Subtle gaze-dependent techniques for visualising display changes in multi-display environments

This paper explores techniques for visualising display changes in multi-display environments. We present four subtle gaze-dependent techniques for visualising change on unattended displays called FreezeFrame, PixMap, WindowMap and Aura. To enable the techniques to be directly deployed to workstations, we also present a system that automatically identifies the user's eyes using computer vision and a set of web cameras mounted on the displays. An evaluation confirms this system can detect which display the user is attending to with high accuracy. We studied the efficacy of the visualisation techniques in a five-day case study with a working professional. This individual used our system eight hours per day for five consecutive days. The results of the study show that the participant found the system and the techniques useful, subtle, calm and non-intrusive. We conclude by discussing the challenges in evaluating intelligent subtle interaction techniques using traditional experimental paradigms.