Migrating to v3

From v2

Every claim verified against the published v2.3.2 source.

1. Flat arguments; arrays mean batches

rgb.lab([50, 50, 50]);               // v2
rgb.lab(50, 50, 50);                 // v3 scalar → [l, a, b]
rgb.lab([50, 50, 50]);               // v3 batch of one → Float64Array [l, a, b]
rgb.lab([50, 50, 50, 20, 20, 20]);   // batch, 2 pixels
rgb.ycbcr([255, 0, 0], kb, kr);      // optional params keep their v2 place

Batch results are Float64Array, not Array — spread first if you need plain arrays.

2. Five spaces rescaled — the rest unchanged

Space	v2	v3
hsm	all 0–1	H 0–360, S 0–100, M 0–100
tsl	all 0–1	T 0–360, S 0–1, L 0–255
hsi	I 0–255	I 0–100
hcy	Y 0–255	Y 0–100 · reimplemented (the v2 formula was incorrect)
hsp	P 0–255, rounded outputs	P 0–100, exact

3. lab / lchab are D50 now

v2 lab was D65. v3 follows ICC / CSS Color 4: lab is D50, the v2 behavior lives on as lab-d65 / lch-d65. Declared bounds are truthful now (lab a/b ±125, luv u/v ±215) — metadata only, outputs identical.

4. min / max / channel / alias → range + data.json

space.rgb.range;   // [[0, 255], [0, 255], [0, 255]]

Channel names, refs, provenance: color-space/data.json. Aliases are gone — use canonical names.

5. ciecam and cubehelix removed; munsell works now

• ciecam (a one-way stub) → full bidirectional ciecam02, plus the CAM16 family.
• cubehelix is a colormap, not a space — removed, no replacement.
• v2 munsell was a broken stub; v3 implements the 1943 renotation bidirectionally.

6. Custom spaces connect both ways

import { register } from 'color-space';

const extended = register({
  name: 'unit-rgb',
  range: [[0, 1], [0, 1], [0, 1]],
  rgb: (r, g, b) => [r * 255, g * 255, b * 255],
}, {
  rgb: (r, g, b) => [r / 255, g / 255, b / 255],
});

Disconnected, duplicate and reserved names are rejected; neither input is mutated.

7. New since v2

162 spaces (v2: 41) · any-to-any by shortest path · lite / wasm / gl / lut / icc tiers · data.json, gamuts.js, whitepoints.js.

From v1 to v2

ESM only — for CJS use a bundler. require('color-space/rgb') → import rgb from 'color-space/rgb.js'.