基于改进虚拟格网的机载LiDAR数据的形态学滤波

发布时间：2018-06-28 21:33

本文选题：激光测距 + 虚拟格网　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：机载LiDAR(Light Detection and Ranging，激光探测与测量)技术是一种崭新的遥感技术。机载LiDAR融合了激光测距技术手段和测量方法，它能够主动、快速、精确获取地面和目标的三维空间信息，给人们带来了新型的观测途径。如何有效的把海量点云数据规则或半规则的组织起来，对后续的数字产品生产和应用都起到关键作用。数据滤波DEM（Digital Elevation Model，数字高程模型)生产技术是已经成为LiDAR数据处理的最基础工作。本文围绕数据滤波采用改进hash链表的虚拟格网组织方式组织机载LiDAR点云数据，并在此基础上改进形态学滤波方法。主要研究工作和创新成果如下： 1.系统阐述了机载LiDAR的历史及背景，总结了国内外的研究现状，详细分析了数据处理的难点，为后续点云数据的组织和滤波算法设计提供理论依据和数据支持。 2.介绍机载LiDAR系统的组成结构，各个部件获得数据，经最终解算得到LiDAR数据。介绍机载LiDAR数据的处理流程，并结合LiDAR数据常用处理软件TerraSolid，对每步数据处理操作和用途做了详细的介绍。 3.总结机载LiDAR点云数据的常用组织方式，针对数据量大、数据查找频繁地操作特点，提出一种简单的基于hash链表的改进的虚拟格网组织方式，该组织方式采用hash链表原理，结合虚拟格网和四叉树优点，且具有简单、快速的优势。 4.改进了基于虚拟格网数据组织结构的形态学滤波算法。数组组织采用基于虚拟格网的数据组织方式，，避免对原始数据进行重采样损失精度。利用最大建筑物的之间作为最大窗口的阈值条件，对前后两次形态学开运算的结果进行判断，提高滤波的准确度，避免简单的阈值和单一的窗口对地形数据的损失。通过实验分析证明，算法具有很强的适应性、准确性，在城区等相对比较平坦的地形具有良好的滤波效果。
[Abstract]:Airborne LiDAR (Light Detection and angling) technology is a new remote sensing technology. Airborne LiDAR combines laser ranging technology with measurement method. It can acquire 3D spatial information of ground and target actively, quickly and accurately, which brings people a new way of observation. How to effectively organize the rules or semi-rules of massive point cloud data plays a key role in the subsequent production and application of digital products. Data filtering Dem (Digital elevation Model) production technology has become the most basic work of LiDAR data processing. In this paper, the point cloud data of airborne LiDAR are organized by virtual grid with improved hash linked list around data filtering, and the morphological filtering method is improved. The main research and innovative results are as follows: 1. In this paper, the history and background of airborne LiDAR are described systematically, the research status at home and abroad is summarized, and the difficulties of data processing are analyzed in detail, which provides theoretical basis and data support for the organization of point cloud data and the design of filtering algorithm. 2. The structure of the airborne LiDAR system is introduced. The data of each component are obtained and the LiDAR data are obtained by the final solution. This paper introduces the processing flow of airborne LiDAR data and introduces in detail the operation and usage of each step data processing with the commonly used software TerraSolid. This paper summarizes the common organization methods of airborne LiDAR point cloud data. According to the characteristics of large amount of data and frequent operation of data lookup, a simple and improved virtual grid organization method based on hash linked list is proposed, which adopts the principle of hash linked list. Combine the advantages of virtual grid and quadtree, and have the advantages of simple and fast. 4. The morphological filtering algorithm based on virtual grid data organization structure is improved. Array organization is based on virtual grid to avoid resampling and losing precision of raw data. By using the threshold condition between the maximum buildings as the maximum window, the results of the two morphological operations before and after are judged to improve the accuracy of filtering and to avoid the loss of topographic data caused by simple threshold and single window. The experimental results show that the algorithm has strong adaptability, accuracy and good filtering effect in relatively flat terrain such as urban area.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP79;TN713

【参考文献】