关键词: 人脸检测, 运动向量, 疲劳判断, 光线补偿

Abstract: This paper proposes a multi-level face detection scheme.It successfully combines the face detection and tracking approach，and is used in a fatigue judging system.Firstly，process the image by compensating illumination to reduce the impact of illumination.Then calculate the similarity of the skin in the first image to remove the background and make the frame binaryzation.Then，the knowledge-based face detection is employed to get the information of face organs.Local processing is obtained in the next image corresponding region based on the face information obtained from the first image.Motion vector can be built from the information of the former two images.Using the motion vector，estimate the position of eyes in the following images and check the exact position.Finally，PERCLOS is used to analyze the face detection results and determine the status of fatigue.Experimental results show that the speed of the proposed face detection scheme is 2.5 times faster than the conventional methods，and the scheme can do a real-time tracking on eyes and has high detection accuracy.

Key words: face detection, motion vector, fatigue evaluation, illumination compensation