Finding an Efficient Threshold for Fixation Detection in Eye Gaze Tracking
We propose a combined analytical/statistical method to determine an efficient threshold on the dispersion of estimates of the point of gaze (POG) to indicate a user fixation. The experimental data for this study was obtained with an EyeTech TM3 eye gaze tracker (EGT). The experimental protocol to make the user fixate on pre-determined visual targets was implemented using the C language and OpenCV. Subjects first used the system in a training mode, from which an individualized dispersion threshold was obtained. Our approach was verified by applying the individualized threshold to POG data from a second run, in testing mode, with encouraging results.
KeywordsFixation identification Eye gaze tracking Data analysis algorithm
This material is based in part upon work supported by the National Science Foundation under Grant Nos. I/UCRC IIP-1338922, AIR IIP-1237818, SBIR IIP-1330943, III-Large IIS-1213026, MRI CNS-1532061, OISE 1541472, MRI CNS-1532061, MRI CNS-1429345, MRI CNS-0821345, MRI CNS-1126619, CREST HRD-0833093, I/UCRC IIP-0829576, MRI CNS-0959985, RAPID CNS-1507611.
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