Contributions on color perception earn Brooks Best Paper at CHI

A paper co-authored by UMSI assistant research professor Christopher Brooks has received a Best Paper award ahead of the ACM CHI 2016 conference. 

“Enabling Designers to Foresee Which Colors Users Cannot See” was co-authored by University of Washington assistant professor Katharina Reinecke, University of Dundee lecturer and fellow David R. Flatla and Brooks. The paper describes the development of a tool that increases accessibility by helping designers check how color choices will affect users.

Different situations, such as dim lighting or bright sunlight, can affect the ability of users to differentiate between colors on screens. Different users also have different internal abilities to differentiate between colors. However, designers do not have a tool to take these differences into account. 

The researchers aimed to experimentally determine how such a tool could be developed. To do this, they created an open-source color differentiation test, WebCDT, that measures users’ color differentiation abilities. They then conducted a controlled lab study to show that the tool is sensitive to changes in environmental lighting and analyzed differences in people’s color vision based on crowdsourced input from nearly 30,000 participants.

The researchers used the results of this analysis to develop a tool, ColorCheck, that enables designers to see what proportion of a population is included (or excluded) by the color choices the designers make. ColorCheck works by comparing pairs of colors in a color space and telling designers what proportion of an image’s colors are differentiable for a certain proportion of the population. The software also layers a mask of black pixels over an image to indicate trouble spots.

Above: Images from the paper demonstrate how the software shows designers which parts of their designs might be undifferentiable.

This allows designers to see if key parts of their designs—for example, color-coded graphics—will be perceivable by their target viewers. The designer can then use this information to make decisions about whether to change their color choices.

In addition to developing the ColorCheck tool, researchers found that deficits in color differentiation ability are more widespread than previously assumed, suggesting that large numbers of users might experience problems with usability, comprehension of graphic material or aesthetics. 

“We have demonstrated that color choices can limit the ability of large proportions of users to perceive images as the designer intended,” the researchers said. “With laptops and mobile devices becoming increasingly ubiquitous, we believe that it is time digital content is designed accordingly.”

Best Paper awards go to the top one percent of accepted papers at CHI, the top international conference on Human-Computer Interaction. The authors will present their paper on Tuesday, May 10, at 2:30 pm at the 2016 CHI conference in San Jose, California.

Posted May 4, 2015