一种基于逻辑判断的山谷型边界检测方法

Valley Type Edge Detection Method Based on Logic Judgement

针对特定环境目标图象的分割 ,提出了一种基于逻辑判断的非监督边界检测方法 ,该方法可直接从原始图象中提取边界 ,而不需要进行边界强度计算和阈值分类 ,其算法简单 ,且具有噪声滤波功能 ,故适合于山谷型边界检测 ,通过堆积类球形颗粒轮廓的提取实验证明 。

In this paper, firstly the distribution characteristic of accumulate granule on the image gray space is analyzed under the different angles and distributions of light ray, the foundation is provided for abstracting granule contour information. A non supervisory roof edge detection method is proposed based on a logic judgement, which includes four steps:(1) The analysis window consisting of 3×3 sub windows is assumed, where each sub window consist of l×l pixels, the size of sub window is related to the size of objects. (2) The gray average value of 3×3 sub windows is calculated. (3) The gray average values of 3×3 sub windows is compared respectively along four directions, if the gray average value of center sub window is smaller than one of other two sub windows in some direction, the center or some near center pixel in the sub window is labeled as the candidate of edge pixel. (4) Scanning original image get the edge bit map by the analysis window. (5) The false edge pixels in the bit map can be removed by the proposed false edge filtering method. This method need not to the conventional procedure of abstracting edge pixels through calculating edge intensity and then thresolding edge intensity, is suited to the roof edge detection. The experiment results of the granule contour abstraction in accumulate global granule image proved that the method is effective.