{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T13:53:43Z","timestamp":1772286823202,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T00:00:00Z","timestamp":1614211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/00048\/2020"],"award-info":[{"award-number":["UIDB\/00048\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Measuring biometric tree characteristics to estimate the volume of wood in a forest area is a time consuming task. It is usually performed by a team of two or more people, who measure the diameter and height of several trees in sampling plots. The results are then extrapolated for the forest stand. The present paper describes a method which facilitates estimating tree biometric parameters using computational techniques. A camera takes two pictures of each sample tree, with an especially designed target placed close to the tree, to facilitate image processing and camera calibration steps. Taking advantage of the trees\u2019 natural shape and assuming a symmetric stem, the diameter and height of the tree stems are estimated from the images and the volumes of the tree stems are calculated. Experimental trials show promising results, exhibiting errors similar to the traditional methods used currently, in the range of 10%, showing that the method is suitable for forest inventory.<\/jats:p>","DOI":"10.3390\/sym13030374","type":"journal-article","created":{"date-parts":[[2021,2,26]],"date-time":"2021-02-26T06:47:20Z","timestamp":1614322040000},"page":"374","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Non-Destructive Fast Estimation of Tree Stem Height and Volume Using Image Processing"],"prefix":"10.3390","volume":"13","author":[{"given":"Jo\u00e3o","family":"Coelho","sequence":"first","affiliation":[{"name":"ISR, Departamento de Engenharia Electrot\u00e9cnica e de Computadores da UC, University of Coimbra, 3004-531 Coimbra, Portugal"},{"name":"Instituto Superior de Engenharia de Coimbra, Polytechnic of Coimbra, 3004-531 Coimbra, Portugal"}]},{"given":"Beatriz","family":"Fidalgo","sequence":"additional","affiliation":[{"name":"School of Agriculture of Coimbra, Polytechnic of Coimbra, 3004-531 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3240-7564","authenticated-orcid":false,"given":"Manuel M.","family":"Cris\u00f3stomo","sequence":"additional","affiliation":[{"name":"ISR, Departamento de Engenharia Electrot\u00e9cnica e de Computadores da UC, University of Coimbra, 3004-531 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0808-1928","authenticated-orcid":false,"given":"Ra\u00fal","family":"Salas-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"School of Agriculture of Coimbra, Polytechnic of Coimbra, 3004-531 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3780-2405","authenticated-orcid":false,"given":"A. Paulo","family":"Coimbra","sequence":"additional","affiliation":[{"name":"ISR, Departamento de Engenharia Electrot\u00e9cnica e de Computadores da UC, University of Coimbra, 3004-531 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4313-7966","authenticated-orcid":false,"given":"Mateus","family":"Mendes","sequence":"additional","affiliation":[{"name":"ISR, Departamento de Engenharia Electrot\u00e9cnica e de Computadores da UC, University of Coimbra, 3004-531 Coimbra, Portugal"},{"name":"Instituto Superior de Engenharia de Coimbra, Polytechnic of Coimbra, 3004-531 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1080\/02827581.2017.1416666","article-title":"Remote sensing and forest inventories in Nordic countries\u2014Road map for the future","volume":"33","author":"Kangas","year":"2018","journal-title":"Scand. J. For. 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