1. A method for determining an estimated pupil region of an eye of a user, the method comprising: receiving an image of the eye of the user, the image comprising a plurality of pixels; generating a rough pupil region using at least a subset of the plurality of pixels; extracting from the rough pupil region a plurality of pupil boundary point candidate pixels; for each of the pupil boundary point candidate pixels, weighting the pupil boundary point candidate pixel based on color values of at least two neighbor pixels of the pupil boundary point candidate pixel to generate weighted pupil boundary point candidates; and fitting a parametric curve to the weighted pupil boundary point candidates to determine the estimated pupil region of the eye of the user.