Measuring torsional eye movements by tracking stable iris features.
Bottom Line: In this method, we track iris features that have been identified as Maximally Stable Volumes.These features, which are stable over time, are dark regions with bright borders that are steep in intensity.The advantage of Maximally Stable Volumes is that they are robust to nonuniform illumination and to large changes in eye and camera position.
Affiliation: Institute of Medical Device Engineering, FH OO Forschungs & Entwicklungs GmbH, Upper Austria University of Applied Sciences, Garnisonstr 21, 4020 Linz, Austria. firstname.lastname@example.orgShow MeSH
Related in: MedlinePlus
Mentions: To develop the method, we recorded videos with the EyeSeeCam (Dera et al., 2006), a portable head-mounted video-oculography system. Our videos were recorded in the uncompressed Portable Graymap Format at 130 Hz in 8-bit greyscale. Each frame was 348 by 216 pixels in size, with a resolution of roughly 15 pixels/mm at the plane of the cornea (see Fig. 1 for an example image). However, we have tested the method with videos recorded with other systems, and the method described below also works on those videos after we account for the different image resolution, image quality, and sampling rate. Indeed, part of the validation described in this paper is performed with a Basler A602fc high speed camera, recording at 100 Hz.
Affiliation: Institute of Medical Device Engineering, FH OO Forschungs & Entwicklungs GmbH, Upper Austria University of Applied Sciences, Garnisonstr 21, 4020 Linz, Austria. email@example.com