标题: | 利用二次曲线近似法来计算二阶段霍夫转换来侦测数位影像中的直线和圆 Evaluation of the Two-Stages Hough Transform to Detect Lines and Circles in Digital Images by Using Quadratic Polynomial Fitting |
作者: | 纪富中 Fu-Chung Chi 林升甫 Sheng-Fuu Lin 电控工程研究所 |
关键字: | 2 阶段霍夫转换;圆形侦测;直线侦测;CAD应用;二次曲线近似法;21HT;Circle Detection;Lines Detection;CAD Application;Quadratic Polynomial Fitting |
公开日期: | 2001 |
摘要: | 本论文提出一种新的二阶段霍夫转换(two-stages Hough Transform)来侦测影像中的直线和圆。此种霍夫转换最主要的特色是利用二次曲线叠代的方式先算出影像中特征点的法线向量,进而把n维参数空间分解成n-1维的参数空间。我们利用此种方法来侦测圆并且延伸此种方法来侦测直线。在复杂影像中,大多部分的情况是只有直线和曲线。利用曲线叠代的方式,不只可以计算出特征点的法线方向也可以计算出曲率。利用直线和曲线的曲率不同的特性,在二阶段的直线霍夫转换里,可以有效的压抑曲线不去进行投票,而只让直线进行投票。在实验中可以获得很好的结果。我们并且把这些技术应用在CAD和其他实际的图形中,发觉效果很好。 A new two-stages Hough transform for detecting lines and circles in digital image is proposed here. The main feature of the new two-stages Hough transform is to evaluate the normal direction of the feature point by using quadratic polynomial fitting and decompose n dimension parameter array into n-1 dimension parameter array. The method is extended to detect lines in the digital image. In complicated images, the most curves are straight lines and circles and arcs. By using quadratic polynomial fitting, the normal direction and the curvature would be computed. By using the property of the different curvature between the lines and arcs, the non-straight lines are suppressed not to vote and only let the straight lines to vote in the two-stages Hough transform with quadratic polynomial fitting. The approach would get good performance in the experiment. The technique would be applied in CAD image and real pattern to get good results. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#NT900591061 http://hdl.handle.net/11536/69431 |
显示于类别: | Thesis |