This online tool helps to solve two problems for people with colorblindness.
The first problem is that to a colorblind person a certain red will look identical to a certain green, even though to normal eyes the distinction is clear. This becomes a problem when a colorblind person has to delineate portions of an image from each other. A task which might be impossible if those areas happen to be “equal” values of green and red.
The second problem is that it is not easy for color-blind people to know how other people call a color. This is a problem if you have to understand color-coded signals or drawings, graphs or diagrams.
How this tool can help
To enable colorblind people to better see outlines on an image ColorBlinds.org provides an image daltonizer. Daltonize an image means to attempt to make colors more discernable to colorblind individuals by shifting the color spectrum.
Color blindness is usually related to the term red-green color blindness, which is interpreted as 'not being able to distinguish the colors red and green'. But this merely describes the most common form of color vision deficiency. The common types of color blindness are: Deuteranope (red/green color deficit), Protanope (another form of red/green color deficit) and Tritanope (a blue/yellow color deficit). The following images show how ColorBlind.org changes the color spectrum for each kind of color deficit.
Image optimized for Deuteranope
Image optimized for Protanope
Image optimized for Tritanope
To enable people to determine the hue and the name of a color this tool includes also a colorname picker. It identifies the color hue and name of the pixel under the mouse pointer.
To detect the name of a color move the mouse pointer over the daltonized or over the original image. The shown color name is always from the original image.
Note: This feature does currently not work in any Internet Explorer version.
Firefox ExtensionIf you are a regular user of colorblinds.org you might want to use the Firefox extension. With this extension you can right click on an image in firefox and choose "Open image on colorblinds.org". This will then open a new tab with the selected image. In the extension preferences you can specify which daltonize algorithmus you want to use.
Daltonizing an image is a computationally intensive process. Therefore we can not daltonize images of arbitrary sizes. If an image exceeds a specific size it will be scaled down, which will sometimes result in a small alteration of the original colors.
The automatic determination of a color name and hue of an image is not 100% reliable. Therefore use the results on your own risk.