gammaencoded

Gammaencoded describes data that has undergone gamma encoding, a nonlinear transfer used to approximate the response of display devices and human vision. The process transforms linear luminance values into a nonlinearly encoded form to improve perceptual uniformity and make efficient use of limited bit depth. In practice, gamma encoding is typically implemented as a power-law-like curve, and the inverse operation (gamma decoding) is applied by displays or rendering pipelines to recover linear light values.

Common display systems exhibit a gamma-like response, often around 2.2, which influences how data is encoded for storage or transmission. As a result, many workflows apply an exponent around 1/2.2 (approximately 0.45) during encoding so that decoding on the display yields a perceptually correct luminance. Some color spaces, such as sRGB, use a piecewise gamma-like function rather than a single power law, reflecting components for shadows and highlights.

Applications of gammaencoded data include digital photography, computer graphics textures, video, and image formats where perceptual nonlinearity is advantageous for quantization efficiency. Storing image data in gamma-encoded form can reduce banding and improve visual quality at fixed bit depths. However, gamma encoding is not a universal substitute for linear-light workflows; modern physically based rendering often operates in linear space and applies gamma correction only at display time or during output to target devices.

See also: gamma correction, sRGB, linear-light workflow, perceptual coding.