Color Depth

Color depth is a computer graphics term describing the number of bits used to represent the color of a single pixel in a bitmapped image or video frame buffer. This concept is also known as bits per pixel (bpp), particularly when specified along with the number of bits used. Higher color depth gives a broader range of distinct colors.

Indexed color

With relatively low color depth, the stored value is typically an index into a color map or palette. The colors available in the palette itself may be fixed by the hardware or modifiable.
  • 1-bit color (21 = 2 colors) monochrome, often black and white
  • 2-bit color (22 = 4 colors) CGA
  • 4-bit color (24 = 16 colors) as used by the least common denominator VGA standard
  • 8-bit color (28 = 256 colors) Super VGA

Direct color

As the number of bits increases, the number of possible colors becomes impractically large for a color map. In higher color depths, the color value typically directly encodes relative brightnesses of red, green, and blue to specify a color in the RGB color model.

HiColor

HiColor or Highcolor is considered sufficient to provide life-like colors, and is encoded using either 15 or 16 bits:
  • 15-bit color uses 5 bits to represent red, 5 bits to represent blue, and 5 bits to represent green. 25 = 32 levels of each of these three colour can therefore be combined to give a total of 32,768 mixed colours (32 x 32 x 32 = 32,768)
  • 16-bit color uses 5 bits to represent red, 5 bits to represent blue, but (since the human eye is more sensitive to the color) uses 6 bits to represent 64 levels of green. These can therefore be combined to give 65,536 mixed colours (32 x 32 x 64 = 65,536)

Truecolor

Truecolor can frequently mimic many colors found in the real world, producing 16.7 million distinct colors. This approaches the level at which the human eye can distinguish colors for most photographic images, though image manipulation or "pure" generated images may reveal the limitations.
  • 24-bit Truecolor uses 8 bits to represent red, 8 bits to represent blue, and 8 bits to represent green. 28 = 256 levels of each of these three colour can therefore be combined to give a total of 16,777,216 mixed colours (256 x 256 x 256).

32-bit color

"32-bit color" is a misnomer when regarding display color depth. Many assume that 32-bit color produces 4,294,967,296 distinct colors. In reality, 32-bit color actually refers to 24-bit color (Truecolor) with an additional 8 bits either as empty padding space or to represent an alpha channel.

Selection of color depth

In graphics intensive applications such as computer games, a tradeoff of performance and quality can be achieved by raising or lowering the color depth of the display; graphics with lower color depths do not require as much frame buffer memory or display bandwidth, allowing them to be generated and displayed more quickly. Increasing color depth results in higher color quality at the expense of display speed and responsiveness.

 

<< PreviousWord BrowserNext >>
car numberplate game
commodore records
anja andersen
vee jay records
jan pieterszoon sweelinck
valley records
car cricket
true tone records
cirencester grammar school
jiva
united records
six flags la ronde
centre party
jat airways
johann ludwig bach
acharya tulsi
afro dite
melodifestivalen
geoffrey davis
theobald smith
saunders roe princess
united states department of agriculture foreign agricultural service
albert ammons
pete johnson
sushil kumarji
alfalfa leafcutter bee
oyster pirate
yellow peril
deke slayton
philipp i of hesse
bowie knife
wally schirra
albacore
chinese characters of empress wu
reliant energy
yamagata, gifu
honam line
honam expressway
dilligaff
evil reptilian kitten eater from another planet
val d'aosta
dazz band
old regular baptist
mealy machine