The Gamma value in the display uses a mathematical method based on a power function. Specifically, Gamma correction describes the nonlinear relationship between the input signal (such as voltage or digital signal strength) and the output brightness of the display.
This relationship is usually expressed by a power function, that is, the output brightness is a function of the Gamma power of the input signal strength.
Mathematically, this relationship can be expressed as:
Lout =Linγ
Where:
Lout is the output brightness of the display.
Lin is the input signal strength (which can be voltage, digital value, etc.), which is usually normalized to a range of 0 to 1.
γ is the Gamma value, which is a real number greater than 0 and is used to describe the nonlinear relationship between input and output.
In practical applications, since the human eye's perception of brightness is nonlinear, Gamma correction is used to compensate for this nonlinearity, making the image displayed on the display closer to the brightness actually felt by the human eye. By adjusting the Gamma value, the grayscale brightness value of the middle tone of the image can be changed, thereby optimizing the details and layering of the image.
It is worth noting that although gamma correction is usually described based on a power function, in some cases, in order to more accurately match the perceptual characteristics of the human eye or meet specific display requirements, a more complex mathematical model or lookup table (LUT) may be used to implement gamma correction.
However, the power function model has been widely used in many applications due to its simplicity and effectiveness.