Assessing Cartographic Products for Visual Usability - Modern Trends in Cartography - page 264

This feature is delivered as part of the Ordnance Survey product OS VectorMap

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Local (Ordnance Survey 2009 ).

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Guidelines and Tools

General Web accessibility guidelines are published under Web Content Accessi-
bility Guidelines (WCAG). Also, Checkpoint 2.2 of the guidelines requires that
foreground/background colour schemes must have sufficient contrast when viewed
by someone with colour vision defects or viewed on a black and white screen.
A number of tools exist to simulate how colour-blind users would see maps and
other tools that assist in choosing appropriate thematic mapping colour schemes to
ensure inclusiveness.

￿ Color Oracle is a free Java tool (Windows, Linux and Mac) developed by Dr
Bernhard Jenny, of ETH Zurich, Switzerland. It can be used for evaluating the
effects of several kinds of colour blindness. http://colororacle.cartography.ch/
(Authors note: the author was the second supervisor of Dr Jenny

s Ph.D.).
￿ Color Brewer ( www.colorbrewer.org ) generates GIS colour schemes that are
distinguishable by users who are colour-blind (Nugent 2011 ). The site provides
schemes that are

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to colour-blind users.
￿ Colour Vision ( www.iamcal.com/toys/colors/ ) provides a tool for simulating
colour deficiencies.
￿ Colorblind Web Page Filter ( http://colorfilter.wickline.org/ ) is a tool for
checking Web pages for colour deficient or colour-blind users. A Web site
URL is input into the package and the simulation is automatically generated
online.
￿ Colour-blindness Simulator ( http://www.etre.com/tools/colourblindsimulator/ )
uses an uploaded JPEG image (

friendly

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100 kb) to generate
a new image, simulating how a colour-blind person would see the image.
￿ Colour Check ( http://www.etre.com/tools/colourcheck ) checks colours for con-
formance to the WCAG (Web Content Accessibility Guidelines). It determines
the colour difference and contrast between any two colours chosen for back-
ground/foreground applications.
￿ Colourmaps ( www.tsi.enst.fr/~brettel/CRA24/fig3java.html ) for checking the
legibility of displays by dichromats,
￿ Safe Web colors for colour-deficient vision ( http://www.btpic.com/age_
disabiity/technology/RandD/colours/index.htm )—translations, definitions, etc.
￿ What do colour-blind people see? ( http://www.tsi.emst.fr/~brettel/
colourblindness.html ) is an interactive java applet that demonstrates colour-
blindness for protanopia and deuteranopia.
￿ Vischeck ( www.vischeck.com ) is a resource for information about colour-
blindness. Map designers are able to upload an image file and Vischeck simu-
lates how the map would appear to a colour-blind person. The real limitation of

1,000 1,000 pixels and

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