net.returnvoid.color

Class LabColor

java.lang.Object

net.returnvoid.color.LabColor

All Implemented Interfaces:

RColor

public class LabColor
extends java.lang.Object
implements RColor

A model for color in Lab color space. A LabColor can be converted to any other color model. To use this in Processing use the getColor() Method:

 fill(myLabObject.getColor());
 

The difference between multiple color objects can be calculated with the methods of ColorDifference class.
The ranges of the values are not bounded. The following values just give an approximation of the ranges.

L = Luminance [0, 100] = [LabColor.MIN_L, LabColor.MAX_L]
a ~ [-86, 98] = [LabColor.MIN_A, LabColor.MAX_A]
b ~ [-107.6, 94.6] = [LabColor.MIN_B, LabColor.MAX_B]
Alpha = transparency [0, 100]

Author:

Diana Lange

Field Summary

Fields

Modifier and Type	Field and Description
static float	MAX_A The maximal a value any Lab color can have (approximation).
static float	MAX_B The maximal b value any Lab color can have (approximation).
static float	MAX_L The maximal luminance value any Lab color can have.
static float	MIN_A The minimal a value any Lab color can have (approximation).
static float	MIN_B The minimal b value any Lab color can have (approximation).
static float	MIN_L The minimal luminance value any Lab color can have.
static ColorSpace	NAME The ColorSpace of RGB colors.

Constructor Summary

Constructors

Constructor and Description
LabColor(float... channels) Creates a new LabColor object.
LabColor(java.lang.Float l, java.lang.Float a, java.lang.Float b) Creates a new opaque LabColor object.
LabColor(java.lang.Float l, java.lang.Float a, java.lang.Float b, java.lang.Float alpha) Creates a new LabColor object.

Method Summary

Modifier and Type	Method and Description
LabColor	copy() Creates a deep copy of the object.
boolean	equals(RColor other) Checks if the input color is equal to this object.
java.lang.Float	getA() Returns the current value of a of this color.
java.lang.Float	getAlpha() Returns the value of alpha / transparency.
java.lang.Float	getB() Returns the current value of b of this color.
java.lang.Float	getChroma() Returns the current value of chroma of this color (equivalent to the chroma value of this color's LCH conversion).
static float	getChroma(java.lang.Float a, java.lang.Float b) Calculates the chroma value of a given set of a and b values.
int	getColor() Returns a int representation of the current color.
ColorSpace	getColorSpace() Returns the color space of the color.
java.lang.String	getHexString() Returns a String representation of the current color using hexadecimal numbers.
java.lang.Float	getHue() Returns the current value of hue of this color (equivalent to the hue value of this color's LCH conversion).
static float	getHue(double a, double b) Calculates the hue value of a given set of a and b values.
static java.lang.Float	getLoss(RColor rvMean, java.util.ArrayList<RColor> lColors, ColorDifferenceMeasure m) Calculates the loss - the mean distance of all members of colors to rvMean.
static java.lang.Float	getLoss(RColor rvMean, java.util.ArrayList<RColor> lColors, ColorDifferenceMeasure m, int start, int end) Calculates the loss - the mean distance of all members of colors to rvMean.
static java.lang.Float	getLoss(RColor rvMean, RColor[] colors, ColorDifferenceMeasure m) Calculates the loss - the mean distance of all members of colors to rvMean.
static java.lang.Float	getLoss(RColor rvMean, RColor[] colors, ColorDifferenceMeasure m, int start, int end) Calculates the loss - the mean distance of all members of colors to rvMean.
float	getLuminance() Returns the current value of luminance of this color.
static LabColor	getMeanColor(java.util.ArrayList<RColor> colors) Calculates the mean color of the input colors
static LabColor	getMeanColor(int start, int end, java.util.ArrayList<RColor> colors) Calculates the mean color of the input colors.
static LabColor	getMeanColor(int start, int end, RColor... colors) Calculates the mean color of the input colors.
static LabColor	getMeanColor(RColor... colors) Calculates the mean color of the input colors
java.lang.String	getName() Returns the name of the color space e.g.
int	getOpColor() Returns a int representation of the current color - but ignoring the alpha value.
java.lang.String	getOpHexString() Returns a String representation of the current color using hexadecimal numbers.
static LabColor	getRandomLab() Creates a new opaque LabColor with random values.
float[]	getValues() Returns the color values of the current object.
float[]	getValuesNormalized() Returns the normalized color values of the current object.
static LabColor	lerpColors(RColor input1, RColor input2, float amt) Lerps the two input colors and creates a new color.
LabColor	setA(java.lang.Float a) Sets the a value.
LabColor	setA(int a) Sets the a value.
LabColor	setAlpha(java.lang.Float alpha) Sets the value of alpha / transparency.
LabColor	setAlpha(int alpha) Sets the value of alpha / transparency.
LabColor	setB(java.lang.Float b) Sets the b value.
LabColor	setB(int b) Sets the b value.
LabColor	setLuminance(java.lang.Float l) Sets the luminance value.
LabColor	setLuminance(int l) Sets the luminance value.
HSBColor	toHSB() Returns a HSBColor representation of the current color.
LabColor	toLab() Returns a LabColor representation of the current color.
LCHColor	toLCH() Returns a LCHColor representation of the current color.
RGBColor	toRGB() Returns a RGBColor representation of the current color.
java.lang.String	toString()
XYZColor	toXYZ() Returns a XYZColor representation of the current color.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

NAME

public static final ColorSpace NAME

The ColorSpace of RGB colors.

MIN_L

public static final float MIN_L

The minimal luminance value any Lab color can have.

See Also:

Constant Field Values

MAX_L

public static final float MAX_L

The maximal luminance value any Lab color can have.

See Also:

Constant Field Values

MIN_A

public static final float MIN_A

The minimal a value any Lab color can have (approximation).

See Also:

Constant Field Values

MAX_A

public static final float MAX_A

The maximal a value any Lab color can have (approximation).

See Also:

Constant Field Values

MIN_B

public static final float MIN_B

The minimal b value any Lab color can have (approximation).

See Also:

Constant Field Values

MAX_B

public static final float MAX_B

The maximal b value any Lab color can have (approximation).

See Also:

Constant Field Values

Constructor Detail

LabColor

public LabColor(java.lang.Float l,
                java.lang.Float a,
                java.lang.Float b)

Creates a new opaque LabColor object. The input values will be constrained to the valid range of Lab.

Parameters:

l - The luminance value [0, 100]

a - The a value [-86, 98]

b - The b value [-107.6, 94.6]

LabColor

public LabColor(java.lang.Float l,
                java.lang.Float a,
                java.lang.Float b,
                java.lang.Float alpha)

Creates a new LabColor object. The input values will be constrained to the valid range of Lab.

Parameters:

l - The luminance value [0, 100]

a - The a value [-86, 98]

b - The b value [-107.6, 94.6]

alpha - THe alpha value [0, 100]

LabColor

public LabColor(float... channels)

Creates a new LabColor object. The input values will be constrained to the valid range of LabColor.

Parameters:

channels - Either [l, a, b] or [l, a, b, alpha].

Method Detail

getColor

public int getColor()

Description copied from interface: RColor

Returns a int representation of the current color. The range will be between 0xFFFFFFFF and 0x00000000. Using this, the color object can be used to set the color within Processing. Example:

 HSBColor hsb = new HSBColor(244, 100, 100);
 fill(hsb.getColor());
 

Specified by:

getColor in interface RColor

Returns:

the color value of the object.

setAlpha

public LabColor setAlpha(java.lang.Float alpha)

Description copied from interface: RColor

Sets the value of alpha / transparency. The range of alpha depends on the model of the color space. For RGB alpha will have a range of [0, 255]. For all other color spaces the range is [0, 100]. Zero always means that the color is completely transparent. The high value means that the color is completely opaque.

Specified by:

setAlpha in interface RColor

Parameters:

alpha - The value of the colors transparency.

Returns:

The current color object.

setAlpha

public LabColor setAlpha(int alpha)

Sets the value of alpha / transparency. The range of alpha is [0, 100]. Zero always means that the color is completely transparent. The high value means that the color is completely opaque.

Parameters:

alpha - The value of the colors transparency.

Returns:

The current color object.

getAlpha

public java.lang.Float getAlpha()

Description copied from interface: RColor

Returns the value of alpha / transparency. The range of alpha depends on the model of the color space. For RGB alpah will have a range of [0, 255]. For all other color spaces the range is [0, 100]. Zero always means that the color is completely transparent. The high value means that the color is completely opaque.

Specified by:

getAlpha in interface RColor

Returns:

The value of transparency.

setLuminance

public LabColor setLuminance(java.lang.Float l)

Sets the luminance value. The input value will be constrained to the valid range of Lab.

Parameters:

l - The new luminance value [0, 100].

Returns:

The current LabColor object.

setLuminance

public LabColor setLuminance(int l)

Sets the luminance value. The input value will be constrained to the valid range of Lab.

Parameters:

l - The new luminance value [0, 100].

Returns:

The current LabColor object.

setA

public LabColor setA(java.lang.Float a)

Sets the a value. The input value will be constrained to the valid range of Lab.

Parameters:

a - The new a value [-86, 98].

Returns:

The current LabColor object.

setA

public LabColor setA(int a)

Sets the a value. The input value will be constrained to the valid range of Lab.

Parameters:

a - The new a value [-86, 98].

Returns:

The current LabColor object.

setB

public LabColor setB(java.lang.Float b)

Sets the b value. The input value will be constrained to the valid range of Lab.

Parameters:

b - The new a value [-107.6, 94.6].

Returns:

The current LabColor object.

setB

public LabColor setB(int b)

Sets the b value. The input value will be constrained to the valid range of Lab.

Parameters:

b - The new a value [-107.6, 94.6].

Returns:

The current LabColor object.

getLuminance

public float getLuminance()

Returns the current value of luminance of this color.

Returns:

The luminance of this color.

getA

public java.lang.Float getA()

Returns the current value of a of this color.

Returns:

The a of this color.

getB

public java.lang.Float getB()

Returns the current value of b of this color.

Returns:

The b of this color.

getChroma

public java.lang.Float getChroma()

Returns the current value of chroma of this color (equivalent to the chroma value of this color's LCH conversion).

Returns:

The chroma of this color.

getHue

public java.lang.Float getHue()

Returns the current value of hue of this color (equivalent to the hue value of this color's LCH conversion).

Returns:

The chroma of this color.

getHexString

public java.lang.String getHexString()

Description copied from interface: RColor

Returns a String representation of the current color using hexadecimal numbers. The range will be between "FFFFFFFF" and "00000000". Example:

 RGBColor rgb = new RGBColor(255, 0, 128, 0);
 rgb.getHexString(); // "00FF0080"
 

Specified by:

getHexString in interface RColor

Returns:

the color value of the object.

getOpColor

public int getOpColor()

Description copied from interface: RColor

Returns a int representation of the current color - but ignoring the alpha value. The output will always be opaque ('Op' in method name stands for Opaque). The range will be between 0xFFFFFFFF and 0xFF000000. Using this, the color object can be used to set the color within Processing. Example:

 HSBColor hsb = new HSBColor(244, 100, 100, 50);
 fill(hsb.getOpColor());
 

Specified by:

getOpColor in interface RColor

Returns:

the color value of the object.

getOpHexString

public java.lang.String getOpHexString()

Description copied from interface: RColor

Returns a String representation of the current color using hexadecimal numbers. The alpha value will be ignored ('Op' in method name stands for Opaque). The range will be between "FFFFFF" and "000000". Example:

 RGBColor rgb = new RGBColor(255, 0, 128, 0);
 rgb.getOpHexString(); // "FF0080"
 

Specified by:

getOpHexString in interface RColor

Returns:

the color value of the object.

getValues

public float[] getValues()

Description copied from interface: RColor

Returns the color values of the current object. Depending on the color space these are:
[0] = red [1] = green [2] = blue [3] = alpha
[0] = hue [1] = saturation [2] = brightness [3] = alpha
[0] = x [1] = y [2] = z [3] = alpha
[0] = L [1] = a [2] = b [3] = alpha
[0] = L [1] = C [2] = Hue [3] = alpha

Specified by:

getValues in interface RColor

Returns:

the colors.

getValuesNormalized

public float[] getValuesNormalized()

Description copied from interface: RColor

Returns the normalized color values of the current object. The ranges of all values will be between [0,1]. Depending on the color space the values are:
[0] = red [1] = green [2] = blue [3] = alpha
[0] = hue [1] = saturation [2] = brightness [3] = alpha
[0] = x [1] = y [2] = z [3] = alpha
[0] = L [1] = a [2] = b [3] = alpha
[0] = L [1] = C [2] = Hue [3] = alpha

Specified by:

getValuesNormalized in interface RColor

Returns:

the colors.

getName

public java.lang.String getName()

Description copied from interface: RColor

Returns the name of the color space e.g. "RGBColor"

Specified by:

getName in interface RColor

Returns:

The name of the color space.

getColorSpace

public ColorSpace getColorSpace()

Description copied from interface: RColor

Returns the color space of the color.

Specified by:

getColorSpace in interface RColor

Returns:

The color space.

copy

public LabColor copy()

Description copied from interface: RColor

Creates a deep copy of the object.

Specified by:

copy in interface RColor

Returns:

The copied object.

equals

public boolean equals(RColor other)

Checks if the input color is equal to this object. Two colors are equal if they are member of the same color space and all channel values are equal.

Specified by:

equals in interface RColor

Parameters:

other - The other color

Returns:

True if both colors are considered the same;

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getMeanColor

public static LabColor getMeanColor(RColor... colors)

Calculates the mean color of the input colors

Parameters:

colors - Colors (1 or more).

Returns:

The new LabColor object that represents the mean color.

getMeanColor

public static LabColor getMeanColor(java.util.ArrayList<RColor> colors)

Calculates the mean color of the input colors

Parameters:

colors - Colors.

Returns:

The new LabColor object that represents the mean color.

getMeanColor

public static LabColor getMeanColor(int start,
                                    int end,
                                    RColor... colors)

Calculates the mean color of the input colors. With start and end a subset is defined. Just this subset will be used to calculate the mean.

Parameters:

start - Start index of the subset of the input colors (start < end). start will be member of the subset.

end - End index of the subset of the input colors (start < end). end will not be member of the subset.

colors - Colors (1 or more).

Returns:

The new LabColor object that represents the mean color.

getMeanColor

public static LabColor getMeanColor(int start,
                                    int end,
                                    java.util.ArrayList<RColor> colors)

Calculates the mean color of the input colors. With start and end a subset is defined. Just this subset will be used to calculate the mean.

Parameters:

start - Start index of the subset of the input colors (start < end). start will be member of the subset.

end - End index of the subset of the input colors (start < end). end will not be member of the subset.

colors - Colors.

Returns:

The new LabColor object that represents the mean color.

getLoss

public static java.lang.Float getLoss(RColor rvMean,
                                      RColor[] colors,
                                      ColorDifferenceMeasure m)

Calculates the loss - the mean distance of all members of colors to rvMean.

Parameters:

rvMean - A base color which will be used to calculate the distance to.

colors - Colors.

m - The measure which defines how the loss is calculated and which color model will be used. This should be an Lab color difference measure.

Returns:

The mean loss value.

getLoss

public static java.lang.Float getLoss(RColor rvMean,
                                      RColor[] colors,
                                      ColorDifferenceMeasure m,
                                      int start,
                                      int end)

Calculates the loss - the mean distance of all members of colors to rvMean. With start and end a subset is defined. Just this subset will be used to calculate the loss. start and end should be in the array range; otherwise this will produce an ArrayIndexOutOfBounds Exception.

Parameters:

rvMean - A base color which will be used to calculate the distance to.

colors - Colors.

m - The measure which defines how the loss is calculated and which color model will be used. This should be an Lab color difference measure.

start - Start index of the subset of the input colors (start < end). start will be member of the subset.

end - End index of the subset of the input colors (start < end). end will not be member of the subset.

Returns:

The mean loss value.

getLoss

public static java.lang.Float getLoss(RColor rvMean,
                                      java.util.ArrayList<RColor> lColors,
                                      ColorDifferenceMeasure m)

Calculates the loss - the mean distance of all members of colors to rvMean.

Parameters:

rvMean - A base color which will be used to calculate the distance to.

lColors - Colors.

m - The measure which defines how the loss is calculated and which color model will be used. This should be an Lab color difference measure.

Returns:

The mean loss value.

getLoss

public static java.lang.Float getLoss(RColor rvMean,
                                      java.util.ArrayList<RColor> lColors,
                                      ColorDifferenceMeasure m,
                                      int start,
                                      int end)

Calculates the loss - the mean distance of all members of colors to rvMean. With start and end a subset is defined. Just this subset will be used to calculate the loss. start and end should be in the array range; otherwise this will produce an ArrayIndexOutOfBounds Exception.

Parameters:

rvMean - A base color which will be used to calculate the distance to.

lColors - Colors.

m - The measure which defines how the loss is calculated and which color model will be used. This should be an Lab color difference measure.

start - Start index of the subset of the input colors (start < end). start will be member of the subset.

end - End index of the subset of the input colors (start < end). end will not be member of the subset.

Returns:

The mean loss value.

lerpColors

public static LabColor lerpColors(RColor input1,
                                  RColor input2,
                                  float amt)

Lerps the two input colors and creates a new color. The values of the colors will be interpolated linear. The interpolation is defined by the amt parameter. For amt=0 the outcome will be input1, for amt=1 the outcome will be input2.

Parameters:

input1 - The first color.

input2 - The second color.

amt - The lerping value [0, 1].

Returns:

A new 'mixed' color.

getRandomLab

public static LabColor getRandomLab()

Creates a new opaque LabColor with random values.

Returns:

The new color.

getChroma

public static float getChroma(java.lang.Float a,
                              java.lang.Float b)

Calculates the chroma value of a given set of a and b values.

Parameters:

a - The a value (e.g. getA() of any Lab color)

b - The b value (e.g. getB() of any Lab color)

Returns:

The chroma value (chroma of LCH color model)

getHue

public static float getHue(double a,
                           double b)

Calculates the hue value of a given set of a and b values.

Parameters:

a - The a value (e.g. getA() of any Lab color)

b - The b value (e.g. getB() of any Lab color)

Returns:

The hue value (hue of LCH color model)

toRGB

public RGBColor toRGB()

Description copied from interface: RColor

Returns a RGBColor representation of the current color. If the color is already a RGBColor, the original object will be return otherwise a new object will be created with converted color values. The resulting color referes to sRGB.

Specified by:

toRGB in interface RColor

Returns:

The RGBColor of the object.

toHSB

public HSBColor toHSB()

Description copied from interface: RColor

Returns a HSBColor representation of the current color. If the color is already a HSBColor, the original object will be return otherwise a new object will be created with converted color values.

Specified by:

toHSB in interface RColor

Returns:

The HSBColor of the object.

toXYZ

public XYZColor toXYZ()

Description copied from interface: RColor

Returns a XYZColor representation of the current color. If the color is already a XYZColor, the original object will be return otherwise a new object will be created with converted color values. The XYZColor refers to a D65/2° standard illuminant.

Specified by:

toXYZ in interface RColor

Returns:

The XYZColor of the object.

toLab

public LabColor toLab()

Description copied from interface: RColor

Returns a LabColor representation of the current color. If the color is already a LabColor, the original object will be return otherwise a new object will be created with converted color values. The conversion is done using the XYZColor.REFERENCE_X,Y and Z values as specific illuminants and observers.

Specified by:

toLab in interface RColor

Returns:

The LabColor of the object.

toLCH

public LCHColor toLCH()

Description copied from interface: RColor

Returns a LCHColor representation of the current color. If the color is already a LCHColor, the original object will be return otherwise a new object will be created with converted color values.

Specified by:

toLCH in interface RColor

Returns:

The LCHColor of the object.