{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T01:33:09Z","timestamp":1776130389531,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2018,3,14]],"date-time":"2018-03-14T00:00:00Z","timestamp":1520985600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJGI"],"abstract":"<jats:p>Unmanned Aerial Vehicle (UAV) imagery allows for a new way of obtaining geographic information. In this work, a Geographical Information System (GIS) open source application was developed in QGIS software that estimates several parameters and metrics on tree crown through image analysis techniques (image segmentation and image classification) and fractal analysis. The metrics that have been estimated were: area, perimeter, number of trees, distance between trees, and a missing tree check. This methodology was tested on three different plantations: olive, eucalyptus, and vineyard. The application developed is free, open source and takes advantage of QGIS integration with external software. Several tools available from Orfeo Toolbox and Geographic Resources Analysis Support System (GRASS) GIS were employed to generate a classified raster image which allows calculating the metrics referred before. The application was developed in the Python 2.7 language. Also, some functions, modules, and classes from the QGIS Application Programming Interface (API) and PyQt4 API were used. This new plugin is a valuable tool, which allowed for automatizing several parameters and metrics on tree crown using GIS analysis tools, while considering data acquired by UAV.<\/jats:p>","DOI":"10.3390\/ijgi7030109","type":"journal-article","created":{"date-parts":[[2018,3,15]],"date-time":"2018-03-15T05:06:43Z","timestamp":1521090403000},"page":"109","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Development of a QGIS Plugin to Obtain Parameters and Elements of Plantation Trees and Vineyards with Aerial Photographs"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7537-6606","authenticated-orcid":false,"given":"Lia","family":"Duarte","sequence":"first","affiliation":[{"name":"Department of Geosciences, Environment and Land Planning, Faculty of Sciences, University of Porto, Porto 4169-007, Portugal"},{"name":"Earth Sciences Institute (ICT), Faculty of Sciences, University of Porto, Porto 4169-007, Portugal"}]},{"given":"Pedro","family":"Silva","sequence":"additional","affiliation":[{"name":"Department of Geosciences, Environment and Land Planning, Faculty of Sciences, University of Porto, Porto 4169-007, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0019-6862","authenticated-orcid":false,"given":"Ana","family":"Teodoro","sequence":"additional","affiliation":[{"name":"Department of Geosciences, Environment and Land Planning, Faculty of Sciences, University of Porto, Porto 4169-007, Portugal"},{"name":"Earth Sciences Institute (ICT), Faculty of Sciences, University of Porto, Porto 4169-007, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Santoro, F., Tarantino, E., Figorito, B., Gualano, S., and D\u2019Onghia, A.M. 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