chromatic library

A comprehensive color science library for Dart.

Provides color space conversions, perceptual color difference (Delta E), chromatic adaptation, and more.

import 'package:chromatic/chromatic.dart';

final red = SRgbColor(1.0, 0.0, 0.0);
final lab = red.toLab();
print(lab); // Lab(53.23, 80.11, 67.22)

final other = LabColor(50, 30, -20);
print(deltaE00(lab, other)); // perceptual distance

Classes

AdobeRgbColor

Adobe RGB (1998) color.

AppleRgbColor

Apple RGB color.

BaseRgbColor

Base class for RGB color spaces.

Bt2020Color

ITU-R BT.2020 color.

CmyColor

CMY (Cyan, Magenta, Yellow) color.

CmykColor

CMYK (Cyan, Magenta, Yellow, Key/Black) color.

ColorBase

Base class for all color types.

HslColor

HSL (Hue, Saturation, Lightness) color.

HsvColor

HSV (Hue, Saturation, Value) color.

IptColor

IPT color space (Image Processing Transform).

LabColor

CIE Lab* color.

LchAbColor

CIE LCH(ab) color — cylindrical form of Lab.

LchUvColor

CIE LCH(uv) color — cylindrical form of Luv.

LuvColor

CIE Luv* color.

RgbColorSpaceDef

Defines the properties of an RGB color space.

SRgbColor

sRGB color (IEC 61966-2-1).

XyyColor

CIE 1931 xyY chromaticity color.

XyzColor

CIE 1931 XYZ color.

Constants

adaptationMatrices → const Map<String, List<double>>

3x3 adaptation matrices as flat row-major lists.

adobeRgbDef → const RgbColorSpaceDef

Adobe RGB (1998).

appleRgbDef → const RgbColorSpaceDef

Apple RGB.

bt2020Def → const RgbColorSpaceDef

ITU-R BT.2020.

cieE → const double

CIE epsilon: 216/24389 ≈ 0.008856

cieK → const double

CIE kappa: 24389/27 ≈ 903.3

illuminants → const Map<String, Map<String, List<double>>>

Standard illuminant white-point XYZ values.

sRgbDef → const RgbColorSpaceDef

sRGB color space (IEC 61966-2-1).

Functions

adaptXyzColor(XyzColor color, {required String targetIlluminant, String method = 'bradford'}) → XyzColor

Adapts an XyzColor to a new illuminant, returning a new XyzColor.

chromaticAdapt(double x, double y, double z, {required String sourceIlluminant, required String targetIlluminant, String observer = '2', String method = 'bradford'}) → (double, double, double)

Applies chromatic adaptation to XYZ values.

cmykToCmy(CmykColor cmyk) → CmyColor

Converts CmykColor to CmyColor.

cmyToCmyk(CmyColor cmy) → CmykColor

Converts CmyColor to CmykColor.

cmyToRgb(CmyColor cmy) → SRgbColor

Converts CmyColor to SRgbColor.

deltaE00(LabColor c1, LabColor c2, {double kL = 1, double kC = 1, double kH = 1}) → double

CIEDE2000 color difference — the gold standard.

deltaE76(LabColor c1, LabColor c2) → double

CIE76 color difference — simple Euclidean distance in Lab.

deltaE94(LabColor c1, LabColor c2, {double kL = 1, double kC = 1, double kH = 1, double k1 = 0.045, double k2 = 0.015}) → double

CIE94 color difference.

deltaECmc(LabColor c1, LabColor c2, {double pl = 2, double pc = 1}) → double

CMC l:c color difference.

hslToRgb(HslColor hsl) → SRgbColor

Converts HslColor to SRgbColor.

hsvToRgb(HsvColor hsv) → SRgbColor

Converts HsvColor to SRgbColor.

iptToXyz(IptColor ipt) → XyzColor

Converts IptColor to XyzColor.

labToLchAb(LabColor lab) → LchAbColor

Converts LabColor to LchAbColor.

labToSRgb(LabColor lab) → SRgbColor

Converts LabColor directly to SRgbColor.

labToXyz(LabColor lab) → XyzColor

Converts LabColor to XyzColor.

lchAbToLab(LchAbColor lch) → LabColor

Converts LchAbColor to LabColor.

lchAbToSRgb(LchAbColor lch) → SRgbColor

Converts LchAbColor directly to SRgbColor.

lchUvToLuv(LchUvColor lch) → LuvColor

Converts LchUvColor to LuvColor.

luvToLchUv(LuvColor luv) → LchUvColor

Converts LuvColor to LchUvColor.

luvToXyz(LuvColor luv) → XyzColor

Converts LuvColor to XyzColor.

rgbToCmy(BaseRgbColor rgb) → CmyColor

Converts BaseRgbColor to CmyColor.

rgbToHsl(BaseRgbColor rgb) → HslColor

Converts SRgbColor to HslColor.

rgbToHsv(BaseRgbColor rgb) → HsvColor

Converts SRgbColor to HsvColor.

rgbToXyz(BaseRgbColor rgb, {String? targetIlluminant, String observer = '2'}) → XyzColor

Converts an BaseRgbColor to XyzColor.

sRgbToHsl(SRgbColor rgb) → HslColor

Converts SRgbColor directly to HslColor.

sRgbToHsv(SRgbColor rgb) → HsvColor

Converts SRgbColor directly to HsvColor.

sRgbToLab(SRgbColor rgb, {String? illuminant, String observer = '2'}) → LabColor

Converts SRgbColor directly to LabColor.

sRgbToLchAb(SRgbColor rgb, {String? illuminant, String observer = '2'}) → LchAbColor

Converts SRgbColor directly to LchAbColor.

xyyToXyz(XyyColor xyy) → XyzColor

Converts XyyColor to XyzColor.

xyzToAdobeRgb(XyzColor xyz) → AdobeRgbColor

Converts XyzColor to AdobeRgbColor.

xyzToAppleRgb(XyzColor xyz) → AppleRgbColor

Converts XyzColor to AppleRgbColor.

xyzToBt2020(XyzColor xyz) → Bt2020Color

Converts XyzColor to Bt2020Color.

xyzToIpt(XyzColor xyz) → IptColor

Converts XyzColor to IptColor. Requires D65 illuminant.

xyzToLab(XyzColor xyz) → LabColor

Converts XyzColor to LabColor.

xyzToLuv(XyzColor xyz) → LuvColor

Converts XyzColor to LuvColor.

xyzToSRgb(XyzColor xyz) → SRgbColor

Converts XyzColor to SRgbColor.

xyzToXyy(XyzColor xyz) → XyyColor

Converts XyzColor to XyyColor.