Uniform Color Spaces

Sometimes we care a lot about the distance between colors. For example, you might want to make sure that a color on your wall in a certain lighting environment will match the test swatch you were given, to within a specified tolerance. Or you want to make sure that two colors are distinguishable in a graph.

This is the job of a uniform color space. Its job is to match distances between points in space to how close they look to humans. They tend to be very algebraically messy, with many small adjustments for quirks of the visual system and no easy bounds, and don't preserve hue/chroma/lightness as much as spaces like Oklch. But they're excellent for color distances.

We'll use CAM16-UCS, a uniform color space designed in 2016. It's the current state of the art in color difference estimation. I've displayed the sRGB gamut in this space opposite. Note how blue gets more real estate than green or red: this makes hue estimation harder but accounts for our extra sensitivity to those colors. Also note how the space is pretty odd-shaped.

Uniform Color Spaces

Sometimes we care a lot about the distance between colors. For example, you might want to make sure that a color on your wall in a certain lighting environment will match the test swatch you were given, to within a specified tolerance. Or you want to make sure that two colors are distinguishable in a graph.

This is the job of a uniform color space. Its job is to match distances between points in space to how close they look to humans. They tend to be very algebraically messy, with many small adjustments for quirks of the visual system and no easy bounds, and don't preserve hue/chroma/lightness as much as spaces like Oklch. But they're excellent for color distances.

We'll use CAM16-UCS, a uniform color space designed in 2016. It's the current state of the art in color difference estimation. I've displayed the sRGB gamut in this space opposite. Note how blue gets more real estate than green or red: this makes hue estimation harder but accounts for our extra sensitivity to those colors. Also note how the space is pretty odd-shaped.