亚像素级光刀中心提取方法研究

Research on Extraction Method of Sub-Pixel Laser-Knife Centre

针对三维激光扫描中快速精确提取光刀中心困难的问题,提出了一种新的亚像素级光刀中心提取方法。首先对光刀图像进行包括灰度变换、分割以及基于数学形态学处理的干扰去除三步骤在内的预处理;然后重点对传统的重心法进行改进,利用形态学方法对二值化后的光刀进行细化和去支处理得到其骨架,法线方向可近似为垂直于其所在骨架相邻两点连线的方向;最后利用重心法沿各点法线方向求解得到了亚像素级光刀中心。实验表明该方法具有处理速度快、精度高的特点。

Quick and accurate extracting of the laser-knife centre is difficult in three-dimensional laser scan- ning. A new sub-pixel laser-knife center extraction method is proposed. Firstly, the laser-knife image is pre-pro- cessed by means of gray-scale transformation, segmentation and interference removing based on morphology. Then, an improved gravity method is proposed to detect sub-pixel laser-knife center. Skeleton of laser-knife is obtained by thinning and removing fringe based on morphological methods. The normal direction can be approx- imated as the direction which is vertical of the line between two adjacent points. Finally, the sub-pixel laser- knife center is extracted along the normal direction of every point by using gravity method. Experimental results confirm that the proposed method has good performance on accuracy and speed.