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: The final step of our validation involved applying our torsional tracking method to a video of macaque iris, which was recorded in the infrared. Such videos are typically considered to be almost featureless, but nonetheless, our method was able to find features on the iris that are stable in time, meaning that we can track them. Fig. 7 shows the position of the features in one frame of the video. A number of the features found are caused by the eyelashes, since they appear to be a similar intensity to the iris. We could naturally remove these by explicitly finding the eyelids and excluding features near the eyelids, but in this case, they should not cause a problem, since there are so many other features present. For this video, the monkey was stationary, and since there was no torsional movement of the eyes, we have omitted the corresponding torsion plot.
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