The use of a single uncalibrated camera is desirable for eye tracking to reduce the overall complexity and cost of the system. Quite often, at least one external light source is used to enhance image quality and generate a corneal reflection used as a reference point to estimate the point-of-gaze (PoG). Though the use of more than one light source has shown to enhance accuracy and robustness to head motion, it is unlikely that all corneal reflections appear in the eye images during natural eye movements. In this paper, we introduce the Screen-Light Decomposition (SLD) framework as a generalized model for PoG estimation using a single uncalibrated camera and a variable number of light sources. SLD synthesizes existing uncalibrated video-based eye trackers and can be used as a modeling tool to compare and design eye trackers. We have used the framework to design a novel eye-tracking technique, called SAGE, for single normalized space adaptive gaze estimation, that can gracefully degrade the gaze tracker performance when one or more corneal reflections are not detected, even during the calibration procedure. Results from an user experiment are presented to demonstrate its improved performance over other designs.
BibTeX
@article{Morimoto:JMIV2020,
title = {Screen-Light Decomposition Framework for Point-of-Gaze Estimation Using a Single Uncalibrated Camera and Multiple Light Sources},
issn = {1573-7683},
url = {https://doi.org/10.1007/s10851-020-00947-8},
doi = {10.1007/s10851-020-00947-8},
journal = {Journal of Mathematical Imaging and Vision},
publisher={Springer},
date = {2020-02-15},
volume={62},
number={4},
pages={586-605},
year={2020},
author = {Morimoto, Carlos H. and Coutinho, Flávio L. and Hansen, Dan W.}
}