Color Schemes for Encoding Information in Digital Maps

Color schemes have been used in maps to visually distinguish different regions or to approximately represent the magnitude of a property. Since human eyes are not able to translate a color to a numerical scale, colors on a traditional map can only be used to visually estimate magnitudes. As maps are represented more and more digitally, a properly designed color scheme may be able to use color to encode numbers and to accurately translate colors into numerical scales of a property. As a mouse (or other pointers) points to a location, the color of the location can be translated into the original encoded number and therefore the numerical property of the location may be displayed. In this paper, method to encode information in digital maps using color schemes is investigated. A hue-based color scheme was developed to encode and decode numerical scales for digital maps. Color gamut issues between display and print are investigated as well.