Mobile eye tracking system

A method for providing computer input by tracking a direction of a gaze of an eye, the method comprising:

• providing a computing device;
• providing a monitor of the computing device, the monitor having an indication marking an identifying region of the monitor;
• mounting a first camera to a user and positioning a lens of the first camera to face generally in a direction of the field of view of the user to collect scene information;
• mounting a second camera to the user and positioning a lens of the second camera to face toward an eye of the user to collect information relating to a direction of a gaze of an eye;
• using the scene information collected from the first camera to determine a location of the identifying region of the monitor;
• using the information collected from the second camera to determine the direction of the gaze of the eye;
• and
• providing input to the computing device based on the direction of the gaze of the eye.

At least one non-transitory computer storage medium comprising computer-executable instructions that, when executed by at least one processor, perform a method for calculating a location of a center of a pupil of an eye, the method comprising:

• a) generating an image of a pupil of an eye comprising a distribution of pixels, each pixel having an intensity value and a geometric position on the image;
• b) selecting pixels having intensity values that fall within a defined range of intensity values;
• c) determining an average geometric position of the pixels having intensity values that fall within the defined range, the average geometric position being a first starting point for determining a location of a center of the pupil of the eye on the image;
• d) making measurements of a value of pixel intensity along lines extending in a plurality of directions away from the starting point;
• e) for each of the lines extending away from the starting point, determining a stop point, each stop point being determined based on a pixel intensity change exceeding a first threshold;
• f) for each stop point, making measurements of a value of pixel intensity along lines extending in a plurality of directions from the stop point back toward the starting point and at a plurality of points adjacent to the starting point;
• g) for each line from the stop point back to the starting point and a plurality of points adjacent to the starting point, defining a feature point having a geometric position, each feature point being determined based on a pixel intensity change exceeding second threshold;
• and
• h) averaging the geometric positions of the feature points to calculate a second starting point for determining the location of the center of the pupil of the eye on the image.

A method for estimating a location of a center of a pupil of an eye from an image of the eye having pixels, the method comprising:

• generating an image of a pupil of an eye comprising a distribution of pixels, each pixel having an intensity value and a geometric position on the image;
• selecting pixels having intensity values that fall within a defined range of intensity values;
• determining the geometric positions of the pixels having intensity values that fall within the defined range of intensity values;
• determining an average geometric position of the pixels having intensity values that fall within the defined range, the average geometric position being a first starting point for determining a location of a center of the pupil of the eye on the image;
• making measurements of a value of pixel intensity along lines extending in a plurality of directions away from the starting point;
• for each of the lines extending away from the starting point, determining a stop point, each stop point being determined based on a pixel intensity change exceeding a first threshold;
• for each stop point, making measurements of a value of pixel intensity along lines extending in a plurality of directions from the stop point back toward the starting point and at a plurality of points adjacent to the starting point;
• for each line from the stop point back to the starting point and a plurality of points adjacent to the starting point, defining a feature point having a geometric position, each feature point being determined based on a pixel intensity change exceeding a second threshold;
• and
• averaging the geometric positions of the feature points to calculate a second starting point for determining the location of the center of the pupil of the eye on the image.

A mobile eye tracking system, the system comprising:

• an identifying region of a field of view, the identifying region being recognizable by an indication;
• a computing device programmed to recognize the indication of the field of view;
• a first camera adapted to collect information related to a location of the identifying region of the field of view based on the indication of the identifying region, the first camera being adapted to be mounted to a user such that a lens of the first camera faces away from the user;
• and
• a second camera adapted to collect information through a lens from the eyes from which a direction of a gaze of an eye of the user may be determined, the lens being adapted to be disposed in close proximity to and facing an eye of the user, the information collected from the second camera being provided as an input to the computing device.

A method for providing computer input based upon a direction of a gaze of an eye of a user, the method comprising:

• providing an indication marking an identifying region of a field of view;
• mounting a first camera to the user and positioning a lens of the first camera to face away from the user to collect scene information;
• mounting a second camera to the user and positioning a lens of the second camera to face the eye of the user to collect information from the eye from which a direction of gaze of the eye may be determined;
• determining a location of the identifying region of the field of view from the indication based upon the scene information collected from the first camera;
• determining the direction of the gaze of the eye using the information collected from the second camera;
• and
• providing an input to the computing device based on a location of an intersection of the direction of the gaze of the eye and the identifying region of the field of view.