Abstract: The background information, such as life burden, work load and sleep quality, plays a very important role in mental fatigue recognition based on facial visual cues,however,they cannot be directly extracted from facial video. Based on the theory,ideals and methods of extenics,combined with some classic mathematical methods and existing computer vision technology, this paper proposed a new mental fatigue extension recognition model. Based on the idea of contradic- lions transformation, the background information which cannot be directly extracted from the facial video is translated into the corresponding facial fatigue appearance in the model,and the facial fatigue appearance can be directly extracted from the facial video. And this model also proposes a fusion approach for existing facial fatigue visual cues and facial fa- tigue appearance to recognize mental fatigue. hhe experimental results verify the validity of the model.

Key words: Mental fatigue recognition model, Extension set, Extension transformation, Facial fatigue, Correlation function