IRGB

Updated: 11/13/2018 by Computer Hope

Short for Intensity Red Green Blue, IRGB is a method of encoding sixteen unique colors in four bits. It is used in CGA and later video adapters in MS-DOS character mode. The four bits represent red, green, blue, and an intensity bit indicating an alternate brightness of the color combination. The sixteen possible colors created by IRGB encoding are listed in the following table.

Color name Bits
Intensity Red Green Blue
Black 0 0 0 0
Blue 0 0 0 1
Green 0 0 1 0
Cyan 0 0 1 1
Red 0 1 0 0
Magenta 0 1 0 1
Brown 0 1 1 0
Light gray 0 1 1 1
Dark gray 1 0 0 0
Light blue 1 0 0 1
Light green 1 0 1 0
Light cyan 1 0 1 1
Light red 1 1 0 0
Light magenta 1 1 0 1
Yellow 1 1 1 0
White 1 1 1 1

Color terms, Computer acronyms, Intensity bit, RGB, Video terms