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:
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.
Image obtained from : http://www.colblindor.com/2007/06/20/colorblindext-better-web-accessibility-for-colorblind-users/
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 run time environment.
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.
Source : http://www.colblindor.com/2007/06/20/colorblindext-better-web-accessibility-for-colorblind-users/