The amplitude of small eye movements can be accurately estimated with video-based eye trackers
(2023) In Behavior Research Methods 55(2). p.657-669- Abstract
- Estimating the gaze direction with a digital video-based pupil and corneal reflection (P-CR) eye tracker is challenging partly since a video camera is limited in terms of spatial and temporal resolution, and because the captured eye images contain noise. Through computer simulation, we evaluated the localization accuracy of pupil-, and CR centers in the eye image for small eye rotations (≪ 1 deg). Results highlight how inaccuracies in center localization are related to 1) how many pixels the pupil and CR span in the eye camera image, 2) the method to compute the center of the pupil and CRs, and 3) the level of image noise. Our results provide a possible explanation to why the amplitude of small saccades may not be accurately estimated by... (More)
- Estimating the gaze direction with a digital video-based pupil and corneal reflection (P-CR) eye tracker is challenging partly since a video camera is limited in terms of spatial and temporal resolution, and because the captured eye images contain noise. Through computer simulation, we evaluated the localization accuracy of pupil-, and CR centers in the eye image for small eye rotations (≪ 1 deg). Results highlight how inaccuracies in center localization are related to 1) how many pixels the pupil and CR span in the eye camera image, 2) the method to compute the center of the pupil and CRs, and 3) the level of image noise. Our results provide a possible explanation to why the amplitude of small saccades may not be accurately estimated by many currently used video-based eye trackers. We conclude that eye movements with arbitrarily small amplitudes can be accurately estimated using the P-CR eye-tracking principle given that the level of image noise is low and the pupil and CR span enough pixels in the eye camera, or if localization of the CR is based on the intensity values in the eye image instead of a binary representation. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/3b26588a-ae48-4093-a1cf-90787aa0f132
- author
- Nyström, Marcus LU ; Niehorster, Diederick C. LU ; Andersson, Richard LU ; Hessels, Roy S. and Hooge, Ignace T. C. LU
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Microsaccades, EyeLink 1000 plus, Image resolution
- in
- Behavior Research Methods
- volume
- 55
- issue
- 2
- pages
- 13 pages
- publisher
- Springer
- external identifiers
-
- scopus:85128175014
- pmid:35419703
- ISSN
- 1554-3528
- DOI
- 10.3758/s13428-021-01780-6
- language
- English
- LU publication?
- yes
- id
- 3b26588a-ae48-4093-a1cf-90787aa0f132
- date added to LUP
- 2022-04-14 09:54:57
- date last changed
- 2024-01-11 13:39:09
@article{3b26588a-ae48-4093-a1cf-90787aa0f132, abstract = {{Estimating the gaze direction with a digital video-based pupil and corneal reflection (P-CR) eye tracker is challenging partly since a video camera is limited in terms of spatial and temporal resolution, and because the captured eye images contain noise. Through computer simulation, we evaluated the localization accuracy of pupil-, and CR centers in the eye image for small eye rotations (≪ 1 deg). Results highlight how inaccuracies in center localization are related to 1) how many pixels the pupil and CR span in the eye camera image, 2) the method to compute the center of the pupil and CRs, and 3) the level of image noise. Our results provide a possible explanation to why the amplitude of small saccades may not be accurately estimated by many currently used video-based eye trackers. We conclude that eye movements with arbitrarily small amplitudes can be accurately estimated using the P-CR eye-tracking principle given that the level of image noise is low and the pupil and CR span enough pixels in the eye camera, or if localization of the CR is based on the intensity values in the eye image instead of a binary representation.}}, author = {{Nyström, Marcus and Niehorster, Diederick C. and Andersson, Richard and Hessels, Roy S. and Hooge, Ignace T. C.}}, issn = {{1554-3528}}, keywords = {{Microsaccades; EyeLink 1000 plus; Image resolution}}, language = {{eng}}, number = {{2}}, pages = {{657--669}}, publisher = {{Springer}}, series = {{Behavior Research Methods}}, title = {{The amplitude of small eye movements can be accurately estimated with video-based eye trackers}}, url = {{http://dx.doi.org/10.3758/s13428-021-01780-6}}, doi = {{10.3758/s13428-021-01780-6}}, volume = {{55}}, year = {{2023}}, }