基于DM642的嵌入式疲劳驾驶监测系统的实现

Implementation of embedded real-time driving fatigue monitoring system based on DM642

针对基于DM642的嵌入式疲劳驾驶监测系统,讨论了系统的总体结构,提出了采用可控光源、奇偶差分帧和人眼跟踪的人眼检测方法。在与奇偶帧图像采集同步的内外圈光源的照射下,利用近轴光源的红眼效应,引起图像奇帧暗瞳孔、偶帧亮瞳孔,由奇偶差分帧快速实现人眼检测与跟踪。同时分析眼睛的特征参数,在一定时间内连续统计眼睛的闭合时间,计算眼睛累计闭合持续时间占某特定时间的百分率(PERCLOS)值来判断疲劳程度并报警。该系统疲劳监测准确率较高,可在汽车驾驶中进行实时疲劳驾驶监测。

The major frame of the real-time embedded driving fatigue monitoring system based on DM642 was discussed. A method of eye detection was presented by using controllable LEDs and differences of odd-even frames. In this method, the odd and even frames were captured respectively through synchronizing the inner and outer ring of LEDs. Because of the redeyed effect generated by adaxial LEDs, one frame had bright pupils and the other had dark pupils. Therefore, the pupils were easy to be detected and tracked from the difference of the two frames. Then the characteristic parameters of eyes could be analyzed. After that, the closing time of eyes within regular successive time was counted. Finally the percentage of eyelid closure over the pupil over time （PERCLOS） value was calculated, and the tiring degree of driver could be judged and alarmed when necessary. Experimental results show that the fatigue detection rate in tiffs system is high, and it can be used to monitor the driver＇s fatigue state.