Evaluating the Influence of Room Illumination on Camera-Based Physiological Measurements for the Assessment of Screen-Based Media

Camera-based solutions can be a convenient means of collecting physiological measurements indicative of psychological responses to stimuli. However, the low illumination playback conditions commonly associated with viewing screen-based media oppose the bright conditions recommended for accurately recording physiological data with a camera. A study was designed to determine the feasibility of obtaining physiological data, for psychological insight, in illumination conditions representative of real world viewing experiences. In this study, a novel method was applied for testing a first-of-its-kind system for measuring both heart rate and facial actions from video footage recorded with a single discretely-placed camera. Results suggest that conditions representative of a bright domestic setting should be maintained when using this technology, despite this being considered a sub-optimal playback condition. Further analyses highlight that even within this bright condition, both the camera-measured facial action and heart rate data contained characteristic errors. In future research, the influence of these performance issues on psychological insights may be mitigated by reducing the temporal resolution of the heart rate measurements and ignoring fast and low-intensity facial movements.