一种提取微血管边缘曲线角点策略

STRATEGY OF CORNER POINTS EXTRACTION FOR MICRO VESSEL CONTOUR

通过深入讨论用链码表示的非常不规则的曲线（如生物医学对象的边缘曲线）的形态，本文提出一种所谓低阈值双窗二次角点选择角点提取策略。第一步，用两个不同的窗口尺寸计算曲线上各点的链码曲率值，然后用相对低的曲率阈值选取候选角点；第二步，利用候选角点的聚类特征和链码曲率极值及微血管边缘曲线的几何特征删除多余角点，确定真实角点。微血管边缘曲线的角点提取实验结果表明效果良好。

A strategy of corner point extraction for non rigid body contour was presented in this paper.After studying deeply the forms of the contour of non rigid biomedical objects such as the contour of micro vessels,an algorithm of corner point extraction of curves expressed by chain code was provided,i.e.the so called twice determining corner point set with a low threshold and two window sizes.Firstly,calculated curvature of all points at a curve with two different window sizes according to our deriving formulations,and then choose all the candidates of corner points.Secondly,determined the candidates with maximum curvature for every cluster according to cluster analysis,and then deleted unsuitable cluster corner points under the condition of the neighbor corner point distance constrain.The results showed that the strategy was useful and helpful for micro vessel contour extraction.It was meaningful forcorner point extraction of a soft bodys contour.