Automatic Seamline Determination for Urban Image Mosaicking Based on Road Probability Map from the D-LinkNet Neural Network.

Shenggu Yuan,Xin Li,Hongyue Cai,Ke Yang

doi:10.3390/s20071832

Abstract

Image mosaicking which is a process of constructing multiple orthoimages into a single seamless composite orthoimage, is one of the key steps for the production of large-scale digital orthophoto maps (DOM). Seamline determination is one of the most difficult technologies in the automatic mosaicking of orthoimages. The seamlines that follow the centerlines of roads where no significant differences exist are beneficial to improve the quality of image mosaicking. Based on this idea, this paper proposes a novel method of seamline determination based on road probability map from the D-LinkNet neural network for urban image mosaicking. This method optimizes the seamlines at both the semantic and pixel level as follows. First, the road probability map is obtained with the D-LinkNet neural network and related post processing. Second, the preferred road areas (PRAs) are determined by binarizing the road probability map of the overlapping area in the left and right image. The PRAs are the priority areas in which the seamlines cross. Finally, the final seamlines are determined by Dijkstra’s shortest path algorithm implemented with binary min-heap at the pixel level. The experimental results of three group data sets show the advantages of the proposed method. Compared with two previous methods, the seamlines obtained by the proposed method pass through the less obvious objects and mainly follow the roads. In terms of the computational efficiency, the proposed method also has a high efficiency.

Highlights

Orthoimages have increasingly become a popular visualization product and planning instrument for integrating the rich information content of images with the geometric properties of maps and can be combined with additional information from geographic information systems (GIS) to create an orthoimage map [1]
Our work focuses on automatic seamline determination for urban image mosaicking
We propose a novel method of seamline determination based on a road probability map which is extracted by the D-LinkNet neural network for urban image mosaicking

Summary

Introduction

Orthoimages have increasingly become a popular visualization product and planning instrument for integrating the rich information content of images with the geometric properties of maps (ground projection) and can be combined with additional information from geographic information systems (GIS) to create an orthoimage map [1]. With the development of technology, the orthoimage spatial resolution becomes higher, and the coverage area of an individual orthoimage is typically very small image mosaicking is a necessary process of constructing multiple images into a large-scale and single seamless composite image. This process has been applied in a wide variety of applications such as environmental monitoring, agricultural monitoring, and disaster management [2,3]. Objects not contained in the DTM cannot be orthorectified correctly Those objects would appear at different locations in the overlapping area and cause visual discontinuities in image mosaicking.

Methods

Results

Conclusion