Documentation of heritage buildings using close‐range UAV images: dense matching issues, comparison and case studies

Abstract

Three-dimensional (3D) documentation of heritage buildings has long employed both image-based and range-based techniques. Unmanned aerial vehicles (UAVs) provide a particular advantage for image-based techniques in acquiring aerial views, which are difficult to attain using classical terrestrial-based methods. The technological development of optical sensors and dense matching algorithms also complement existing photogrammetric workflows for the documentation of heritage objects. In this paper, fundamental concepts in photogrammetry and 3D reconstruction based on structure from motion (SfM) will be briefly reviewed. Two case studies were performed using two types of UAVs, one being a state-of-the-art platform dedicated to obtaining close-range images. Comparisons with laser scanning data were performed and several issues regarding the aerial triangulation and dense matching results were assessed. The results show that although the dense matching of these UAV images may generate centimetre-level precision, a further increase in precision is often hampered by the quality of the onboard sensor.

Investigations on the Bundle Adjustment Results From SFM-Based Software for Mapping Purposes

“…These improvements to the photogrammetric workflow have given rise to various software solutions providing relatively accurate results with increasingly less and less user involvement. The growing trend of the use of SfMbased software in topographic mapping is also aided by the democratisation of UAVs (Murtiyoso and Grussenmeyer, 2017). That being said, in terms of topographic survey, mapping agencies such as BIG still prefers to employ photogrammetryfocused software (e.g.…”

“…For example, comparisons has been done in terms of dense point cloud (Murtiyoso and Grussenmeyer, 2017;Sapirstein, 2016), Digital Surface Models (DSM) (Remondino et al, 2013;Runkel et al, 2017), bundle adjustment results (Murtiyoso et al, 2018), or orthophoto generation (Chiabrando et al, 2015). This paper will focus on bundle adjustment or aerotriangulation assessment, being one of the most important factors influencing the final precision of topographic mapping.…”

“…The advent of UAV (Unmanned Aerial Vehicles) technology and developments in the domain of computer vision has largely facilitated the traditional photogrammetric workflow (Murtiyoso and Grussenmeyer, 2017). Several traditionally manual photogrammetric tasks such as tie point marking and orthophoto production have been automated to a degree where a simple button may be sufficient to perform these tasks (Remondino et al, 2011).…”

Debitage and Drones: Classifying and Characterising Neolithic Stone Tool Production in the Shetland Islands Using High Resolution Unmanned Aerial Vehicle Imagery

“…Both projects illustrated the utility of UAV platforms in remote and difficult-to-reach areas where other data sources or techniques were not available. UAV platforms have also been used to monitor looting [23] and to record extant monuments [24]. The flexibility and affordability of UAV platforms should be set alongside their limitations.…”

Open Source and Independent Methods for Bundle Adjustment Assessment in Close-Range UAV Photogrammetry

“…In that regard, the method of close-range photogrammetry has been used many times to capture 3D information from 2D images (e.g., shape, position and size) [1]. Close-range photogrammetry has seen various applications, such as the modeling of facades [2], buildings [3,4], monuments [5,6], etc. Developments in imaging sensor technology have made this method a great alternative or complement to terrestrial laser scanners [7][8][9].…”