Automatic exposure and white balance control in video cameras: Time course characterization and preference

On a coarse level the lightness and chromatic adaptation of the human visual system (HVS) and signal processing in a video camera are comparable processes. Both adapt to changes in lighting environment and are time dependent. This study developed metrics for characterizing time-course of automatic exposure (AE) and white balance (AWB) controls in video cameras. To evaluate subjective preference for AE and AWB videos, specific scenes with natural lighting changes were designed. Our results show that the subjective preference AE time course is fast and without overshoot. In addition preference speed for the time-course of AWB was about six seconds for videos used in this study.