Results 61 to 70 of about 10,286,824 (193)

Assessing the Accuracy of Digital Surface Models Derived from Optical Imagery Acquired with Unmanned Aerial Systems

Drones, 2019
Small unmanned aerial systems (UASs) equipped with an optical camera are a cost-effective strategy for topographic surveys. These low-cost UASs can provide useful information for three-dimensional (3D) reconstruction even if they are equipped with a low ...
Salvatore Manfreda, Petr Dvorak, Jana Mullerova, Sorin Herban, Pietro Vuono, José Juan Arranz Justel, Matthew Perks   +6 more
doaj   +1 more source

Camera Calibration for Coastal Monitoring Using Available Snapshot Images

Remote Sensing, 2020
Joint intrinsic and extrinsic calibration from a single snapshot is a common requirement in coastal monitoring practice. This work analyzes the influence of different aspects, such as the distribution of Ground Control Points (GCPs) or the image ...
Gonzalo Simarro, Daniel Calvete, Paola Souto, Jorge Guillén   +3 more
doaj   +1 more source

Updating Orthophotos around Gas Pipelines based on "Cloud Control" Photogrammetry [PDF]

ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
As a clean energy source, natural gas is widely used and primarily transported through long-distance pipelines. Regular maintenance and inspection of long-distance gas pipelines are crucial tasks.
L. Qin, Y. Liu, X. Zhao, Y. Duan, Y. Duan   +4 more
doaj   +1 more source

HYBRID GEOMETRIC CALIBRATION METHOD FOR MULTI-PLATFORM SPACEBORNE SAR IMAGE WITH SPARSE GCPS [PDF]

The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2018
Geometric calibration is able to provide high-accuracy geometric coordinates of spaceborne SAR image through accurate geometric parameters in the Range-Doppler model by ground control points (GCPs).
G. Lv, G. Lv, X. Tang, B. Ai, T. Li, Q. Chen   +5 more
doaj   +1 more source

Determining the Optimum Number of Ground Control Points for Obtaining High Precision Results Based on UAS Images

, 2018
Ground control points (GCPs) are used in the process of indirectly georeferencing Unmanned Aerial Systems (UAS) images. A minimum of three ground control points (GCPs) is required but increasing the number of GCPs will lead to higher accuracy of the ...
Florian Statescu, Ana-Ioana Breaban, Valeria-Ersilia Oniga   +2 more
core   +1 more source

Measurement of surface velocity in open channels using a lightweight remotely piloted aircraft system

Geomatics, Natural Hazards & Risk, 2017
In this paper, a low-cost remotely piloted aircraft system (RPAS) technique is proposed for measurement of the surface velocity in rivers or channels with low surface velocity and small discharge.
M. Bolognesi, G. Farina, S. Alvisi, M. Franchini, A. Pellegrinelli, P. Russo   +5 more
doaj   +1 more source

A Region Growing controlled by Edge Map technique (RGCE) for Automatic Registration of Satellite Images [PDF]

Journal of the ACS Advances in Computer Science, 2019
Image registration is a basic and troublesome assignment where managingremotely sensed satellite images. The registration of different platform images has turnedinto a critical issue with an expanding number of images gathered each day from ...
doaj   +1 more source

Automating Ground Control Point Detection in Drone Imagery: From Computer Vision to Deep Learning

Remote Sensing
Drone-based photogrammetry typically requires the task of georeferencing aerial images by detecting the center of Ground Control Points (GCPs) placed in the field. Since this is a very labor-intensive task, it could benefit greatly from automation.
Gonzalo Muradás Odriozola, Klaas Pauly, Samuel Oswald, Dries Raymaekers   +3 more
doaj   +1 more source

Accuracy assessment of RTK/PPK UAV-photogrammetry projects using differential corrections from multiple GNSS fixed base stations

Geocarto International, 2023
Unmanned aerial vehicles (UAVs) equipped with global navigation satellite system-real-time kinematic (GNSS RTK) receivers allow direct georeferencing of the photogrammetric project without using ground control points (GCPs).
Patricio Martínez-Carricondo, Francisco Agüera-Vega, Fernando Carvajal-Ramírez   +2 more
doaj   +1 more source

Accuracy Analysis of a Dam Model from Drone Surveys

Sensors, 2017
This paper investigates the accuracy of models obtained by drone surveys. To this end, this work analyzes how the placement of ground control points (GCPs) used to georeference the dense point cloud of a dam affects the resulting three-dimensional (3D ...
Elena Ridolfi, Giulia Buffi, Sara Venturi, Piergiorgio Manciola   +3 more
doaj   +1 more source