Color Blindness Simulator Revamped

It’s been a while since I touched my online color blindness simulator (read this post from 2005 for an overview of types of color blindness my tool supports and the algorithms behind it). Unfortunately, an elusive bug lurked in the calculations: once in a blue moon the tool would throw an exception on an integer overflow. I could never reproduce it or find the flaw in calculations.

Two readers of my blog asked to share the simulator as a stand-alone component. This prompted me to hunt down a more correct algorithm which is actually used in GIMP.

As an added benefit, the color blindness module I ported from GIMP also handles tritanopia (inability to discern blue and yellow). While at it, I heavily refactored my old, procedural code and extracted the simulator into a component of it own, as my readers requested. Feel free to grab the source code here.

Take a look at the output of two sample simulations of Toyota Matrix and Denver Airport produced by the new tool:

Looking forward to your feedback!