Brightness and Contrast

In this topic, you will learn about, Brightness and Contrast.


Table of Contents

Brightness is a visual perception in which a source appears to be reflecting light. Brightness is a subjective property of an object which is being observed. Brightness is an absolute term and different from lightness.

A color screens use three colors i.e., RGB scheme (red, green and blue) the brightness of the screen depends upon the sum of the amplitude of red green and blue pixels, and it is divided by 3.

The perception of brightness depends upon the optical illusions to appear brighter or darker.

When the brightness is decreased, the color appears dull, and when brightness increases, the color is clearer.

In mobile devices, when the brightness setting is high, the device battery drains fast as compare to the low setting.


Contrast is a color that makes an object distinguishable. We can say that contrast is determined by the color and brightness of the object.

Contrast is the difference between the maximum and minimum pixel intensity of an image.

The formula of Contrast:
Contrast = maximum pixel intensity – minimum pixel intensity

For example:

Take the original image which has a matrix of As, we can see that the maximum value and minimum value of the pixel is 100.

According to formula

Contrast = 100 – 100 = 0

The answer is 0, which means the image has zero contrast.