Module cam16

Types for the CIE CAM16 color appearance model.

CIE CAM16 is a color appearance model that tries to predict the appearance of a color under certain viewing conditions, as specified via the Parameters type. The Cam16 type has descriptions for the CAM16 attributes. The Color appearance model page on Wikipedia has some history and background as well.

Converting Between XYZ and CAM16

The CIE CAM16 implementation in Palette has the Cam16 type and its partial variants on one side of the boundary, and Xyz on the other. Going between Xyz and Cam16 requires the viewing conditions to be specified as Parameters.

use palette::{
    Srgb, FromColor, IntoColor,
    cam16::{Cam16, Parameters},
};

// Customize these according to the viewing conditions:
let mut example_parameters = Parameters::default_static_wp(40.0);

// CAM16 from sRGB, or most other color spaces:
let rgb = Srgb::new(0.3f32, 0.8, 0.1);
let cam16_from_rgb = Cam16::from_xyz(rgb.into_color(), example_parameters);

// sRGB from CAM16, using lightness, chroma and hue by default:
let rgb_from_cam16 = Srgb::from_color(cam16_from_rgb.into_xyz(example_parameters));

For more control over the attributes to use when converting from CAM16, one of the partial CAM16 types can be used:

• Cam16Jch: lightness and chroma.
• Cam16Jmh: lightness and colorfulness.
• Cam16Jsh: lightness and saturation.
• Cam16Qch: brightness and chroma.
• Cam16Qmh: brightness and colorfulness.
• Cam16Qsh: brightness and saturation.

Generic traits and functions can make use of the IntoCam16Unclamped, FromCam16Unclamped, Cam16IntoUnclamped, and Cam16FromUnclamped traits. They are similar to the traits from the convert module and help abstracting away most of the implementation details.

The CAM16-UCS Color Space

CIE CAM16 specifies a visually uniform color space that can be used for color manipulation. It’s represented by the Cam16UcsJmh and Cam16UcsJab types, similar to Lch and Lab.

use palette::{
    Srgb, FromColor, IntoColor,
    cam16::{Cam16Jmh, Parameters, Cam16UcsJmh},
};

// Customize these according to the viewing conditions:
let mut example_parameters = Parameters::default_static_wp(40.0);

// CAM16-UCS from sRGB, or most other color spaces:
let rgb = Srgb::new(0.3f32, 0.8, 0.1);
let cam16 = Cam16Jmh::from_xyz(rgb.into_color(), example_parameters);
let mut ucs_from_rgb = Cam16UcsJmh::from_color(cam16);

// Shift the hue by 120 degrees in CAM16-UCS:
ucs_from_rgb.hue += 120.0;

// Convert back to sRGB under the same viewing conditions:
let rgb = Srgb::from_color(Cam16Jmh::from_color(ucs_from_rgb).into_xyz(example_parameters));

Modules

• cam16_jch
  Partial CIE CAM16, with lightness and chroma, and helper types.
• cam16_jmh
  Partial CIE CAM16, with lightness and colorfulness, and helper types.
• cam16_jsh
  Partial CIE CAM16, with lightness and saturation, and helper types.
• cam16_qch
  Partial CIE CAM16, with brightness and chroma, and helper types.
• cam16_qmh
  Partial CIE CAM16, with brightness and colorfulness, and helper types.
• cam16_qsh
  Partial CIE CAM16, with brightness and saturation, and helper types.

Structs

• BakedParameters
  Pre-calculated variables for CAM16, that only depend on the viewing conditions.
• Cam16
  The CIE CAM16 color appearance model.
• Cam16Jch
  Partial CIE CAM16, with lightness and chroma.
• Cam16Jmh
  Partial CIE CAM16, with lightness and colorfulness.
• Cam16Jsh
  Partial CIE CAM16, with lightness and saturation.
• Cam16Qch
  Partial CIE CAM16, with brightness and chroma.
• Cam16Qmh
  Partial CIE CAM16, with brightness and colorfulness.
• Cam16Qsh
  Partial CIE CAM16, with brightness and saturation.
• Cam16UcsJab
  The Cartesian form of CAM16-UCS, or J’ a’ b’.
• Cam16UcsJabIter
  An iterator for Cam16UcsJab values.
• Cam16UcsJmh
  The polar form of CAM16-UCS, or J’M’h’.
• Cam16UcsJmhIter
  An iterator for Cam16UcsJmh values.
• Parameters
  Parameters for CAM16 that describe the viewing conditions.
• StaticWp
  Represents a static white point in Parameters, as opposed to a dynamic Xyz value.

Enums

• Discounting
  The degree of discounting of (or adaptation to) the illuminant.
• Surround
  A description of the peripheral area.

Traits

• Cam16FromUnclamped
  A trait for converting into a CAM16 color type from C without clamping.
• Cam16IntoUnclamped
  A trait for converting from a CAM16 color type into C without clamping.
• FromCam16Unclamped
  A trait for converting from a CAM16 color type C without clamping.
• IntoCam16Unclamped
  A trait for converting into a CAM16 color type C without clamping.
• WhitePointParameter
  A trait for types that can be used as white point parameters in Parameters.

Type Aliases

• Cam16Jcha
  Partial CIE CAM16 with lightness, chroma, and an alpha component.
• Cam16Jmha
  Partial CIE CAM16 with lightness, colorfulness, and an alpha component.
• Cam16Jsha
  Partial CIE CAM16 with lightness, saturation, and an alpha component.
• Cam16Qcha
  Partial CIE CAM16 with brightness, chroma, and an alpha component.
• Cam16Qmha
  Partial CIE CAM16 with brightness, colorfulness, and an alpha component.
• Cam16Qsha
  Partial CIE CAM16 with brightness, saturation, and an alpha component.
• Cam16UcsJaba
  Cartesian CAM16-UCS with an alpha component.
• Cam16UcsJmha
  Polar CAM16-UCS with an alpha component.
• Cam16a
  CIE CAM16 with an alpha component.