ColorMap can help colour blind users in reading maps, seating plans and other content where colour is used to convey information.
Geography teachers can use ColorMap to make Choropleth maps accessible to colour blind students.
ColorMap is available in two versions:
Hover over the legend to see the map change. Alternatively, move focus to the map and then use the Arrow keys.
Step 1 of 2: Paste or drag an image to the box. Alternatively, upload a file.
Once you've dragged an image file to the box above, click on each of the colours in the legend, then hover the mouse over a legend item to see the corresponding colour turn black on the map. Alternatively, move focus to the map then use the Arrow keys to select a legend item.
Clicking on a legend item (or pressing the Enter key when it has focus) will freeze the map in this view so you can move the mouse without changing the view. This can help screen magnifier users as they use the mouse to navigate the screen. It also comes in handy for keyboard users as they can use the Arrow keys to scroll the page when the map is frozen.
Hovering over a legend and pressing the delete key removes the legend.
|Arrow||Move between legends|
|Enter||Freeze current legend|
|Delete||Remove current legend|
|Escape||Unselect current legend|
|B||Toggle black and white mode|
Clicking the lock button removes the ability to create new legends, so you can click around on the map as you wish.
The drop-down box can be used to change the colour tolerance. If the legend colour is different from the colour on the map it might be necessary to use a greater tolerance e.g. change the drop-down from 20 to 50 and then clicking to create a new legend.
Clicking the diamond icon shows a hue-saturation- lightness graph in the top left corner of the screen. The graph shows the colour of the pixel that is hovered over with the mouse.
Clicking the keyboard icon displays a yellow circle in center of the map. The circle can be moved using the keyboard Arrow keys and pressing Enter created a legend item on the map. This enables keyboard users to create legend items.
|Arrow||Move yellow circle one tenth of the map|
|Alt + Arrow||Move yellow circle 1 pixel|
|Shift + Arrow||Scroll webpage|
|Enter||Create a legend under yellow circle|
|C||Place yellow circle in the centre of the map and reset bisecting navigation|
|Ctrl + Arrow||Move yellow circle in bisecting distances: for each move the distance is halved|
|Escape||Exit keyboard mode|
This mode shows all legend pixels as black and all other pixels as white.
Tip: use the Down and Up arrow keys to cycle through legends and use the B key to toggle between standard view and black and white view.
The Show legends function creates a web page with images of the legends. This can be printed if a hardcopy is needed (you can print as PDF from browser). The content cannot be copied and pasted.
It can take a while to generate the print version. For large image files you might have to do one legend at the time and then combine the PDF documents.
This function works like "Show legends" except it downloads the web page to your Downloads folder. And, it doesn't work in IE.
The content can be copied and pasted e.g. into Word for editing.
If your browser shows a dialog box with "Open" and "Save" options, choose "Save".
The colourmap functionality can be added to any image by including a call to the colourmap function. On pageload, the image is swapped with a canvas element with built-in colourmap functions. This is shown in the demo at the top of the page.
Note: the webmaster version does not allow users to create or delete legend items.
You can get the ColourMap webmaster script from our Downloads page.
Code for making an image a colourmap:
The arguments to the addcolourmap function are:
Developed by Pierre Frederiksen. Pierre is a Principal Technical Consultant at Vision Australia
This software is being provided "as is", without any express or implied warranty. In particular, Vision Australia does not make any representation or warranty of any kind concerning the reliability, quality, or merchantability of this software or its fitness for any particular purpose. additionally, Vision Australia does not guarantee that use of this software will ensure the accessibility of your web content or that your web content will comply with any specific web accessibility standard.
This work is licensed under a Creative Commons License