The daltoniser
Olivier Esser

A color blind simulator.

I have written an image viewer that can simulate the perception of the world that experience people with color deficiency. Unlike most of the tools seen on the web, this tool can also take the severity of the deficiency into account, with the help of a slider. It is able to simulate the most common forms of color blindness (Deuteranomaly, Propanomaly, Tritanomaly). This is a standalone Java desktop application that works like a simple image viewer, load any image on your computer and do the simulation. You can also save the altered image if you like.

The algorithm used is based on the research of Gustavo M. Machado, Manuel M. Oliveira and Leandro A. F. Fernandes (see their website where you will also find a reference to their research paper.)

New in v1.0. Adding a reverse simulation feature.  It is the recoloring that would bring the recolored image back to the original. Note that this only works within the limit of the color model. Doing the transformation in reverse might give a taste to mildly color deficient people of what normal vision people see. Please note that unlike the direct transformation, it is highly conjectural and is not supported by serious researchers. This should be considered as an experiment only.
v1.1. Change the background to black instead of white (white background could make the color less visible by saturating the eye. 

Installation and use

This software is written in Java. It has been tested in Windows 10 and GNU/Linux (ArchLinux). It is likely to work on Mac OS X or any platform that support Java. The recommended version is 8u121. Any later version is likely to work but previous versions (in particular the versions 7.x) will probably not work. You can download java from the Oracle website.

GNU/Linux users.

The software come as standalone jar that can be run with "java -jar daltoniser". It accepts an optional single file name argument. A simple optional shell script is given to launch it for convenience.

Windows users.

Provided that Java is correctly installed, you could run it by clicking on it. This tool does not write in the registry nor anywhere in your computer except to save the recolored image if you choose so.


zip file with the simulator and the license:
Source code (you only want it if you want to modify the software:
Previous releases are available here.

License and contact

This software is copyright by Olivier Esser (olivier dot esser at gmail dot com). It is available under the GPL version 2 (the text is contained in the package).

Bug and limitation.


Normal vision
Normal vision, the severity is set as 0.

Moderate deutan
Moderate deutan (the most common form of daltonism). The red poppies do not stand out that much but their red color is still clearly distinguishable from the green grass.

Strong deutan
Severe deutan. The red poppies meld completely with the green grass.
The picture on the screenshot is: By John Beniston (Palmiped), CC BY 3.0, Link