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Sim Daltonism for Mac and iOS


Sim Daltonism is a color blindness simulator for iOS and Mac. It takes a live video feed from the camera on iOS and filters it in real time using a color blindness simulation algorithm.

The Mac version has a filter window that shows the content underneath the window filtered.

The application is almost a clone of Red Stripe where the filter algorithm has been replaced with an OpenGL adaptation of the color_blind_sim javascript function found on the Color Laboratory. The video capture and live filtering code is taken in part from the RosyWriter sample code provided by Apple.

This application shares a lot with my other app Red Stripe. Note that contribution accepted in Sim Daltonism will often land into Red Stripe too, which is closed source.

Copyright & License

Sim Daltonism
© 2005-2020 Michel Fortin

Includes the color blindness simulation algorithm color_blind_sim.
© 2000-2001 Matthew Wickline and the Human-Computer Interaction Resource Network

Sim Daltonism is available under the Apache 2.0 License. See the Apache License 2.0.txt file for the complete terms. Additional license terms apply to the color blindness simulation algorithm as follow:

The color_blind_sims() JavaScript function in the is
copyright (c) 2000-2001 by Matthew Wickline and the
Human-Computer Interaction Resource Network ( ).

The color_blind_sims() function is used with the permission of
Matthew Wickline and HCIRN, and is freely available for non-commercial
use. For commercial use, please contact the
Human-Computer Interaction Resource Network ( ).
(This notice constitutes permission for commercial use from Matthew
Wickline, but you must also have permission from HCIRN.)
Note that use of the color laboratory hosted at does
not constitute commercial use of the color_blind_sims()
function. However, use or packaging of that function (or a derivative
body of code) in a for-profit piece or collection of software, or text,
or any other for-profit work *shall* constitute commercial use.

20151129 UPDATE
	HCIRN appears to no longer exist. This makes it impractical
	for users to obtain permission from HCIRN in order to use
	color_blind_sims() for commercial works. Instead:

	This work is licensed under a
	Creative Commons Attribution-ShareAlike 4.0 International License.

A note about that license

The copyright for the original color blindness simulation algorithm is shared by Matthew Wickline and the Human-Computer Interaction Resource Network. It seems the HCIRN is not reachable anymore, and it probably no longer exists. Because of this, Matthew Wickline decided to to change the license to something he believed would reflect the original intent of the HCIRN. But it is possible that someone still owns the HCIRN copyright, which would make that license change legally contestable.

So I am relying solely on the older non-commercial clause for distributing this app.

If you distribute a derived work that does not include the color blindness simulation algorithm derived from color_blind_sim, then you only have to follow the terms of the Apache License 2.0.