Dasymetric Mapping Using UAV High Resolution 3D Data Within Urban Areas

Abstract

Multi-temporal analysis of census small-area microdata is hampered by the fact that census tract shapes do not often coincide between census exercises. Dasymetric mapping techniques provide a workaround that is nonetheless highly dependent on the quality of ancillary data. The objectives of this work are to: (1) Compare the use of three spatial techniques for the estimation of population according to census tracts: Areal interpolation and dasymetric mapping using control data—building block area (2D) and volume (3D); (2) demonstrate the potential of unmanned aerial vehicle (UAV) technology for the acquisition of control data; (3) perform a sensitivity analysis using Monte Carlo simulations showing the effect of changes in building block volume (3D information) in population estimates. The control data were extracted by a (semi)-automatic solution—3DEBP (3D extraction building parameters) developed using free open source software (FOSS) tools. The results highlight the relevance of 3D for the dasymetric mapping exercise, especially if the variations in height between building blocks are significant. Using low-cost UAV backed systems with a FOSS-only computing framework also proved to be a competent solution with a large scope of potential applications.

Identification and Geographic Distribution of Accommodation and Catering Centers

“…However, with the rapid development of Internet technology, several types of geospatial data are continuously enriched, such as mobile phone signaling data, Global Positioning System (GPS) trajectory, and point of interest (POI) data. [18,19], providing high-resolution data support for evaluating the spatial distribution patterns of discrete geographical entities. For example, based on POI data and using catering POI data, Lan and Yu [20] analyzed the composition types and temporal and spatial evolution characteristics of restaurants within the Fifth Ring Road in Beijing at three different scales: the macro scale, the meso scale, and the micro scale.…”

Editorial for Special Issue: “Remote Sensing for Urban Morphology”

“…Dasymetric mapping is an established procedure that has been used for areal interpolation of remotely sensed data using an ancillary variable (usually demographic information from a population census). In the third paper, Rebelo et al [4] apply dasymetric mapping to three-dimensional high spatial resolution data at 6-cm resolution from an unmanned aerial vehicle (UAV). They conclude that the extraction of accurate building volumes depend on the location of sample points from the UAV along eaves of roofs.…”