Gamma

 Gamma

• Gamma is the way that Luminance is displayed on a screen

• Gamma is non linear, meaning the voltage applied to cause the luminance to increase of decrease is follows a curve:

• Gamma correction is adjusting the colour information to match the gamma characteristics.

• gamma encoding was developed originally to compensate for the input–output characteristic of cathode ray tube (CRT) displays

• Gamma encoding of images is used to optimised the usage of data when encoding an image. By taking advantage of the non-linear manner in which humans perceive light and colour.

• If images are not gamma-encoded, they allocate too much data to highlights that humans cannot differentiate, and too little data to shadow values that humans are sensitive to and would require more data to maintain the same visual quality.