Color depth

Color depth is either the number of bits used to indicate the color of a single pixel, in a bitmapped image or video frame buffer, or the number of bits used for each color component of a single pixel. For consumer video standards, such as High Efficiency Video Coding (H.265), the bit depth specifies the number of bits used for each color component. When referring to a pixel the concept can be defined as bits per pixel (bpp), which specifies the number of bits used. When referring to a color component the concept can be defined as bits per channel (bpc), bits per color (bpc), or bits per sample (bps). Color depth is only one aspect of color representation, expressing how finely levels of color can be expressed; the other aspect is how broad a range of colors can be expressed (the gamut). The definition of both color precision and gamut is accomplished with a color encoding specification which assigns a digital code value to a location in a color space.

Bit Depth

Bit depth is a value that describes the number of colours that an individual pixel can display. A bit can either be on or off. Therefore, a 1-bit pixel can display two colours: black and white. An 8-bit pixel displays 256 colours. Each bit can be on or off (2 states). When combined in eight different ways (2x2x2x2x2x2x2x2 or 28) it can display up to 256 colours.

Pixels are usually one of five standard bit-depths. Rarely is anything above 8 bits necessary.

Bits Per Pixel
Number of Colors Available Common Name(s)
2 Monochrome
16 EGA
256 VGA
65536 XGA, High Color
16777216 SVGA, True Color
16777216 + Transparency
281 Trillion



You may also like...