Web applications have become the most popular
type of software in the past decade, attracting the attention of
both the academia and the industry. In parallel with their
popularity, the complexity of aesthetics and functionality of web
applications have also increased significantly, creating a big
challenge for maintenance and cross-browser compliance testing.
Since such testing and verification activities require visual
analysis, web application testing has not been sufficiently
automated. In this paper, we propose a novel pairwise image
comparison approach suitable for web application testing where
the location of layout faults needs to be detected efficiently while
insignificant variations being neglected. This technique is
developed based on the characteristics of fault patterns of
browser layouts. An empirical study conducted with the industry
partner shows our approach is more effective and efficient than
existing methods in this area.