{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T00:36:43Z","timestamp":1771029403466,"version":"3.50.1"},"reference-count":70,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,15]],"date-time":"2021-10-15T00:00:00Z","timestamp":1634256000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Remote eye tracking technology has suffered an increasing growth in recent years due to its applicability in many research areas. In this paper, a video-oculography method based on convolutional neural networks (CNNs) for pupil center detection over webcam images is proposed. As the first contribution of this work and in order to train the model, a pupil center manual labeling procedure of a facial landmark dataset has been performed. The model has been tested over both real and synthetic databases and outperforms state-of-the-art methods, achieving pupil center estimation errors below the size of a constricted pupil in more than 95% of the images, while reducing computing time by a 8 factor. Results show the importance of use high quality training data and well-known architectures to achieve an outstanding performance.<\/jats:p>","DOI":"10.3390\/s21206847","type":"journal-article","created":{"date-parts":[[2021,10,17]],"date-time":"2021-10-17T23:25:15Z","timestamp":1634513115000},"page":"6847","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Accurate Pupil Center Detection in Off-the-Shelf Eye Tracking Systems Using Convolutional Neural Networks"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8075-2426","authenticated-orcid":false,"given":"Andoni","family":"Larumbe-Bergera","sequence":"first","affiliation":[{"name":"Arrosadia Campus, Public University of Navarre, 31006 Pamplona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3635-6530","authenticated-orcid":false,"given":"Gonzalo","family":"Garde","sequence":"additional","affiliation":[{"name":"Arrosadia Campus, Public University of Navarre, 31006 Pamplona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3687-4477","authenticated-orcid":false,"given":"Sonia","family":"Porta","sequence":"additional","affiliation":[{"name":"Arrosadia Campus, Public University of Navarre, 31006 Pamplona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7999-1182","authenticated-orcid":false,"given":"Rafael","family":"Cabeza","sequence":"additional","affiliation":[{"name":"Arrosadia Campus, Public University of Navarre, 31006 Pamplona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9822-2530","authenticated-orcid":false,"given":"Arantxa","family":"Villanueva","sequence":"additional","affiliation":[{"name":"Arrosadia Campus, Public University of Navarre, 31006 Pamplona, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1124","DOI":"10.1109\/TBME.2005.863952","article-title":"General theory of remote gaze estimation using the pupil center and corneal reflections","volume":"53","author":"Guestrin","year":"2006","journal-title":"IEEE Trans. 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