# Class ColorSpace

java.lang.Object
java.awt.color.ColorSpace

All Implemented Interfaces:
  `Serializable`

Direct Known Subclasses:
  `ICC_ColorSpace`

public abstract class ColorSpace extends Object implements Serializable
This abstract class is used to serve as a color space tag to identify the specific color space of a `Color` object or, via a `ColorModel` object, of an `Image`, a `BufferedImage`, or a `GraphicsDevice`. It contains methods that transform colors in a specific color space to/from sRGB and to/from a well-defined CIEXYZ color space.

For purposes of the methods in this class, colors are represented as arrays of color components represented as floats in a normalized range defined by each `ColorSpace`. For many `ColorSpaces` (e.g. sRGB), this range is 0.0 to 1.0. However, some `ColorSpaces` have components whose values have a different range. Methods are provided to inquire per component minimum and maximum normalized values.

Several variables are defined for purposes of referring to color space types (e.g. `TYPE_RGB`, `TYPE_XYZ`, etc.) and to refer to specific color spaces (e.g. `CS_sRGB` and `CS_CIEXYZ`). sRGB is a proposed standard RGB color space. For more information, see http://www.w3.org/pub/WWW/Graphics/Color/sRGB.html.

The purpose of the methods to transform to/from the well-defined CIEXYZ color space is to support conversions between any two color spaces at a reasonably high degree of accuracy. It is expected that particular implementations of subclasses of `ColorSpace` (e.g. `ICC_ColorSpace`) will support high performance conversion based on underlying platform color management systems.

The `CS_CIEXYZ` space used by the `toCIEXYZ/fromCIEXYZ` methods can be described as follows:

         CIEXYZ
         viewing illuminance: 200 lux
         viewing white point: CIE D50
         media white point: "that of a perfectly reflecting diffuser" -- D50
         media black point: 0 lux or 0 Reflectance
         flare: 1 percent
         surround: 20percent of the media white point
         media description: reflection print (i.e., RLAB, Hunt viewing media)
         note: For developers creating an ICC profile for this conversion
               space, the following is applicable. Use a simple Von Kries
               white point adaptation folded into the 3X3 matrix parameters
               and fold the flare and surround effects into the three
               one-dimensional lookup tables (assuming one uses the minimal
               model for monitors).

See Also:
  - `ICC_ColorSpace`
  - Serialized Form

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final int`
  `CS_CIEXYZ`
  The built-in CIEXYZ conversion color space defined above.
  `static final int`
  `CS_GRAY`
  The built-in linear gray scale color space.
  `static final int`
  `CS_LINEAR_RGB`
  The built-in linear RGB color space.
  `static final int`
  `CS_PYCC`
  The built-in Photo YCC conversion color space.
  `static final int`
  `CS_sRGB`
  The built-in sRGB color space defined at http://www.w3.org/pub/WWW/Graphics/Color/sRGB.html.
  `static final int`
  `TYPE_2CLR`
  Generic 2 component color spaces.
  `static final int`
  `TYPE_3CLR`
  Generic 3 component color spaces.
  `static final int`
  `TYPE_4CLR`
  Generic 4 component color spaces.
  `static final int`
  `TYPE_5CLR`
  Generic 5 component color spaces.
  `static final int`
  `TYPE_6CLR`
  Generic 6 component color spaces.
  `static final int`
  `TYPE_7CLR`
  Generic 7 component color spaces.
  `static final int`
  `TYPE_8CLR`
  Generic 8 component color spaces.
  `static final int`
  `TYPE_9CLR`
  Generic 9 component color spaces.
  `static final int`
  `TYPE_ACLR`
  Generic 10 component color spaces.
  `static final int`
  `TYPE_BCLR`
  Generic 11 component color spaces.
  `static final int`
  `TYPE_CCLR`
  Generic 12 component color spaces.
  `static final int`
  `TYPE_CMY`
  Any of the family of CMY color spaces.
  `static final int`
  `TYPE_CMYK`
  Any of the family of CMYK color spaces.
  `static final int`
  `TYPE_DCLR`
  Generic 13 component color spaces.
  `static final int`
  `TYPE_ECLR`
  Generic 14 component color spaces.
  `static final int`
  `TYPE_FCLR`
  Generic 15 component color spaces.
  `static final int`
  `TYPE_GRAY`
  Any of the family of GRAY color spaces.
  `static final int`
  `TYPE_HLS`
  Any of the family of HLS color spaces.
  `static final int`
  `TYPE_HSV`
  Any of the family of HSV color spaces.
  `static final int`
  `TYPE_Lab`
  Any of the family of Lab color spaces.
  `static final int`
  `TYPE_Luv`
  Any of the family of Luv color spaces.
  `static final int`
  `TYPE_RGB`
  Any of the family of RGB color spaces.
  `static final int`
  `TYPE_XYZ`
  Any of the family of XYZ color spaces.
  `static final int`
  `TYPE_YCbCr`
  Any of the family of YCbCr color spaces.
  `static final int`
  `TYPE_Yxy`
  Any of the family of Yxy color spaces.

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `ColorSpace(int type, int numComponents)`
  Constructs a `ColorSpace` object given a color space type and the number of components.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `abstract float[]`
  `fromCIEXYZ(float[] colorvalue)`
  Transforms a color value assumed to be in the `CS_CIEXYZ` conversion color space into this `ColorSpace`.
  `abstract float[]`
  `fromRGB(float[] rgbvalue)`
  Transforms a color value assumed to be in the default `CS_sRGB` color space into this `ColorSpace`.
  `static ColorSpace`
  `getInstance(int cspace)`
  Returns a `ColorSpace` representing one of the specific predefined color spaces.
  `float`
  `getMaxValue(int component)`
  Returns the maximum normalized color component value for the specified component.
  `float`
  `getMinValue(int component)`
  Returns the minimum normalized color component value for the specified component.
  `String`
  `getName(int component)`
  Returns the name of the component given the component index.
  `int`
  `getNumComponents()`
  Returns the number of components of this ColorSpace.
  `int`
  `getType()`
  Returns the color space type of this `ColorSpace` (for example `TYPE_RGB`, `TYPE_XYZ`, ...).
  `boolean`
  `isCS_sRGB()`
  Returns true if the `ColorSpace` is `CS_sRGB`.
  `abstract float[]`
  `toCIEXYZ(float[] colorvalue)`
  Transforms a color value assumed to be in this `ColorSpace` into the `CS_CIEXYZ` conversion color space.
  `abstract float[]`
  `toRGB(float[] colorvalue)`
  Transforms a color value assumed to be in this `ColorSpace` into a value in the default `CS_sRGB` color space.

  ### Methods declared in class java.lang.Object

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

- ## Field Details

  - ### TYPE_XYZ

    @Native public static final int TYPE_XYZ
    Any of the family of XYZ color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_Lab

    @Native public static final int TYPE_Lab
    Any of the family of Lab color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_Luv

    @Native public static final int TYPE_Luv
    Any of the family of Luv color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_YCbCr

    @Native public static final int TYPE_YCbCr
    Any of the family of YCbCr color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_Yxy

    @Native public static final int TYPE_Yxy
    Any of the family of Yxy color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_RGB

    @Native public static final int TYPE_RGB
    Any of the family of RGB color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_GRAY

    @Native public static final int TYPE_GRAY
    Any of the family of GRAY color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_HSV

    @Native public static final int TYPE_HSV
    Any of the family of HSV color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_HLS

    @Native public static final int TYPE_HLS
    Any of the family of HLS color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_CMYK

    @Native public static final int TYPE_CMYK
    Any of the family of CMYK color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_CMY

    @Native public static final int TYPE_CMY
    Any of the family of CMY color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_2CLR

    @Native public static final int TYPE_2CLR
    Generic 2 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_3CLR

    @Native public static final int TYPE_3CLR
    Generic 3 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_4CLR

    @Native public static final int TYPE_4CLR
    Generic 4 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_5CLR

    @Native public static final int TYPE_5CLR
    Generic 5 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_6CLR

    @Native public static final int TYPE_6CLR
    Generic 6 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_7CLR

    @Native public static final int TYPE_7CLR
    Generic 7 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_8CLR

    @Native public static final int TYPE_8CLR
    Generic 8 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_9CLR

    @Native public static final int TYPE_9CLR
    Generic 9 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_ACLR

    @Native public static final int TYPE_ACLR
    Generic 10 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_BCLR

    @Native public static final int TYPE_BCLR
    Generic 11 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_CCLR

    @Native public static final int TYPE_CCLR
    Generic 12 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_DCLR

    @Native public static final int TYPE_DCLR
    Generic 13 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_ECLR

    @Native public static final int TYPE_ECLR
    Generic 14 component color spaces.
    See Also:
      - Constant Field Values

  - ### TYPE_FCLR

    @Native public static final int TYPE_FCLR
    Generic 15 component color spaces.
    See Also:
      - Constant Field Values

  - ### CS_sRGB

    @Native public static final int CS_sRGB
    The built-in sRGB color space defined at http://www.w3.org/pub/WWW/Graphics/Color/sRGB.html.
    See Also:
      - Constant Field Values

  - ### CS_LINEAR_RGB

    @Native public static final int CS_LINEAR_RGB
    The built-in linear RGB color space. This space is based on the same RGB primaries as `CS_sRGB`, but has a linear tone reproduction curve.
    See Also:
      - Constant Field Values

  - ### CS_CIEXYZ

    @Native public static final int CS_CIEXYZ
    The built-in CIEXYZ conversion color space defined above.
    See Also:
      - Constant Field Values

  - ### CS_PYCC

    @Native public static final int CS_PYCC
    The built-in Photo YCC conversion color space.
    See Also:
      - Constant Field Values

  - ### CS_GRAY

    @Native public static final int CS_GRAY
    The built-in linear gray scale color space.
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### ColorSpace

    protected ColorSpace(int type, int numComponents)
    Constructs a `ColorSpace` object given a color space type and the number of components.
    Parameters:
      `type` - one of the `ColorSpace` type constants
      `numComponents` - the number of components in the color space

- ## Method Details

  - ### getInstance

    public static ColorSpace getInstance(int cspace)
    Returns a `ColorSpace` representing one of the specific predefined color spaces.
    Parameters:
      `cspace` - a specific color space identified by one of the predefined class constants (e.g. `CS_sRGB`, `CS_LINEAR_RGB`, `CS_CIEXYZ`, `CS_GRAY`, or `CS_PYCC`)
    Returns:
      the requested `ColorSpace` object
    Throws:
      `IllegalArgumentException` - if `cspace` is not one of the predefined color space types

  - ### isCS_sRGB

    public boolean isCS_sRGB()
    Returns true if the `ColorSpace` is `CS_sRGB`.
    Returns:
      `true` if this is a `CS_sRGB` color space, `false` if it is not

  - ### toRGB

    public abstract float[] toRGB(float[] colorvalue)
    Transforms a color value assumed to be in this `ColorSpace` into a value in the default `CS_sRGB` color space.

    This method transforms color values using algorithms designed to produce the best perceptual match between input and output colors. In order to do colorimetric conversion of color values, you should use the `toCIEXYZ` method of this color space to first convert from the input color space to the CS_CIEXYZ color space, and then use the `fromCIEXYZ` method of the `CS_sRGB` color space to convert from `CS_CIEXYZ` to the output color space. See `toCIEXYZ` and `fromCIEXYZ` for further information.

    Parameters:
      `colorvalue` - a float array with length of at least the number of components in this `ColorSpace`
    Returns:
      a float array of length 3
    Throws:
      `ArrayIndexOutOfBoundsException` - if array length is not at least the number of components in this `ColorSpace`
      `NullPointerException` - if `colorvalue` is `null`

  - ### fromRGB

    public abstract float[] fromRGB(float[] rgbvalue)
    Transforms a color value assumed to be in the default `CS_sRGB` color space into this `ColorSpace`.

    This method transforms color values using algorithms designed to produce the best perceptual match between input and output colors. In order to do colorimetric conversion of color values, you should use the `toCIEXYZ` method of the `CS_sRGB` color space to first convert from the input color space to the `CS_CIEXYZ` color space, and then use the `fromCIEXYZ` method of this color space to convert from `CS_CIEXYZ` to the output color space. See `toCIEXYZ` and `fromCIEXYZ` for further information.

    Parameters:
      `rgbvalue` - a float array with length of at least 3
    Returns:
      a float array with length equal to the number of components in this `ColorSpace`
    Throws:
      `ArrayIndexOutOfBoundsException` - if array length is not at least 3
      `NullPointerException` - if `rgbvalue` is `null`

  - ### toCIEXYZ

    public abstract float[] toCIEXYZ(float[] colorvalue)
    Transforms a color value assumed to be in this `ColorSpace` into the `CS_CIEXYZ` conversion color space.

    This method transforms color values using relative colorimetry, as defined by the International Color Consortium standard. This means that the XYZ values returned by this method are represented relative to the D50 white point of the `CS_CIEXYZ` color space. This representation is useful in a two-step color conversion process in which colors are transformed from an input color space to `CS_CIEXYZ` and then to an output color space. This representation is not the same as the XYZ values that would be measured from the given color value by a colorimeter. A further transformation is necessary to compute the XYZ values that would be measured using current CIE recommended practices. See the `toCIEXYZ` method of `ICC_ColorSpace` for further information.

    Parameters:
      `colorvalue` - a float array with length of at least the number of components in this `ColorSpace`
    Returns:
      a float array of length 3
    Throws:
      `ArrayIndexOutOfBoundsException` - if array length is not at least the number of components in this `ColorSpace`
      `NullPointerException` - if `colorvalue` is `null`

  - ### fromCIEXYZ

    public abstract float[] fromCIEXYZ(float[] colorvalue)
    Transforms a color value assumed to be in the `CS_CIEXYZ` conversion color space into this `ColorSpace`.

    This method transforms color values using relative colorimetry, as defined by the International Color Consortium standard. This means that the XYZ argument values taken by this method are represented relative to the D50 white point of the `CS_CIEXYZ` color space. This representation is useful in a two-step color conversion process in which colors are transformed from an input color space to `CS_CIEXYZ` and then to an output color space. The color values returned by this method are not those that would produce the XYZ value passed to the method when measured by a colorimeter. If you have XYZ values corresponding to measurements made using current CIE recommended practices, they must be converted to D50 relative values before being passed to this method. See the `fromCIEXYZ` method of `ICC_ColorSpace` for further information.

    Parameters:
      `colorvalue` - a float array with length of at least 3
    Returns:
      a float array with length equal to the number of components in this `ColorSpace`
    Throws:
      `ArrayIndexOutOfBoundsException` - if array length is not at least 3
      `NullPointerException` - if `colorvalue` is `null`

  - ### getType

    public int getType()
    Returns the color space type of this `ColorSpace` (for example `TYPE_RGB`, `TYPE_XYZ`, ...). The type defines the number of components of the color space and the interpretation, e.g. `TYPE_RGB` identifies a color space with three components - red, green, and blue. It does not define the particular color characteristics of the space, e.g. the chromaticities of the primaries.
    Returns:
      the type constant that represents the type of this `ColorSpace`

  - ### getNumComponents

    public int getNumComponents()
    Returns the number of components of this ColorSpace.
    Returns:
      the number of components in this `ColorSpace`

  - ### getName

    public String getName(int component)
    Returns the name of the component given the component index.
    Parameters:
      `component` - the component index
    Returns:
      the name of the component at the specified index
    Throws:
      `IllegalArgumentException` - if `component` is less than 0 or greater than `numComponents - 1`

  - ### getMinValue

    public float getMinValue(int component)
    Returns the minimum normalized color component value for the specified component. The default implementation in this abstract class returns 0.0 for all components. Subclasses should override this method if necessary.
    Parameters:
      `component` - the component index
    Returns:
      the minimum normalized component value
    Throws:
      `IllegalArgumentException` - if component is less than 0 or greater than `numComponents - 1`
    Since:
      1.4

  - ### getMaxValue

    public float getMaxValue(int component)
    Returns the maximum normalized color component value for the specified component. The default implementation in this abstract class returns 1.0 for all components. Subclasses should override this method if necessary.
    Parameters:
      `component` - the component index
    Returns:
      the maximum normalized component value
    Throws:
      `IllegalArgumentException` - if component is less than 0 or greater than `numComponents - 1`
    Since:
      1.4