Head pose coordinate system axes position and orientation. 

Head pose coordinate system axes position and orientation. 

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Automatic gaze estimation not based on commercial and expensive eye tracking hardware solutions can enable several applications in the fields of human computer interaction (HCI) and human behavior analysis. It is therefore not surprising that several related techniques and methods have been investigated in recent years. However, very few camera-bas...

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... problem. For more details, see [51]. The next step in our algorithm is the estimation of the vector T from the origin of the camera reference frame to a reference frame centered at the user's face. More precisely, the head pose reference system has its origin centered at the nose base and x-, y-axes parallel to the mouth and nose, respectively (Fig. 3). The rotation matrix R between the head pose and the camera reference system is pro- duced by IntraFace. In order to compute T, we assume a fixed distance D = 90 mm between the external corners of the eye contours and a fixed distance H = 70 mm from a point at the bottom of the nose (nose base) and the seg- ment joining the two pupils ...

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