dichromacy

Simulate the three dichromacies — protanopia, deuteranopia, tritanopia. A color or a whole image as a dichromat (missing one cone type) sees it.

npm install dichromacy

const dichromacy = require("dichromacy");
dichromacy.simulate("#d7191c", "deutan");   // that red to a deuteranope
dichromacy.protan("#1a9641");               // green to a protanope
const png = dichromacy.simulateImage("./chart.png", "tritan");

• simulate(color, type, severity?) → hex. type is "protan", "deutan", or "tritan".
• simulateImage(input, type, opts?) → a recolored PNG Buffer.
• protan/deutan/tritan(color, severity?) → the named shortcuts.

An umbrella over cvdsim (Machado, Oliveira & Fernandes 2009). For total color blindness see achromatopsia; for mild vision see trichromacy. A simulation, not a diagnosis.

Licence

MIT.