---
title: "Rgb"
description: "An RGB color space is an additive color space using the [RGB][ColorModel.Rgb] color model (a
color is therefore represented by a tuple of 3 numbers).
A specific RGB color space is defined by the following properties:
* Three chromaticities of the red, green and blue primaries, which define the gamut of the color space.
* A white point chromaticity that defines the stimulus to which color space values are normalized (also just called \"white\").
* An opto-electronic transfer function, also called opto-electronic conversion function or often, and approximately, gamma function.
* An electro-optical transfer function, also called electo-optical conversion function or often, and approximately, gamma function.
* A range of valid RGB values (most commonly `[0..1]`).
The most commonly used RGB color space is [sRGB][ColorSpaces.Srgb].
### Primaries and white point chromaticities
In this implementation, the chromaticity of the primaries and the white point of an RGB color
space is defined in the CIE xyY color space. This color space separates the chromaticity of a
color, the x and y components, and its luminance, the Y component. Since the primaries and the
white point have full brightness, the Y component is assumed to be 1 and only the x and y
components are needed to encode them.
For convenience, this implementation also allows to define the primaries and white point in the
CIE XYZ space. The tristimulus XYZ values are internally converted to xyY.
[sRGB primaries and white
point](https://developer.android.com/reference/android/images/graphics/colorspace_srgb.png)
### Transfer functions
A transfer function is a color component conversion function, defined as a single variable,
monotonic mathematical function. It is applied to each individual component of a color. They are
used to perform the mapping between linear tristimulus values and non-linear electronic signal
value.
The *opto-electronic transfer function* (OETF or OECF) encodes tristimulus values in a scene to a
non-linear electronic signal value. An OETF is often expressed as a power function with an
exponent between 0.38 and 0.55 (the reciprocal of 1.8 to 2.6).
The *electro-optical transfer function* (EOTF or EOCF) decodes a non-linear electronic signal
value to a tristimulus value at the display. An EOTF is often expressed as a power function with
an exponent between 1.8 and 2.6.
Transfer functions are used as a compression scheme. For instance, linear sRGB values would
normally require 11 to 12 bits of precision to store all values that can be perceived by the
human eye. When encoding sRGB values using the appropriate OETF (see [sRGB][ColorSpaces.Srgb] for
an exact mathematical description of that OETF), the values can be compressed to only 8 bits
precision.
When manipulating RGB values, particularly sRGB values, it is safe to assume that these values
have been encoded with the appropriate OETF (unless noted otherwise). Encoded values are often
said to be in \"gamma space\". They are therefore defined in a non-linear space. This in turns
means that any linear operation applied to these values is going to yield mathematically
incorrect results (any linear interpolation such as gradient generation for instance, most image
processing functions such as blurs, etc.).
To properly process encoded RGB values you must first apply the EOTF to decode the value into
linear space. After processing, the RGB value must be encoded back to non-linear (\"gamma\") space.
Here is a formal description of the process, where `f` is the processing function to apply:
[See RGB equation](https://developer.android.com/reference/android/graphics/ColorSpace.Rgb)
If the transfer functions of the color space can be expressed as an ICC parametric curve as
defined in ICC.1:2004-10, the numeric parameters can be retrieved from [transferParameters]. This
can be useful to match color spaces for instance.
Some RGB color spaces, such as [ColorSpaces.Aces] and [scRGB][ColorSpaces.LinearExtendedSrgb],
are said to be linear because their transfer functions are the identity function: `f(x) = x`. If
the source and/or destination are known to be linear, it is not necessary to invoke the transfer
functions.
### Range
Most RGB color spaces allow RGB values in the range `[0..1]`. There are however a few RGB color
spaces that allow much larger ranges. For instance, [scRGB][ColorSpaces.ExtendedSrgb] is used to
manipulate the range `[-0.5..7.5]` while [ACES][ColorSpaces.Aces] can be used throughout the
range `[-65504, 65504]`.
[Extended sRGB and its large
range](https://developer.android.com/reference/android/images/graphics/colorspace_scrgb.png)
### Converting between RGB color spaces
Conversion between two color spaces is achieved by using an intermediate color space called the
profile connection space (PCS). The PCS used by this implementation is CIE XYZ. The conversion
operation is defined as such:
[See RGB equation](https://developer.android.com/reference/android/graphics/ColorSpace.Rgb)
Where `Tsrc` is the [RGB to XYZ transform][getTransform] of the source color space and `Tdst^-1`
the [XYZ to RGB transform][getInverseTransform] of the destination color space.
Many RGB color spaces commonly used with electronic devices use the standard illuminant
[D65][Illuminant.D65]. Care must be take however when converting between two RGB color spaces if
their white points do not match. This can be achieved by either calling [adapt] to adapt one or
both color spaces to a single common white point. This can be achieved automatically by calling
[ColorSpace.connect], which also handles non-RGB color spaces.
To learn more about the white point adaptation process, refer to the documentation of
[Adaptation]."
type: "class"
---
Class
Common
```kotlin
class Rgb
/**
* Creates a new RGB color space using a specified set of primaries and a specified white point.
*
* The primaries and white point can be specified in the CIE xyY space or in CIE XYZ. The length of
* the arrays depends on the chosen space:
* ```
* | Spaces | Primaries length | White point length |
* |--------|------------------|--------------------|
* | xyY | 6 | 2 |
* | XYZ | 9 | 3 |
* ```
*
* When the primaries and/or white point are specified in xyY, the Y component does not need to be
* specified and is assumed to be 1.0. Only the xy components are required.
*
* @param name Name of the color space, cannot be null, its length must be >= 1
* @param primaries RGB primaries as an array of 6 (xy) or 9 (XYZ) floats
* @param whitePoint Reference white as a [WhitePoint]
* @param transform Computed transform matrix that converts from RGB to XYZ, or `null` to compute it
* from `primaries` and `whitePoint`.
* @param oetf Opto-electronic transfer function, cannot be null
* @param eotf Electro-optical transfer function, cannot be null
* @param min The minimum valid value in this color space's RGB range
* @param max The maximum valid value in this color space's RGB range
* @param transferParameters Parameters for the transfer functions
* @param id ID of this color space as an integer between [ColorSpace.MinId] and [ColorSpace.MaxId]
* @throws IllegalArgumentException If any of the following conditions is met:
* * The name is null or has a length of 0.
* * The primaries array is null or has a length that is neither 6 or 9.
* * The white point array is null or has a length that is neither 2 or 3.
* * The OETF is null or the EOTF is null.
* * The minimum valid value is >= the maximum valid value.
* * The ID is not between [ColorSpace.MinId] and [ColorSpace.MaxId].
*/
internal constructor(
name: String,
primaries: FloatArray,
val whitePoint: WhitePoint,
transform: FloatArray?,
oetf: DoubleFunction,
eotf: DoubleFunction,
private val min: Float,
private val max: Float,
/**
* Returns the parameters used by the [electro-optical][eotf] and [opto-electronic][oetf]
* transfer functions. If the transfer functions do not match the ICC parametric curves defined
* in ICC.1:2004-10 (section 10.15), this method returns null.
*
* See [TransferParameters] for a full description of the transfer functions.
*
* @return An instance of [TransferParameters] or null if this color space's transfer functions
* do not match the equation defined in [TransferParameters]
*/
val transferParameters: TransferParameters?,
id: Int,
) : ColorSpace(name, ColorModel.Rgb, id)
```
An RGB color space is an additive color space using the `RGB` color model (a
color is therefore represented by a tuple of 3 numbers).
A specific RGB color space is defined by the following properties:
* Three chromaticities of the red, green and blue primaries, which define the gamut of the color space.
* A white point chromaticity that defines the stimulus to which color space values are normalized (also just called "white").
* An opto-electronic transfer function, also called opto-electronic conversion function or often, and approximately, gamma function.
* An electro-optical transfer function, also called electo-optical conversion function or often, and approximately, gamma function.
* A range of valid RGB values (most commonly ``0..1``).
The most commonly used RGB color space is `sRGB`.
### Primaries and white point chromaticities
In this implementation, the chromaticity of the primaries and the white point of an RGB color
space is defined in the CIE xyY color space. This color space separates the chromaticity of a
color, the x and y components, and its luminance, the Y component. Since the primaries and the
white point have full brightness, the Y component is assumed to be 1 and only the x and y
components are needed to encode them.
For convenience, this implementation also allows to define the primaries and white point in the
CIE XYZ space. The tristimulus XYZ values are internally converted to xyY.
`sRGB primaries and white
point`(https://developer.android.com/reference/android/images/graphics/colorspace_srgb.png)
### Transfer functions
A transfer function is a color component conversion function, defined as a single variable,
monotonic mathematical function. It is applied to each individual component of a color. They are
used to perform the mapping between linear tristimulus values and non-linear electronic signal
value.
The *opto-electronic transfer function* (OETF or OECF) encodes tristimulus values in a scene to a
non-linear electronic signal value. An OETF is often expressed as a power function with an
exponent between 0.38 and 0.55 (the reciprocal of 1.8 to 2.6).
The *electro-optical transfer function* (EOTF or EOCF) decodes a non-linear electronic signal
value to a tristimulus value at the display. An EOTF is often expressed as a power function with
an exponent between 1.8 and 2.6.
Transfer functions are used as a compression scheme. For instance, linear sRGB values would
normally require 11 to 12 bits of precision to store all values that can be perceived by the
human eye. When encoding sRGB values using the appropriate OETF (see `sRGB` for
an exact mathematical description of that OETF), the values can be compressed to only 8 bits
precision.
When manipulating RGB values, particularly sRGB values, it is safe to assume that these values
have been encoded with the appropriate OETF (unless noted otherwise). Encoded values are often
said to be in "gamma space". They are therefore defined in a non-linear space. This in turns
means that any linear operation applied to these values is going to yield mathematically
incorrect results (any linear interpolation such as gradient generation for instance, most image
processing functions such as blurs, etc.).
To properly process encoded RGB values you must first apply the EOTF to decode the value into
linear space. After processing, the RGB value must be encoded back to non-linear ("gamma") space.
Here is a formal description of the process, where `f` is the processing function to apply:
`See RGB equation`(https://developer.android.com/reference/android/graphics/ColorSpace.Rgb)
If the transfer functions of the color space can be expressed as an ICC parametric curve as
defined in ICC.1:2004-10, the numeric parameters can be retrieved from `transferParameters`. This
can be useful to match color spaces for instance.
Some RGB color spaces, such as `ColorSpaces.Aces` and `scRGB`,
are said to be linear because their transfer functions are the identity function: `f(x) = x`. If
the source and/or destination are known to be linear, it is not necessary to invoke the transfer
functions.
### Range
Most RGB color spaces allow RGB values in the range ``0..1``. There are however a few RGB color
spaces that allow much larger ranges. For instance, `scRGB` is used to
manipulate the range ``-0.5..7.5`` while `ACES` can be used throughout the
range ``-65504, 65504``.
`Extended sRGB and its large
range`(https://developer.android.com/reference/android/images/graphics/colorspace_scrgb.png)
### Converting between RGB color spaces
Conversion between two color spaces is achieved by using an intermediate color space called the
profile connection space (PCS). The PCS used by this implementation is CIE XYZ. The conversion
operation is defined as such:
`See RGB equation`(https://developer.android.com/reference/android/graphics/ColorSpace.Rgb)
Where `Tsrc` is the `RGB to XYZ transform` of the source color space and `Tdst^-1`
the `XYZ to RGB transform` of the destination color space.
Many RGB color spaces commonly used with electronic devices use the standard illuminant
`D65`. Care must be take however when converting between two RGB color spaces if
their white points do not match. This can be achieved by either calling `adapt` to adapt one or
both color spaces to a single common white point. This can be achieved automatically by calling
`ColorSpace.connect`, which also handles non-RGB color spaces.
To learn more about the white point adaptation process, refer to the documentation of
`Adaptation`.
## Secondary Constructors
```kotlin
constructor(
@Size(min = 1) name: String,
@Size(9) toXYZ: FloatArray,
oetf: (Double) -> Double,
eotf: (Double) -> Double,
) : this(
name,
computePrimaries(toXYZ),
computeWhitePoint(toXYZ),
null,
DoubleFunction { x -> oetf(x) },
DoubleFunction { x -> eotf(x) },
0.0f,
1.0f,
null,
MinId,
)
```
Creates a new RGB color space using a 3x3 column-major transform matrix. The transform matrix
must convert from the RGB space to the profile connection space CIE XYZ.
The range of the color space is imposed to be ``0..1``.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| toXYZ | 3x3 column-major transform matrix from RGB to the profile connection space CIE XYZ as an array of 9 floats, cannot be null |
| oetf | Opto-electronic transfer function, cannot be null |
| eotf | Electro-optical transfer function, cannot be null |
```kotlin
constructor(
@Size(min = 1) name: String,
@Size(min = 6, max = 9) primaries: FloatArray,
whitePoint: WhitePoint,
oetf: (Double) -> Double,
eotf: (Double) -> Double,
min: Float,
max: Float,
) : this(
name,
primaries,
whitePoint,
null,
DoubleFunction { x -> oetf(x) },
DoubleFunction { x -> eotf(x) },
min,
max,
null,
MinId,
)
```
Creates a new RGB color space using a specified set of primaries and a specified white point.
The primaries and white point can be specified in the CIE xyY space or in CIE XYZ. The length
of the arrays depends on the chosen space:
```
| Spaces | Primaries length | White point length |
|--------|------------------|--------------------|
| xyY | 6 | 2 |
| XYZ | 9 | 3 |
```
When the primaries and/or white point are specified in xyY, the Y component does not need to
be specified and is assumed to be 1.0. Only the xy components are required.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| primaries | RGB primaries as an array of 6 (xy) or 9 (XYZ) floats |
| whitePoint | Reference white as an array of 2 (xy) or 3 (XYZ) floats |
| oetf | Opto-electronic transfer function, cannot be null |
| eotf | Electro-optical transfer function, cannot be null |
| min | The minimum valid value in this color space's RGB range |
| max | The maximum valid value in this color space's RGB range |
```kotlin
constructor(
@Size(min = 1) name: String,
@Size(9) toXYZ: FloatArray,
function: TransferParameters,
) : this(name, computePrimaries(toXYZ), computeWhitePoint(toXYZ), function, MinId)
```
Creates a new RGB color space using a 3x3 column-major transform matrix. The transform matrix
must convert from the RGB space to the profile connection space CIE XYZ.
The range of the color space is imposed to be ``0..1``.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| toXYZ | 3x3 column-major transform matrix from RGB to the profile connection space CIE XYZ as an array of 9 floats, cannot be null |
| function | Parameters for the transfer functions |
```kotlin
constructor(
@Size(min = 1) name: String,
@Size(min = 6, max = 9) primaries: FloatArray,
whitePoint: WhitePoint,
function: TransferParameters,
) : this(name, primaries, whitePoint, function, MinId)
```
Creates a new RGB color space using a specified set of primaries and a specified white point.
The primaries and white point can be specified in the CIE xyY space or in CIE XYZ. The length
of the arrays depends on the chosen space:
```
| Spaces | Primaries length | White point length |
|--------|------------------|--------------------|
| xyY | 6 | 2 |
| XYZ | 9 | 3 |
```
When the primaries and/or white point are specified in xyY, the Y component does not need to
be specified and is assumed to be 1.0. Only the xy components are required.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| primaries | RGB primaries as an array of 6 (xy) or 9 (XYZ) floats |
| whitePoint | Reference white as an array of 2 (xy) or 3 (XYZ) floats |
| function | Parameters for the transfer functions |
```kotlin
internal constructor(
name: String,
primaries: FloatArray,
whitePoint: WhitePoint,
function: TransferParameters,
id: Int,
) : this(
name,
primaries,
whitePoint,
null,
generateOetf(function),
generateEotf(function),
0.0f,
1.0f,
function,
id,
)
```
Creates a new RGB color space using a specified set of primaries and a specified white point.
The primaries and white point can be specified in the CIE xyY space or in CIE XYZ. The length
of the arrays depends on the chosen space:
```
| Spaces | Primaries length | White point length |
|--------|------------------|--------------------|
| xyY | 6 | 2 |
| XYZ | 9 | 3 |
```
When the primaries and/or white point are specified in xyY, the Y component does not need to
be specified and is assumed to be 1.0. Only the xy components are required.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| primaries | RGB primaries as an array of 6 (xy) or 9 (XYZ) floats |
| whitePoint | Reference white as an array of 2 (xy) or 3 (XYZ) floats |
| function | Parameters for the transfer functions |
| id | ID of this color space as an integer between `ColorSpace.MinId` and `ColorSpace.MaxId` |
```kotlin
constructor(
@Size(min = 1) name: String,
@Size(9) toXYZ: FloatArray,
gamma: Double,
) : this(name, computePrimaries(toXYZ), computeWhitePoint(toXYZ), gamma, 0.0f, 1.0f, MinId)
```
Creates a new RGB color space using a 3x3 column-major transform matrix. The transform matrix
must convert from the RGB space to the profile connection space CIE XYZ.
The range of the color space is imposed to be ``0..1``.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| toXYZ | 3x3 column-major transform matrix from RGB to the profile connection space CIE XYZ as an array of 9 floats, cannot be null |
| gamma | Gamma to use as the transfer function |
```kotlin
constructor(
@Size(min = 1) name: String,
@Size(min = 6, max = 9) primaries: FloatArray,
whitePoint: WhitePoint,
gamma: Double,
) : this(name, primaries, whitePoint, gamma, 0.0f, 1.0f, MinId)
```
Creates a new RGB color space using a specified set of primaries and a specified white point.
The primaries and white point can be specified in the CIE xyY space or in CIE XYZ. The length
of the arrays depends on the chosen space:
```
| Spaces | Primaries length | White point length |
|--------|------------------|--------------------|
| xyY | 6 | 2 |
| XYZ | 9 | 3 |
```
When the primaries and/or white point are specified in xyY, the Y component does not need to
be specified and is assumed to be 1.0. Only the xy components are required.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| primaries | RGB primaries as an array of 6 (xy) or 9 (XYZ) floats |
| whitePoint | Reference white as an array of 2 (xy) or 3 (XYZ) floats |
| gamma | Gamma to use as the transfer function |
```kotlin
internal constructor(
name: String,
primaries: FloatArray,
whitePoint: WhitePoint,
gamma: Double,
min: Float,
max: Float,
id: Int,
) : this(
name,
primaries,
whitePoint,
null,
if (gamma == 1.0) DoubleIdentity
else DoubleFunction { x -> (if (x < 0.0) 0.0 else x).pow(1.0 / gamma) },
if (gamma == 1.0) DoubleIdentity
else DoubleFunction { x -> (if (x < 0.0) 0.0 else x).pow(gamma) },
min,
max,
TransferParameters(gamma, 1.0, 0.0, 0.0, 0.0),
id,
)
```
Creates a new RGB color space using a specified set of primaries and a specified white point.
The primaries and white point can be specified in the CIE xyY space or in CIE XYZ. The length
of the arrays depends on the chosen space:
```
| Spaces | Primaries length | White point length |
|--------|------------------|--------------------|
| xyY | 6 | 2 |
| XYZ | 9 | 3 |
```
When the primaries and/or white point are specified in xyY, the Y component does not need to
be specified and is assumed to be 1.0. Only the xy components are required.
#### Parameters
| | |
| --- | --- |
| name | Name of the color space, cannot be null, its length must be >= 1 |
| primaries | RGB primaries as an array of 6 (xy) or 9 (XYZ) floats |
| whitePoint | Reference white as an array of 2 (xy) or 3 (XYZ) floats |
| gamma | Gamma to use as the transfer function |
| min | The minimum valid value in this color space's RGB range |
| max | The maximum valid value in this color space's RGB range |
| id | ID of this color space as an integer between `ColorSpace.MinId` and `ColorSpace.MaxId` |
```kotlin
internal constructor(
colorSpace: Rgb,
transform: FloatArray,
whitePoint: WhitePoint,
) : this(
colorSpace.name,
colorSpace.primaries,
whitePoint,
transform,
colorSpace.oetfOrig,
colorSpace.eotfOrig,
colorSpace.min,
colorSpace.max,
colorSpace.transferParameters,
MinId,
)
```
Creates a copy of the specified color space with a new transform.
#### Parameters
| | |
| --- | --- |
| colorSpace | The color space to create a copy of |
## Properties
Common
```kotlin
val oetf: (Double) -> Double
```
Returns the opto-electronic transfer function (OETF) of this color space. The inverse
function is the electro-optical transfer function (EOTF) returned by `eotf`. These functions
are defined to satisfy the following equality for x ∈ ``0..1``:
OETF(EOTF(x) = EOTF(OETF(x)) = x
For RGB colors, this function can be used to convert from linear space to "gamma space"
(gamma encoded). The terms gamma space and gamma encoded are frequently used because many
OETFs can be closely approximated using a simple power function of the form x^γ (the
approximation of the `sRGB` OETF uses γ = 2.2 for instance).
#### Returns
| | |
| --- | --- |
| | A transfer function that converts from linear space to "gamma space" |
Common
```kotlin
val eotf: (Double) -> Double
```
Returns the electro-optical transfer function (EOTF) of this color space. The inverse
function is the opto-electronic transfer function (OETF) returned by `oetf`. These functions
are defined to satisfy the following equality for x in ``0..1``:
OETF(EOTF(x) = EOTF(OETF(x)) = x
For RGB colors, this function can be used to convert from "gamma space" (gamma encoded) to
linear space. The terms gamma space and gamma encoded are frequently used because many EOTFs
can be closely approximated using a simple power function of the form x^γ (the approximation
of the `sRGB` EOTF uses γ = 2.2 for instance).
#### Returns
| | |
| --- | --- |
| | A transfer function that converts from "gamma space" to linear space |
## Functions
```kotlin
@Size(6) fun getPrimaries(): FloatArray
```
Returns the primaries of this color space as a new array of 6 floats. The Y component is
assumed to be 1 and is therefore not copied into the destination. The x and y components of
the first primary are written in the array at positions 0 and 1 respectively.
#### Returns
| | |
| --- | --- |
| | A new non-null array of 2 floats |
```kotlin
@Size(9) fun getTransform(): FloatArray
```
Returns the transform of this color space as a new array. The transform is used to convert
from RGB to XYZ (with the same white point as this color space). To connect color spaces, you
must first `adapt` them to the same white point.
It is recommended to use `ColorSpace.connect` to convert between color spaces.
#### Returns
| | |
| --- | --- |
| | A new array of 9 floats |
```kotlin
@Size(9) fun getInverseTransform(): FloatArray
```
Returns the inverse transform of this color space as a new array. The inverse transform is
used to convert from XYZ to RGB (with the same white point as this color space). To connect
color spaces, you must first `adapt` them to the same white point.
It is recommended to use `ColorSpace.connect` to convert between color spaces.
#### Returns
| | |
| --- | --- |
| | A new array of 9 floats |
```kotlin
@Size(min = 6)
fun getPrimaries(@Size(min = 6) primaries: FloatArray): FloatArray
```
Copies the primaries of this color space in specified array. The Y component is assumed to be
1 and is therefore not copied into the destination. The x and y components of the first
primary are written in the array at positions 0 and 1 respectively.
#### Parameters
| | |
| --- | --- |
| primaries | The destination array, cannot be null, its length must be >= 6 |
#### Returns
| | |
| --- | --- |
| | `primaries` array, modified to contain the primaries of this color space. |
```kotlin
@Size(min = 9)
fun getTransform(@Size(min = 9) transform: FloatArray): FloatArray
```
Copies the transform of this color space in specified array. The transform is used to convert
from RGB to XYZ (with the same white point as this color space). To connect color spaces, you
must first `adapt` them to the same white point.
It is recommended to use `ColorSpace.connect` to convert between color spaces.
#### Parameters
| | |
| --- | --- |
| transform | The destination array, cannot be null, its length must be >= 9 |
#### Returns
| | |
| --- | --- |
| | `transform`, modified to contain the transform for this color space. |
```kotlin
@Size(min = 9)
fun getInverseTransform(@Size(min = 9) inverseTransform: FloatArray): FloatArray
```
Copies the inverse transform of this color space in specified array. The inverse transform is
used to convert from XYZ to RGB (with the same white point as this color space). To connect
color spaces, you must first `adapt` them to the same white point.
It is recommended to use `ColorSpace.connect` to convert between color spaces.
#### Parameters
| | |
| --- | --- |
| inverseTransform | The destination array, cannot be null, its length must be >= 9 |
#### Returns
| | |
| --- | --- |
| | The `inverseTransform` array passed as a parameter, modified to contain the inverse transform of this color space. |
```kotlin
@Size(3)
fun toLinear(r: Float, g: Float, b: Float): FloatArray
```
Decodes an RGB value to linear space. This is achieved by applying this color space's
electro-optical transfer function to the supplied values.
Refer to the documentation of `Rgb` for more information about transfer functions and their
use for encoding and decoding RGB values.
#### Parameters
| | |
| --- | --- |
| r | The red component to decode to linear space |
| g | The green component to decode to linear space |
| b | The blue component to decode to linear space |
#### Returns
| | |
| --- | --- |
| | A new array of 3 floats containing linear RGB values |
```kotlin
@Size(min = 3)
fun toLinear(@Size(min = 3) v: FloatArray): FloatArray
```
Decodes an RGB value to linear space. This is achieved by applying this color space's
electro-optical transfer function to the first 3 values of the supplied array. The result is
stored back in the input array.
Refer to the documentation of `Rgb` for more information about transfer functions and their
use for encoding and decoding RGB values.
#### Parameters
| | |
| --- | --- |
| v | A non-null array of non-linear RGB values, its length must be at least 3 |
#### Returns
| | |
| --- | --- |
| | `v`, containing linear RGB values |
```kotlin
@Size(3)
fun fromLinear(r: Float, g: Float, b: Float): FloatArray
```
Encodes an RGB value from linear space to this color space's "gamma space". This is achieved
by applying this color space's opto-electronic transfer function to the supplied values.
Refer to the documentation of `Rgb` for more information about transfer functions and their
use for encoding and decoding RGB values.
#### Parameters
| | |
| --- | --- |
| r | The red component to encode from linear space |
| g | The green component to encode from linear space |
| b | The blue component to encode from linear space |
#### Returns
| | |
| --- | --- |
| | A new array of 3 floats containing non-linear RGB values |
```kotlin
@Size(min = 3)
fun fromLinear(@Size(min = 3) v: FloatArray): FloatArray
```
Encodes an RGB value from linear space to this color space's "gamma space". This is achieved
by applying this color space's opto-electronic transfer function to the first 3 values of the
supplied array. The result is stored back in the input array.
Refer to the documentation of `Rgb` for more information about transfer functions and their
use for encoding and decoding RGB values.
#### Parameters
| | |
| --- | --- |
| v | A non-null array of linear RGB values, its length must be at least 3 |
#### Returns
| | |
| --- | --- |
| | `v`, containing non-linear RGB values |
## Companion Object