ColorBlindExt – Better Web Accessibility for Colorblind Users

Have you ever wondered, if you can’t see certain things on a website because of your color blindness? This time is over now—at least for colorblind Firefox users.

The Firefox add-on called ColorBlindExt was released just recently and is a great support to discover things which you couldn’t see up to now. The developers describe it as follows:

This extension helps color blinds while browsing the web, by processing images and text on the page according to the type of user’s color blindness. Color Blindness detection test is included for creating awareness among people.

After installation (see further down) as a first step you should take the color blindness test available through the newly added menu called ColorBlindExt. The test is based on Ishihara plates and will tell you, which type of color blindness you are suffering from. It detects protanopia, deuteranopia, tritanopia and even monochromacy, which means you are completely colorblind.

After taking the test the filter will be set according to your results. This can be changed at any time. Also the filter can be completely enabled or disabled however you like.

ColorBlindExt - Filtered Image
ColorBlindExt – Filtered Image

ColorBlindExt lets you choose to filter whole pages. This can be done either automatically or through the context menu, clicking with your right mouse button anywhere on the page and choose Filter page.

On the other side you can only filter images whereas a little window pops-up, showing you the filtered image by itself.

Personally I like the image filtering on demand. Through this option, which is also available on the context menu when clicking on an image, pictures and diagrams can be enhanced according to my type of color deficient vision.

The developers took the image filtering even one step further. Through the settings you even can adjust the level of deficiency and a choose from a noise reduction and sharpening option. This lets you play around and find the settings which fit the best to your personal color vision.

The tool also has some limitations, which don’t really restrict the usage to me when I look at them.

  • Page contents like flash objects, applets, media players can’t be filtered, it is out of scope.
  • Only elements accessed by DOM are processed.

Unfortunately the installation isn’t a single click and run. I tried to summarize all requirements including the links to get the latest software if you are missing some of them. I hope this helps you to get your colorblind webpage filter up and running without a hassle. Be aware that you need administration privileges if you have to install new software like the Java runtime environment.

Installing ColorBlindExt in 5 Steps

  1. Firefox
  2. Java Runtime Environment
  3. Java Advanced Imaging
    • Version: 1.1.3 or higher
    • Check: Start → Settings → Control Panel → Add or Remove Software
    • Download: – JAI for JRE
  4. Firefox User Registration
    • Why: ColorBlindExt is not yet available as a public download. It is accessible through the Firefox Add-ons sandbox, which is only open for registered users.
    • Registration Form: Firefox Add-ons: New User Registration
  5. ColorBlindExt

Hopefully this tool will help you to access some websites more easily than before or to read some colorful and up to now undistinguishable chart lines. And I also hope this tool isn’t used as an excuse for web designers to disregard accessibility, especially concerning color blindness.

2 responses on “ColorBlindExt – Better Web Accessibility for Colorblind Users

  1. Carstenq

    I still can’t install it although it seems to be public now :-( Installing the plugin results in a XUL/XML error next time I restart Firefox.