Volume II-5
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., II-5, 57-63, 2014
https://doi.org/10.5194/isprsannals-II-5-57-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., II-5, 57-63, 2014
https://doi.org/10.5194/isprsannals-II-5-57-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.

  28 May 2014

28 May 2014

True-orthophoto generation from UAV images: Implementation of a combined photogrammetric and computer vision approach

L. Barazzetti1, R. Brumana1, D. Oreni1, M. Previtali1, and F. Roncoroni2 L. Barazzetti et al.
  • 1Politecnico di Milano, Department of Architecture, Built Environment and Construction Engineering (ABC) Via Ponzio 31, 20133 Milano, Italy
  • 2Politecnico di Milano, Polo Territoriale di Lecco, Via Previati 1/c, 23900 Lecco, Italy

Keywords: Automation, Matching, True-Orthophoto, UAV

Abstract. This paper presents a photogrammetric methodology for true-orthophoto generation with images acquired from UAV platforms. The method is an automated multistep workflow made up of three main parts: (i) image orientation through feature-based matching and collinearity equations / bundle block adjustment, (ii) dense matching with correlation techniques able to manage multiple images, and true-orthophoto mapping for 3D model texturing. It allows automated data processing of sparse blocks of convergent images in order to obtain a final true-orthophoto where problems such as self-occlusions, ghost effects, and multiple texture assignments are taken into consideration.

The different algorithms are illustrated and discussed along with a real case study concerning the UAV flight over the Basilica di Santa Maria di Collemaggio in L'Aquila (Italy). The final result is a rigorous true-orthophoto used to inspect the roof of the Basilica, which was seriously damaged by the earthquake in 2009.