瞳孔和眼角的梯度特征重构快速定位算法

Fast Eye Center and Corner Location by Gradient Feature Reconstruction

为了快速提取人脸图像局部特征点,提出一种基于梯度特征重构的瞳孔和眼角快速定位算法.通过分析人眼图像发现眼部区域的梯度特征以瞳孔为中心呈辐射状分布,根据梯度方向与辐射中心的关系提出了有限扩散的梯度能量函数;然后基于有限扩散的梯度能量函数进行瞳孔和眼角的检测与定位;之后,根据瞳孔和眼角几何约束关系进一步对定位结果进行合理化的调整,确保检测结果的稳定性.该算法只利用梯度信息,对光照线性变化不敏感.在Muct数据库和Bio ID数据库以及普通摄像头上进行了测试的结果表明,该算法检测精度高、计算复杂度低、检测速度快,可以满足实时应用.

In order to quickly extract the facial feature points, we propose a fast eye center and corner local-ization algorithm which is based on the reconstructed gradient feature. Studies have shown that gradient feature of human eyes is radiating distribution centered on pupil. Based on that, the algorithm proposed in this paper compute the center to detect the location of the pupil and the eye corners. Then necessary adjust-ments with respect to the relative location of both pupil and eye corner is employed to eliminate the gross error. Only the original gradient information is used which is invariant to affine lighting changes. The images from both Muct and BioID database as well as low-resolution web camera are used to test the proposed al-gorithm. The experimental result demonstrate that the proposed algorithm has high detection precision with low computational cost, which can meet the demand of real-time applications.