Explanation

Gamma encoding of images is appropriate to atone for backdrop of animal vision, to aerate the use of the $.25 or bandwidth about to how bodies apperceive ablaze and color.1 Animal eyes beneath accepted beam altitude (not angle atramentous or blindingly bright) follows an almost gamma or ability function. If images are not gamma encoded, they admeasure too abounding $.25 or too abundant bandwidth to highlights that bodies cannot differentiate, and too few bits/bandwidth to adumbration ethics that bodies are acute to and would crave added bits/bandwidth to advance the aforementioned beheld quality.12 Gamma encoding of amphibian point images is not appropriate (and may be counterproductive) because the amphibian point architecture already provides a pseudo-logarithmic encoding.

A accepted delusion is that gamma encoding was developed to atone for the input–output appropriate of cathode ray tube (CRT) displays.2 In CRT displays the electron-gun current, and appropriately ablaze intensity, varies nonlinearly with the activated anode voltage. Altering the ascribe arresting by gamma compression can abolish this nonlinearity, such that the achievement account has the advised luminance. However, the gamma characteristics of the affectation accessory do not play a agency in the gamma encoding of images and video — they charge gamma encoding to aerate the beheld superior of the signal, behindhand of the gamma characteristics of the affectation device.12 The affinity of CRT physics to the changed of gamma encoding bare for video manual was a aggregate of luck and engineering which simplified the electronics in aboriginal television sets.