We present a video-based monitoring system to determine the sleep status and optimal wakeup time in this paper. We envision a smart living space in which a data collection and processing module named iWakeUp is installed in the bedroom to record and monitor sleep in a non-invasive manner. We describe the overall structure of the iWakeUp system, including the procedure to measure amount of motion, the method for inferring wake/sleep status from the acquired video and the logic for deciding the optimal wakeup time. In particular, a time-dependent decision rule has been incorporated to account for unequal penalties when classification error occurs. Validation experiments have been carried out to compare alertness levels upon awakening with/ without the assistance of iWakeUp. It was found that participants using iWakeUp reported a lower level of sleepiness and higher level of vigor in comparison to the control group. The proposed iWakeUp module has been integrated into the Sleep Coach system which is currently under extensive field tests to validate its efficacy and efficiency in practical situations.
Journal of the Chinese Institute of Engineers, Transactions of the Chinese Institute of Engineers,Series A/Chung-kuo Kung Ch'eng Hsuch K'an, 33(5), 661-668