color depth(redirected from 4-bit colour)
color depthThe number of bits used to hold a screen pixel. Also called "pixel depth" and "bit depth," the color depth is the maximum number of colors that can be displayed. True Color (24-bit color) is required for photorealistic images and video, and modern graphics cards support this bit depth.
Per Pixel or Per Subpixel
The color depth of a screen can be referenced by the number of bits in each subpixel or by the total number of bits per pixel. For example, 8-bit color and 24-bit color can mean the same system. The 8-bits refers to each red, green and blue subpixel, while the 24-bit means all three subpixels. Likewise, 10-bit color (subpixels) and 30-bit color (pixels) are the same. See indexed color and bit depth.
Bits Per Pixel Total Colors 4 16 (Standard VGA) 8 256 (Super VGA, indexed color) 15 32K (option on earlier cards) 16 65K (High Color) 24 16M (True Color) 32 16M (True Color + alpha channel) 30 1B (Deep Color) 36 68B (Deep Color) 48 260T (Deep Color)