A method for eyelid shape estimation, comprising: under control of a hardware processor: generating an eye-box over an eye in an eye image, wherein the eye-box has two vertical edges (124a1, 124a2), an upper edge (124b1) and a lower edge (124b2), wherein each of the vertical edges (124a1, 124a2) is tangent to a limbic boundary of the eye, wherein the upper edge (124b1) overlays a portion of an upper eyelid of the eye, and wherein the lower edge (124b2) overlays a portion of a lower eyelid of the eye; generating a plurality of radial lines extending from a center of the eye-box to the upper edge (124b1) or the lower edge (124b2); determining more than three candidate points on the plurality of radial lines intersecting a same eyelid detected, using an edge detector, wherein the candidate points comprise points with local maximum derivatives and with largest distance from the center of the eye-box , along the plurality of the radial lines ; determining a parabolic fit curve from the more than three candidate points or a subset of three candidate point of said more than three candidate points , wherein the parabolic fit curve is an estimation of an eyelid shape of the eye in the eye image; determining a score of the parabolic fit curve is above a threshold score, wherein determining the score of the parabolic fit curve is above the threshold score comprises determining a number of the more than three candidate points that intersect the parabolic fit curve or determining a number of the more than three candidate points that are within a threshold distance of the parabolic fit curve ; and determining that the parabolic fit curve is a preferred estimation of the eyelid shape of the eye in the eye image. generating an eye-box over an eye in an eye image, wherein the eye-box has two vertical edges (124a1, 124a2), an upper edge (124b1) and a lower edge (124b2), wherein each of the vertical edges (124a1, 124a2) is tangent to a limbic boundary of the eye, wherein the upper edge (124b1) overlays a portion of an upper eyelid of the eye, and wherein the lower edge (124b2) overlays a portion of a lower eyelid of the eye; generating a plurality of radial lines extending from a center of the eye-box to the upper edge (124b1) or the lower edge (124b2); determining more than three candidate points on the plurality of radial lines intersecting a same eyelid detected, using an edge detector, wherein the candidate points comprise points with local maximum derivatives and with largest distance from the center of the eye-box , along the plurality of the radial lines ; determining a parabolic fit curve from the more than three candidate points or a subset of three candidate point of said more than three candidate points , wherein the parabolic fit curve is an estimation of an eyelid shape of the eye in the eye image; determining a score of the parabolic fit curve is above a threshold score, wherein determining the score of the parabolic fit curve is above the threshold score comprises determining a number of the more than three candidate points that intersect the parabolic fit curve or determining a number of the more than three candidate points that are within a threshold distance of the parabolic fit curve ; and determining that the parabolic fit curve is a preferred estimation of the eyelid shape of the eye in the eye image. <EOS>