{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T23:37:55Z","timestamp":1776814675161,"version":"3.51.2"},"reference-count":73,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2022,8,22]],"date-time":"2022-08-22T00:00:00Z","timestamp":1661126400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The National Natural Science Foundation of China","award":["41871322"],"award-info":[{"award-number":["41871322"]}]},{"name":"The National Natural Science Foundation of China","award":["61971418"],"award-info":[{"award-number":["61971418"]}]},{"name":"The National Natural Science Foundation of China","award":["U2003109"],"award-info":[{"award-number":["U2003109"]}]},{"name":"The National Natural Science Foundation of China","award":["62171321"],"award-info":[{"award-number":["62171321"]}]},{"name":"The National Natural Science Foundation of China","award":["62071157"],"award-info":[{"award-number":["62071157"]}]},{"name":"The National Natural Science Foundation of China","award":["62162044"],"award-info":[{"award-number":["62162044"]}]},{"name":"The National Natural Science Foundation of China","award":["2022GY-253"],"award-info":[{"award-number":["2022GY-253"]}]},{"name":"The Shaanxi Province Key R&amp;D Program","award":["41871322"],"award-info":[{"award-number":["41871322"]}]},{"name":"The Shaanxi Province Key R&amp;D Program","award":["61971418"],"award-info":[{"award-number":["61971418"]}]},{"name":"The Shaanxi Province Key R&amp;D Program","award":["U2003109"],"award-info":[{"award-number":["U2003109"]}]},{"name":"The Shaanxi Province Key R&amp;D Program","award":["62171321"],"award-info":[{"award-number":["62171321"]}]},{"name":"The Shaanxi Province Key R&amp;D Program","award":["62071157"],"award-info":[{"award-number":["62071157"]}]},{"name":"The Shaanxi Province Key R&amp;D Program","award":["62162044"],"award-info":[{"award-number":["62162044"]}]},{"name":"The Shaanxi Province Key R&amp;D Program","award":["2022GY-253"],"award-info":[{"award-number":["2022GY-253"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Individual tree counting (ITC) is a popular topic in the remote sensing application field. The number and planting density of trees are significant for estimating the yield and for futher planing, etc. Although existing studies have already achieved great performance on tree detection with satellite imagery, the quality is often negatively affected by clouds and heavy fog, which limits the application of high-frequency inventory. Nowadays, with ultra high spatial resolution and convenient usage, Unmanned Aerial Vehicles (UAVs) have become promising tools for obtaining statistics from plantations. However, for large scale areas, a UAV cannot capture the whole region of interest in one photo session. In this paper, a real-time orthophoto mosaicing-based tree counting framework is proposed to detect trees using sequential aerial images, which is very effective for fast detection of large areas. Firstly, to guarantee the speed and accuracy, a multi-planar assumption constrained graph optimization algorithm is proposed to estimate the camera pose and generate orthophoto mosaicing simultaneously. Secondly, to avoid time-consuming box or mask annotations, a point supervised method is designed for tree counting task, which greatly speeds up the entire workflow. We demonstrate the effectiveness of our method by performing extensive experiments on oil-palm and acacia trees. To avoid the delay between data acquisition and processing, the proposed framework algorithm is embedded into the UAV for completing tree counting tasks, which also reduces the quantity of data transmission from the UAV system to the ground station. We evaluate the proposed pipeline using sequential UAV images captured in Indonesia. The proposed pipeline achieves an F1-score of 98.2% for acacia tree detection and 96.3% for oil-palm tree detection with online orthophoto mosaicing generation.<\/jats:p>","DOI":"10.3390\/rs14164113","type":"journal-article","created":{"date-parts":[[2022,8,22]],"date-time":"2022-08-22T23:49:56Z","timestamp":1661212196000},"page":"4113","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Fast Tree Detection and Counting on UAVs for Sequential Aerial Images with Generating Orthophoto Mosaicing"],"prefix":"10.3390","volume":"14","author":[{"given":"Pengcheng","family":"Han","sequence":"first","affiliation":[{"name":"School of Civilaviation, School of Aeronautics, Northwestern Polytechnical University, Xi\u2019an 710072, China"},{"name":"Xi\u2019an Vision Huitu Intelligent Technology Co., Ltd., Xi\u2019an 710000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cunbao","family":"Ma","sequence":"additional","affiliation":[{"name":"School of Civilaviation, School of Aeronautics, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jian","family":"Chen","sequence":"additional","affiliation":[{"name":"Energy and Power Engineering School, Xi\u2019an Jiaotong University, Xi\u2019an 710000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lin","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Civilaviation, School of Aeronautics, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9853-8313","authenticated-orcid":false,"given":"Shuhui","family":"Bu","sequence":"additional","affiliation":[{"name":"School of Civilaviation, School of Aeronautics, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4037-9900","authenticated-orcid":false,"given":"Shibiao","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Artificial Intelligence, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0834-1286","authenticated-orcid":false,"given":"Yong","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Civilaviation, School of Aeronautics, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chenhua","family":"Zhang","sequence":"additional","affiliation":[{"name":"Graduate School of Media and Governance, Keio University, Tokyo 108-8345, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tatsuya","family":"Hagino","sequence":"additional","affiliation":[{"name":"Graduate School of Media and Governance, Keio University, Tokyo 108-8345, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"042609","DOI":"10.1117\/1.JRS.11.042609","article-title":"Comprehensive survey of deep learning in remote sensing: Theories, tools, and challenges for the community","volume":"11","author":"Ball","year":"2017","journal-title":"J. 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