Driver monitor and method for monitoring driver

A method for monitoring a driver, comprising:

• detecting the orientation and the position of the face of a driver of a vehicle from each of time-series face images representing the driver's face, the face images being obtained by a camera for capturing the driver, the camera being mounted on the vehicle;
• updating a reference direction of orientations of the driver's face, based on orientations of the driver's face respectively detected from face images obtained in a preceding predetermined period among the time-series face images, or updating a reference position of the driver's face, based on positions of the driver's face respectively detected from face images obtained in the predetermined period;
• detecting putting a wearable object on the driver's face or taking a wearable object off the driver's face in each of the time-series face images,
• wherein the updating includes updating, upon detection of putting on or taking off the wearable object, the reference direction, based on only orientations of the driver's face detected from face images obtained after the detection among the time-series face images, or updating the reference position, based on only positions of the driver's face detected from face images obtained after the detection;
• storing, upon detection of putting on the wearable object, a first reference direction or a first reference position of the driver's face at detection of putting on the wearable object in a memory before resetting the reference direction or the reference position;
• and
• setting, upon subsequent detection of taking off the wearable object, the first reference direction or the first reference position stored in the memory as the reference direction or the reference position of the driver's face at detection of taking off the wearable object.

A driver monitor comprising:

• a processor configured to:
• detect the orientation and the position of the face of a driver of a vehicle from each of time-series face images representing the driver's face, the face images being obtained by a camera for capturing the driver, the camera being mounted on the vehicle,
• update a reference direction of orientations of the driver's face, based on orientations of the driver's face respectively detected from face images obtained in a preceding predetermined period among the time-series face images, or update a reference position of the driver's face, based on positions of the driver's face respectively detected from face images obtained in the predetermined period, and
• detect putting a wearable object on the driver's face or taking a wearable object off the driver's face in each of the time-series face images;
• wherein:
• upon detection of putting on or taking off the wearable object, the processor is configured to update the reference direction, based on only orientations of the driver's face detected from face images obtained after the detection among the time-series face images, or update the reference position, based on only positions of the driver's face detected from face images obtained after the detection, and
• the processor is further configured to:
• exclude one or more face images for which an absolute value of a difference between:
• (i) a detected face orientation or a detected face position in the one or more face images and (ii) the updated reference direction or the updated reference position, respectively, is beyond a predetermined tolerable range, and
• again update the reference direction or the reference position based on the face images obtained after the detection except for the one or more face images that have been excluded.

A method for monitoring a driver, comprising:

• detecting the orientation and the position of the face of a driver of a vehicle from each of time-series face images representing the driver's face, the face images being obtained by a camera for capturing the driver, the camera being mounted on the vehicle;
• updating a reference direction of orientations of the driver's face, based on orientations of the driver's face respectively detected from face images obtained in a preceding predetermined period among the time-series face images, or updating a reference position of the driver's face, based on positions of the driver's face respectively detected from face images obtained in the predetermined period;
• and
• detecting putting a wearable object on the driver's face or taking a wearable object off the driver's face in each of the time-series face images, wherein
• the updating includes:
• updating, upon detection of putting on or taking off the wearable object, the reference direction, based on only orientations of the driver's face detected from face images obtained after the detection among the time-series face images, or updating the reference position, based on only positions of the driver's face detected from face images obtained after the detection;
• excluding one or more face images for which an absolute value of a difference between:
• (i) a detected face orientation or a detected face position in the one or more face images and (ii) the updated reference direction or the updated reference position, respectively, is beyond a predetermined tolerable range;
• and
• again updating the reference direction or the reference position based on the face images obtained after the detection except for the one or more face images that have been excluded.