US 12,440,098 B2
Method and system for glint-based eye detection in a remote eye tracking system
Hung-Son Lee, Danderyd (SE)
Assigned to Tobii AB, Danderyd (SE)
Filed by Tobii AB, Danderyd (SE)
Filed on Dec. 20, 2022, as Appl. No. 18/068,962.
Claims priority of application No. 2151597-8 (SE), filed on Dec. 22, 2021.
Prior Publication US 2023/0190096 A1, Jun. 22, 2023
Int. Cl. G06V 40/19 (2022.01); A61B 3/113 (2006.01); G06V 40/18 (2022.01)
CPC A61B 3/113 (2013.01) [G06V 40/19 (2022.01); G06V 40/193 (2022.01)] 17 Claims
OG exemplary drawing
 
1. A method for determining a position of at least one eye of a subject in images captured by a remote eye tracking system, the method comprising:
illuminating a face of a subject using at least one infrared (IR) illuminator off-axis from at least one image sensor;
capturing at least one image of the face using the at least one image sensor at a time instant; and
using a processing circuitry of the remote eye tracking system, performing processing steps of:
determining at least one pupil candidate associated with the at least one image;
determining at least one glint candidate associated with the at least one image, wherein the at least one glint candidate is determined by detection of a bright area of pixels in the at least one image;
determining at least one further glint candidate associated with the at least one image, wherein determining the at least one further glint candidate comprises determining an angle of a line between the at least one glint candidate and the at least one further glint candidate satisfying an angle of line threshold;
determining at least one pupil-glint candidate group, comprising at least one pupil candidate and at least one corresponding glint candidate;
generating a score value for each of the at least one pupil-glint candidate groups; and
determining an eye position of at least one eye of the subject in the at least one image based on the pupil-glint candidate group with the highest score value.