{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,27]],"date-time":"2025-10-27T20:37:04Z","timestamp":1761597424463,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2013,4,26]],"date-time":"2013-04-26T00:00:00Z","timestamp":1366934400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The aim of this research is an improvement of plant seedling recognition by two new approaches of shape feature generation based on plant silhouettes. Experiments show that the proposed feature sets possess value in plant recognition when compared with other feature sets. Both methods approximate a distance distribution of an object, either by resampling or by approximation of the distribution with a high degree Legendre polynomial. In the latter case, the polynomial coefficients constitute a feature set. The methods have been tested through a discrimination process where two similar plant species are to be distinguished into their respective classes. The used performance assessment is based on the classification accuracy of 4 different classifiers (a k-Nearest Neighbor, Naive-Bayes, Linear Support Vector Machine, Nonlinear Support Vector Machine). Another set of 21 well-known shape features described in the literature is used for comparison. The used data consisted of 139 samples of cornflower (Centaura cyanus L.) and 63 samples of nightshade (Solanum nigrum L.). The highest discrimination accuracy was achieved with the Legendre Polynomial feature set and amounted to 97.5%. This feature set consisted of 10 numerical values. Another feature set consisting of 21 common features achieved an accuracy of 92.5%. The results suggest that the Legendre Polynomial feature set can compete with or outperform the commonly used feature sets.<\/jats:p>","DOI":"10.3390\/s130505585","type":"journal-article","created":{"date-parts":[[2013,4,26]],"date-time":"2013-04-26T11:27:28Z","timestamp":1366975648000},"page":"5585-5602","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Seedling Discrimination with Shape Features Derived from a Distance Transform"],"prefix":"10.3390","volume":"13","author":[{"given":"Thomas","family":"Giselsson","sequence":"first","affiliation":[{"name":"Institute of Chemical Engineering, Biotechnology and Environmental Technology,University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark"}]},{"given":"Henrik","family":"Midtiby","sequence":"additional","affiliation":[{"name":"Institute of Chemical Engineering, Biotechnology and Environmental Technology,University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark"}]},{"given":"Rasmus","family":"J\u00f8rgensen","sequence":"additional","affiliation":[{"name":"Institute of Chemical Engineering, Biotechnology and Environmental Technology,University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark"}]}],"member":"1968","published-online":{"date-parts":[[2013,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"252","DOI":"10.1614\/WS-04-068R1","article-title":"Symposium Site-specific weed management: Sensing requirements\u2014what do we need to see?","volume":"53","author":"Brown","year":"2005","journal-title":"Weed Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"259","DOI":"10.13031\/2013.27838","article-title":"Color indices for weed identification under various soil, residue, and lighting conditions","volume":"38","author":"Woebbecke","year":"1995","journal-title":"Trans. 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