Driver condition detection system

A driver condition detection system comprising:

• a driver monitor camera capturing a face of a driver of a vehicle and generating a facial image of the driver, and
• a driver condition detection part configured to detect a condition of the driver based on the facial image, wherein
• when a part of face parts of the driver is hidden in the facial image, the driver condition detection part is configured to detect a condition of the driver based on each of face parts of the driver not hidden in the facial image, the face parts of the driver being a mouth, nose, right eye, and left eye of the driver,
• the condition of the driver is a facial direction of the driver,
• when a part of the face parts of the driver is hidden in the facial image, the driver condition detection part is configured to detect the facial direction of the driver based on the face parts of the driver not hidden in the facial image and the facial image before a part of the face parts of the driver is hidden, and
• the driver condition detection part is configured to judge that the facial direction of the driver has not changed from before a part of the face parts of the driver was hidden when an amount of change of a condition of the face parts of the driver not hidden in the facial image is a threshold value or less, and not detect the facial direction of the driver when the amount of change is larger than the threshold value.