Image processing apparatus and drowsiness determination apparatus

The present invention aims to reduce the false detection of the eyelid from the face image. According to the present invention, the amount of change in the position of the eyelid contour candidate lines during blinking, whether they meet the normal eyelid movement is determined. If the amount of change in the position of the eyelid contour candidate line is determined not to conform to the movement of a normal eyelid in blinking, the eyelid contour candidate line is not set as the eyelid contour. Therefore, it is possible to reduce the erroneous detection of the eyelid from the face image.