RGBRHSL

RGBRHSL is a hybrid color representation used in some graphics pipelines that combines the standard RGB color triplet with an RHSL descriptor to allow both device-accurate color rendering and perceptual color editing within a single value. In practice, an RGBRHSL color consists of a conventional RGB component used for display and an accompanying RHSL component that encodes perceptual attributes. The RHSL portion is conceptually similar to an HSL model but anchored to a reference color around red; its parameters typically include hue, saturation, and lightness, expressed in normalized ranges. The exact encoding and channel layout vary by implementation; some systems store RGB as eight-bit or floating-point values and attach a parallel set of RHSL values, while others pack all related values into a single structure.

Processing and conversion: When rendering, the display engine converts the color to a pure RGB value suitable for the target device, commonly by applying the RHSL adjustments to the base RGB color or by translating the RHSL descriptor into a perceptual adjustment before combining with RGB. Editing workflows often manipulate the RHSL component for perceptual corrections and then re-export to RGB for rendering. Gamut handling is needed, as RHSL edits can push colors outside the device gamut.

Applications and considerations: RGBRHSL can simplify pipelines that require perceptual adjustments without losing device fidelity, support color grading and accessibility workflows, and enable consistent hue shifts across lighting conditions. However, it introduces additional storage, processing complexity, and interoperability challenges, since there is no universal standard for the RHSL encoding.