相位编组方法提取直线

相位编组方法的提出，是针对大多数直线抽取方法的两个主要弱点：１）利用灰度变化的幅度，作为局部边缘重要性的主要度量，受噪声影响较大；２）对边缘特征作局部决策前，缺乏对图像结构的全局理解。该方法有效地解决了以往方法中关于边缘检测算子尺寸方面的难题，可以从复杂的图像中抽取出低对比度的直线，并能获得不同类型的边缘图。

Lines Extraction with Phase-grouping Method

This paper expatiates on the approach to extraction of straight lines, which appears to be more effective than the existed techniques for two key reasons: (1) The gradient orientation (rather than gradient magnitude) is used as the initial organizing criterion prior to the extraction of straight lines. (2) The global context of the intensity variations associated with a straight line is determined prior to any local decisions about the participating edge elements, and so we can find the straight lines in reasonably complex images. particularly those lines that are long but not necessarily of high contrast.