Automatic determination of seamlines for aerial image mosaicking based on vector roads alone
Automatic determination of seamlines for aerial image mosaicking based on vector roads alone
复制标题
DOI：
10.1016/j.isprsjprs.2012.11.002
复制
发表时间：
2013-02
影响因子：
12.7
通讯作者：
Youchuan Wan;Dongliang Wang;J. Xiao;Xudong Lai;Jingzhong Xu
中科院分区：
文献类型：
--
作者：
Youchuan Wan;Dongliang Wang;J. Xiao;Xudong Lai;Jingzhong Xu
图像拼接定义为两个或多个图像的配准，然后将其组合成单个图像。在正射影像的自动拼接中，最困难的步骤之一是确定在重叠区域中放置缝线的位置。基于数百万像素的图像，现有的缝线检测方法主要关注如何避免越过高于地面的建筑物，从而导致重叠图像出现视差。然而，矢量格式的各种数据，如手动和精确绘制的矢量道路，并没有被用来帮助选择缝线。本文提出了一种仅使用矢量道路生成拼接线的新方法，并描述了其在武汉市图像拼接拼接中自动生成拼接线的应用。一条代表性的缝线提取如下。首先，在划分出单个图像的边界后，提取相邻图像重叠区域的骨架；其次，将重叠区域的矢量道路与提取的骨架叠加，构建加权图G （V， E）。最后，利用Floyd-Warshall算法寻找从I到O的代价最低的路径，即相邻图像多边形的两个交点，其中代价最低的路径为缝线。这种基于矢量的方法通常比基于栅格的方法更有效。实验证明了该方法的优点，特别是在矢量道路网络可用的情况下。
Image mosaicking is defined as the registration of two or more images that are then combined into a single image. One of the most difficult steps in the automatic mosaicking of orthoimages is deciding where to place seamlines in overlapping regions. Based on millions of image pixels, existing seamline detection methods mainly focus on how to avoid crossing buildings that are higher than the ground, which results in parallax on the overlapping images. However, various data in vector format, such as vector roads plotted manually and precisely, have not been used to aid the selection of seamlines. This paper presents a novel approach using vector roads alone to generate seamlines, and describes its application to the automatic generation of seamlines for image mosaicking of the city of Wuhan, China. A representative seamline is extracted as follows. First, the skeleton of the overlapping region of adjacent images is extracted after the delineation of boundaries of individual images. Second, vector roads in the overlapping region are overlaid with the extracted skeleton to build a weighted graph G (V, E). Finally, the Floyd–Warshall algorithm is applied to find the lowest cost path from I to O, which refer to two intersections of adjacent image polygons, with the lowest-cost path being the seamline. This vector-based approach is typically more efficient than raster-based approaches. Experiments demonstrate the merits of the proposed approach especially when vector road networks are available.