结合边缘信息优化LSC和改进A^(*)算法的正射影像图镶嵌线提取  

Mosaic line extraction of orthophoto image based on optimized LSC and improved A^(*) algorithm combined with edge information

作　　者：刘然 刘岩 吴卓航 李冬雪 马强 LIU Ran;LIU Yan;WU Zhuohang;LI Dongxue;MA Qiang(Economic Research Institute of State Grid Liaoning Electric Power Supply Co.,LTD.,Shenyang 110065)

机构地区：[1]国网辽宁省电力有限公司经济技术研究院,沈阳110065

出　　处：《南京信息工程大学学报（自然科学版）》2023年第4期403-411,共9页Journal of Nanjing University of Information Science & Technology（Natural Science Edition）

基　　金：国网辽宁省电力有限公司经济技术研究院科技项目(SGLNJY00SJJS2100060)。

摘　　要：为避免正射影像图在镶嵌时镶嵌线穿过视觉显著地物,损害影像中地物的完整性,本文提出一种结合边缘信息优化LSC(线性谱聚类)和改进A^(*)算法的正射影像图镶嵌线提取方法.首先,将经典LSC的超像素分割理论引入正射影像图镶嵌线提取算法中,并提出边缘强度因子用以优化经典线性谱聚类,有效利用正射影像图中的光谱信息和边缘信息;然后,将优化后的LSC分别应用于两幅正射影像的重叠数据集,得到各类地物的边界特征图,并通过数学形态学法去除边界特征图中的边缘不整齐现象和孤立噪点;最后,改进传统A^(*)算法,由曼哈顿距离函数替代原有基于欧式距离测度的启发函数,提升A^(*)算法进行最短路径搜索的效率,在边界特征图中快速搜索出最短路径得到最优镶嵌线.利用真实无人机航拍正射影像图将本文方法与相关方法进行对比分析,实验结果表明本文所提方法可高效、高质量地提取到影像镶嵌线,有效绕过视觉显著地物,减少镶嵌线穿过地物的像元点数,满足实际正射影像图制作的应用需求.In order to prevent the mosaic line from passing through the visually significant features of orthophoto map thus damaging its integrity,a mosaic line extraction approach for orthophoto images is proposed,which combines edge information with optimized Linear Spectral Clustering(LSC)and improved A^(*)algorithm.First,the super-pixel segmentation theory of LSC is introduced for the mosaic line extraction,of which the classical LSC is optimized by edge intensity factor to effectively use the spectral information and edge information in orthophoto images.Second,the improved LSC is applied to the overlapping areas of two orthophoto images to obtain the boundary feature maps with various ground objects,and then the edge irregularity and isolated noise in the boundary feature maps are removed by mathematical morphology.Finally,the A^(*)algorithm is improved by replacing the original heuristic function based on Euclidean distance measure with Manhattan distance function,and then used to search the shortest path in the boundary map to quickly obtain the optimal image mosaic line.This approach is compared with related methods by using aerial orthophoto image taken by a UAV.The results show that the proposed approach can extract mosaic lines efficiently and with high quality,during which it effectively bypasses the visual salient features and meets the application requirements of orthophoto mapping.

关 键 词：线性谱聚类 边界特征图 A^(*)算法 正射影像 镶嵌线提取 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]