{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:47:19Z","timestamp":1760240839221,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2019,9,27]],"date-time":"2019-09-27T00:00:00Z","timestamp":1569542400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003176","name":"Ministerio de Educaci\u00f3n, Cultura y Deporte","doi-asserted-by":"publisher","award":["TIN2016-76373-P"],"award-info":[{"award-number":["TIN2016-76373-P"]}],"id":[{"id":"10.13039\/501100003176","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["ERDF"],"award-info":[{"award-number":["ERDF"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008425","name":"Conseller\u00eda de Cultura, Educaci\u00f3n e Ordenaci\u00f3n Universitaria, Xunta de Galicia","doi-asserted-by":"publisher","award":["ED431G\/08","ED431C 2018\/2019"],"award-info":[{"award-number":["ED431G\/08","ED431C 2018\/2019"]}],"id":[{"id":"10.13039\/501100008425","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Over the last two decades, a wide range of applications have been developed from Light Detection and Ranging (LiDAR) point clouds. Most LiDAR-derived products require the distinction between ground and non-ground points. Because of this, ground filtering its being one of the most studied topics in the literature and robust methods are nowadays available. However, these methods have been designed to work with offline data and they are generally not well suited for real-time scenarios. Aiming to address this issue, this paper proposes an efficient method for ground filtering of airborne LiDAR data based on scan-line processing. In our proposal, an iterative 1-D spline interpolation is performed in each scan line sequentially. The final spline knots of a scan line are taken into account for the next scan line, so that valuable 2-D information is also considered without compromising computational efficiency. Points are labelled into ground and non-ground by analysing their residuals to the final spline. When tested against synthetic ground truth, the method yields a mean kappa value of 88.59% and a mean total error of 0.50%. Experiments with real data also show satisfactory results under visual inspection. Performance tests on a workstation show that the method can process up to 1 million points per second. The original implementation was ported into a low-cost development board to demonstrate its feasibility to run in embedded systems, where throughput was improved by using programmable logic hardware acceleration. Analysis shows that real-time filtering is possible in a high-end board prototype, as it can process the amount of points per second that current lightweight scanners acquire with low-energy consumption.<\/jats:p>","DOI":"10.3390\/rs11192256","type":"journal-article","created":{"date-parts":[[2019,9,27]],"date-time":"2019-09-27T11:14:35Z","timestamp":1569582875000},"page":"2256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Fast Ground Filtering of Airborne LiDAR Data Based on Iterative Scan-Line Spline Interpolation"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1486-8110","authenticated-orcid":false,"given":"Jorge","family":"Mart\u00ednez S\u00e1nchez","sequence":"first","affiliation":[{"name":"Centro Singular de Investigaci\u00f3n en Tecnolox\u00edas Intelixentes (CiTIUS), University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4719-8099","authenticated-orcid":false,"given":"\u00c1lvaro","family":"V\u00e1quez \u00c1lvarez","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica e Computaci\u00f3n, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4405-2924","authenticated-orcid":false,"given":"David","family":"L\u00f3pez Vilari\u00f1o","sequence":"additional","affiliation":[{"name":"Centro Singular de Investigaci\u00f3n en Tecnolox\u00edas Intelixentes (CiTIUS), University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6728-9350","authenticated-orcid":false,"given":"Francisco","family":"Fern\u00e1ndez Rivera","sequence":"additional","affiliation":[{"name":"Centro Singular de Investigaci\u00f3n en Tecnolox\u00edas Intelixentes (CiTIUS), University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5674-5162","authenticated-orcid":false,"given":"Jos\u00e9 Carlos","family":"Cabaleiro Dom\u00ednguez","sequence":"additional","affiliation":[{"name":"Centro Singular de Investigaci\u00f3n en Tecnolox\u00edas Intelixentes (CiTIUS), University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7622-4698","authenticated-orcid":false,"given":"Tom\u00e1s","family":"Fern\u00e1ndez Pena","sequence":"additional","affiliation":[{"name":"Centro Singular de Investigaci\u00f3n en Tecnolox\u00edas Intelixentes (CiTIUS), University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"833","DOI":"10.3390\/rs2030833","article-title":"Ground Filtering Algorithms for Airborne LiDAR Data: A Review of Critical Issues","volume":"2","author":"Meng","year":"2010","journal-title":"Remote Sensing"},{"key":"ref_2","first-page":"110","article-title":"DEM generation from laser scanner data using adaptive TIN models","volume":"33","author":"Axelsson","year":"2000","journal-title":"Int. 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