JavaScript library for all kinds of color manipulations
chroma.deltaE
https://github.com/gka/chroma.js/pull/269
Before:
chroma.scale('RdYlGn').domain([0,1], 5).colors()
// returns ['#a50026', '#f88d52', '#ffffbf', '#86cb66', '#006837']
Now:
chroma.scale('RdYlGn').colors(5)