Research on Exact Location Algorithm of Pupil Center Based on Ellipse Fitting
10.3969/j.issn.1671-7104.2017.03.004
- VernacularTitle:基于椭圆拟合的瞳孔中心精确定位算法研究
- Author:
Luo YU
1
;
Hongying LIU
;
Xitian PI
;
Weiming CHEN
;
Shuai XU
;
Xu YAN
Author Information
1. 重庆大学生物医学工程学院
- Keywords:
eye-tracking;
pupil center;
location algorithm;
ellipse fitting
- From:
Chinese Journal of Medical Instrumentation
2017;41(3):170-174
- CountryChina
- Language:Chinese
-
Abstract:
In order to realize the requirement of precise eye tracking in clinical, a pupil center location algorithm based on the least square method is proposed. First, the eye image was captured by the camera under the infrared light, and then the two-valued image was obtained after preprocessing. Use the number of pixels that form the outline which was Extracting from the two-valued image to carry out the rough filtration of the pupil. The ellipse curve was fitting by the randomly select 6 pixels on the filtered contours, and then calculated the variance of distance between the center and the edge of the ellipse. The ellipse center is ellipse center, where the variance of the distance is Minimum. The algorithm has advantage of accurate identification the pupil center when there is white spot interference and squint.Experiments show that the pupil center can be located quickly and real-timely by this algorithm.
