Color Naming System

From Wikipedia, the free encyclopedia
Jump to: navigation, search

The Color Naming System (CNS) is a systematic notation for named colors for computer applications using English terms created by Berk et al. in 1982.[1]

System[edit]

CNS uses ten color names, three of which (black, white, gray) are special, and has them combined or prefixed with several modifiers.

The system expressed in Backus–Naur Form looks something like this:.[2][3]

named-color     := gray-color | chromatic-color
 
gray-color      := 'black' | 'white' | lightness gray
gray            := 'gray' | 'grey'
 
chromatic-color := [ tint | shade ] hue | [ lightness || saturation ]? hue
tint            := 'whitish' | 'pale' | 'brilliant' | 'vivid'
shade           := 'blackish' | 'dim' | 'deep' | 'vivid'
saturation      := 'grayish' | 'moderate' | 'strong' | 'vivid'
lightness       := 'moderate' | 'very'? [ 'dark' | 'light' ]
hue             := splash-color? base-color | base-color '-' base-color
base-color      := 'red' | 'orange' | 'brown' | 'yellow' | 'green' | 'blue' | 'purple'
splash-color    := 'reddish' | 'orangish' | 'brownish' | 'yellowish' | 'greenish' | 'bluish' | 'purplish'

Derivations[edit]

There have been variations of the CNS proposed for inclusion into CSS that are more compatible with existing schemes.[4]

color            := [saturation || lightness || transparency] hue
 
saturation       := absolute saturation-value | saturation-value relative
saturation-value := 'dull' | 'bright'
lightness        := absolute lightness-value | lightness-value relative
lightness-value  := 'dark' | 'light'
absolute         := [modifier '-']?
modifier         := 'extra' | 'semi'
relative         := 'er'
 
transparency     := ['semi-']? opacity-value
opacity-value    := 'opaque' | 'transparent'
 
hue              := prime | general | special
prime            := 'red' | 'green' | 'blue' | 'cyan' | 'magenta' | 'yellow' | 'white' | 'black'
general          := 'navy' | 'lime' | 'teal' | 'aqua' | 'maroon' | 'purple' | 'fuchsia' | 'olive' | 'gray' | 'silver'
special          := extra | composite   ;   composite ≈ prime '-' prime
extra            := 'pink' | 'brown' | 'tan' | 'orange'
composite        := 'yellow-green' | 'green-cyan' | 'cyan-blue' | 'blue-magenta' | 'magenta-red' |

References[edit]

  1. ^ Berk; Brownston; Kaufman (1982). "A New Color-Namiing System for Graphics Languages". IEEE Computer Graphics and Applications 2 (3): 37. doi:10.1109/MCG.1982.1674223.  edit
  2. ^ Tab Atkins Jr.: The CNS Color Naming System on adding CNS to CSS Color level 4
  3. ^ "CNS". Crissov. Retrieved 1 August 2013. 
  4. ^ Benjamin D. Gray (May 2002). "New CSS3 Color Names".