具有方向性、变尺度的过零交叉特征检测算子

A Directional and Scale-Variable Zero-Crossing Edge Detector

根据过零交叉的视觉机理，提出了一种具有方向选择性和变尺度的特征检测算子，并以Ｂ样条形式给出了其小尺度下的离散化图象处理形式。该算子的提出与实现，克服了以前的方向性模板的视觉解释的不完善现象，使得过零交叉理论与人眼观察的特征方向性选择得到了完整的统一。该算子在水平方向与垂直方向的叠加形式能较好地解释人眼视觉系统为何对水平方向和垂直方向的特征反应较斜向方向的特征反应更为敏感这一生理现象，并由此对人眼视觉机理作出了一种新的、合理的解释，从而进一步完善了传统的过零交叉视觉理论。

ased on the zero-crossing theory, a new kind of edge detector with orientation selectivity and variable scale is presented, and its discrete B spline form under a small scale is also given. The presentation and realization of this operator eliminates imperfection of the directional mask in a vision model and it integrates the orientation selectivity of human visiual system (HVS) with the zero-crossing theory. The combination of its vertical form with its horizontal form gives a better explanation why the HVS is more sensible to the excitation of the horizontal and vertical than that of the diagonal.So it not only gives a rational new explanation of the HVS,but also makes the traditional zero-crossing theory more perfect.