information, and nonstandard terminology that can hinder interoperability. Halfcolor is mainly a stylistic or resource-saving technique rather than a universal color model. Related concepts include color interpolation, duotone rendering, dithering, and palette reduction.