IPT
The IPT color space is not registered in Color by default
Properties
Name: ipt
White Point: D65 / 2˚
Coordinates:
| Name | Range* |
|---|---|
i | [0, 1] |
p | [-1, 1] |
t | [-1, 1] |
* Space is not bound to the range and is only used as a reference to define percentage inputs/outputs.
The sRGB gamut represented within the IPT color space.
Ebner and Fairchild addressed the issue of non-constant lines of hue in their color space dubbed IPT. The IPT color space converts D65-adapted XYZ data (XD65, YD65, ZD65) to long-medium-short cone response data (LMS) using an adapted form of the Hunt-Pointer-Estevez matrix (MHPE(D65)).
The IPT color appearance model excels at providing a formulation for hue where a constant hue value equals a constant perceived hue independent of the values of lightness and chroma (which is the general ideal for any color appearance model, but hard to achieve). It is therefore well-suited for gamut mapping implementations.
Channel Aliases
| Channels | Aliases |
|---|---|
i | intensity |
p | protan |
t | tritan |
Inputs
The IPT space is not currently supported in the CSS spec, the parsed input and string output formats use the color() function format using the custom name --ipt:
color(--ipt i p t / a) // Color function
The string representation of the color object and the default string output use the color(--ipt i p t / a) form.
>>> Color("ipt", [0.45616, 0.62086, 0.44282])
color(--ipt 0.45616 0.62086 0.44282 / 1)
>>> Color("ipt", [0.64877, 0.189, 0.5303]).to_string()
'color(--ipt 0.64877 0.189 0.5303)'
Registering
from coloraide import Color as Base
from coloraide.spaces.ipt import IPT
class Color(Base): ...
Color.register(IPT())