Method for determining a level of alertness of a driver

A method for determining a level of vigilance of a driver in a vehicle using a predetermined image-analyzing algorithm, said vehicle comprising a camera and a computer, said computer implementing said predetermined algorithm using at least one so-called “input” parameter relating to the attitude of the driver, the method comprising:

• generating, by the camera, a sequence of images of the head of the driver,
• executing the predetermined algorithm on said generated sequence of images in order to detect a series comprising at least one movement of the head of the driver,
• determining at least one value of at least one predetermined parameter relating to each movement of the detected series,
• comparing the at least one value of each parameter with a predetermined interval of values of said parameter, each predetermined interval of values of said parameter being associated with a different type of head movement,
• identifying each movement of the detected series using the at least one comparison made,
• determining the speed and/or amplitude of each identified movement,
• detecting dynamic and static periods of the head of the driver and measuring the frequency and the duration of each detected period, and
• determining a level of vigilance of the driver using the speed and/or amplitude determined for each identified movement and the frequency and duration of each detected period,
• wherein the driver is detected to be in an alert state when at least one rotation of the head of the driver to the right or to the left with respect to the Earth's vertical is determined in a predefined time window without notable degradation of the movement characteristics.

A computer of a vehicle for determining a level of vigilance of a driver of said vehicle using a predetermined image-analyzing algorithm, said vehicle comprising a camera, said computer implementing said predetermined algorithm using at least one input parameter relating to the attitude of the driver and being configured to:

• receive a sequence of images of the head of the driver, said sequence being generated by the camera,
• execute the predetermined algorithm on said received sequence of images in order to detect a series comprising at least one movement of the head of the driver,
• determine at least one value of at least one predetermined parameter relating to each movement of the detected series, wherein the at least one measured parameter comprises an angle of rotation of the head of the driver with respect to the Earth's vertical or an angle of inclination of the head of the driver with respect to the Earth's horizontal,
• compare the at least one value of each parameter with a predetermined interval of values of said parameter, each predetermined interval of values of said parameter being associated with a different type of head movement,
• identify each movement of the detected series using the at least one comparison made,
• determine the speed and/or amplitude of each identified movement,
• detect dynamic and static periods of the head of the driver and measure the frequency and duration of each detected period, and
• determining a level of vigilance of the driver using the speed and/or amplitude determined for each identified movement and the frequency and duration of each detected period,
• wherein the driver is detected to be in an alert state when at least one rotation of the head of the driver to the right or to the left with respect to the Earth's vertical is determined in a predefined time window without notable degradation of the movement characteristics.