The use of video-based eye trackers (VETs) for gaze interaction have allowed people with severe motor disabilities to communicate more effectively. Nonetheless, current low cost VETs present limited accuracy and precision that impose several design constraints for gaze-based computer applications. In this paper we present an extension of the differential lighting (DL) technique for pupil detection and tracking using active light sources. The original technique was developed for analog interlaced cameras with external sync signal to synchronize the light sources with the video signal. In this paper we introduce the Stroboscopic DL technique that can be used with any rolling shutter camera, even those with no external sync. We have developed a computer vision technique to adjust the firing of the stroboscopic lights. Our new algorithm also exploits characteristics of pupil images to improve the accuracy of the tracking algorithm. Another advantage of the method is that using flashed pulses of light creates a virtual exposure time, reducing motion blur and temporal shear in the video volume. A real-time 187 fps prototype of the system was implemented using a low cost PS3 camera. Experimental results comparing the performance of our algorithm with Starburst show significant accuracy and speed improvement.
BibTeX
@inproceedings{Borsato:2015,
author = {Frank H. Borsato and Fernando O. Aluani and Carlos H. Morimoto},
booktitle = {2015 IEEE International Conference on Computer Vision Workshop (ICCVW)},
title = {A Fast and Accurate Eye Tracker Using Stroboscopic Differential Lighting},
year = {2015},
pages = {502-510},
keywords = {cameras;gaze tracking;image restoration;motion estimation;synchronisation;video signal processing;PS3 camera;VET;active light source synchronization;analog interlaced cameras;computer vision technique;external sync signal;flashed light pulses;gaze interaction;gaze-based computer applications;motion blur reduction;motor disabled people communication;pupil detection;pupil tracking;rolling shutter camera;stroboscopic DL technique;stroboscopic differential lighting;temporal shear reduction;video signal;video volume;video-based eye trackers;virtual exposure time;Cameras;Clocks;Estimation;Light sources;Lighting;Synchronization;Tracking},
doi = {10.1109/ICCVW.2015.72},
month = {December},
}