PERCLOS

PERCLOS, which stands for PERcentage of Closed EYES, is a measure used in the field of drowsy driver detection. It quantifies the degree of eyelid closure over a given period, serving as an indicator of driver fatigue. The system typically employs computer vision techniques to analyze video feeds from a camera focused on the driver's face. Algorithms track key facial landmarks, particularly around the eyes, to calculate the proportion of time the eyelids are shut. A higher PERCLOS value suggests increased drowsiness.

PERCLOS is often used in conjunction with other metrics, such as head pose and yawning frequency, to build a comprehensive driver state monitoring system. Higher PERCLOS values are correlated with a reduced ability to maintain a safe driving posture and a slower reaction time, both critical factors in preventing accidents. Research has shown PERCLOS to be a reliable indicator of fatigue, with studies demonstrating its effectiveness in distinguishing between alert and drowsy drivers. The development of PERCLOS-based systems aims to enhance road safety by providing early warnings to drivers when they are at risk of falling asleep at the wheel.