Eyelid location using Asymmetry Canny Operator

According to the physiological structure of human eye, the low-pass filter is used to do convolution with the iris image, which is to reduce the interference of the high-frequency information, such as eyelid. And then, Asymmetry Canny Operator is used to do horizontal and vertical edge diction, which is to reduce the interference of eyelash, and strengthen the edge of eyelid. The initial eyelid location was finished by curve fitting to the eyelid that obtained through edge diction. Finally, in the light of individual differences of the eyelid edge, which has the character of single-layer and double-layer, so it constructs parabola edge operator and executes the second search for real eyelid edge on the basis of the acquired eyelid edge in the first detection. The experiment shows that the idea of the algorithm is concise and universal, and the location accurate rate is high. So it is a novel and effective eyelid location algorithm.