Gamma correction,
gamma nonlinearity,
gamma encoding, or often simply
gamma, is the name of a nonlinear operation used to code and decode
luminance or
tristimulus values in
video or
still image systems. Gamma correction is, in the simplest cases, defined by the following
power-law expression:
![](http://info.babylon.com/onlinebox.cgi?rt=GetFile&uri=!!ARV6FUJ2JP&type=0&index=3924)