Color Depth

Color depth is defined by the number of bits per pixel that can be displayed on a computer screen. Data is stored in bits. Each bit represents two colors because it either has a value of 0 or 1. The more bits per pixel, the more colors that can be displayed.

Determining Color Depth

Since each bit represents 2 colors, it is easy to work out the number of colors for the various color depths. The number of possible colors would be 2 to the power of the number of bits per pixel:

Monochrome

Monochrome is usually taken to mean the same as black-and-white or, more likely, grayscale, but may also be used to refer to other combinations containing only two colors, such as green-and-white or green-and-black.

A color depth of 1 bit would be 2 times itself 2 times:

2 x 1 x 1 = Monochrome (black and white or grayscale)

16 and 256 Colors

A color depth of 4 bits would be 2 times itself 4 times:

2 x 2 x 2 x 2 = 16 colors

A color depth of of 8 bits would be 2 times itself 8 times:

2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 = 256 colors

True Color

True Color exists when each pixel is defined in terms of its actual RGB or CMYK values. Every pixel in a true color image has 256 possible values for each of it's red, green or blue components (in the RGB model) or cyan, magenta, yellow and black (in the CMYK model).