Increasing Engagement With Virtual Agents Using Automatic Camera Motion

We describe a series of algorithms which automatically control camera position in a virtual environment while a user is engaged in a simulated face-to-face dialog with a single virtual agent. The common objective of the algorithms is to increase user engagement with the interaction. In our work, we describe three different automated camera control systems that: (1) control the camera's position based on topic changes in dialog; (2) use sentiment analysis to control the camera-to-agent distance; and (3) adjust the camera's depth-of-field based on "important" segments of the dialog. Evaluation studies of each method are described. We find that changing camera position based on topic shifts results in significant increases in a self-reported measure of engagement, while the other methods seem to actually decrease user engagement. Interpretations and ramifications of the results are discussed.