Color versus Texture Coding to Improve Visual Search Performance

An experiment is reported in which the relative effectiveness of color coding, texture coding, and no coding of target borders to speed visual search is determined. The following independent variables were crossed in a within-subjects factorial design: Color coding (present or not), Texture coding (present or not), Distance between similarly coded targets (near or far), Group size of similarly coded targets (1, 2, 3, or 4), and a Replication factor of target Border width (10, 20, or 30 pixels). Search times, errors, and subjective rankings of the coding methods were recorded. Results showed that color coding improved search time compared to no coding, but that texture coding was not effectively used by subjects, resulting in nearly identical times to uncoded targets. Subjective preference rankings reflected the time data. The adequate power of the experiment along with the results of preparatory pilot studies lead us to the conclusion that texture coding is not an effective coding method for improving visual search time.