{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T13:40:29Z","timestamp":1777729229346,"version":"3.51.4"},"reference-count":36,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,12,6]],"date-time":"2017-12-06T00:00:00Z","timestamp":1512518400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>The clover-grass ratio is an important factor in composing feed ratios for livestock. Cameras in the field allow the user to estimate the clover-grass ratio using image analysis; however, current methods assume the total dry matter is known. This paper presents the preliminary results of an image analysis method for non-destructively estimating the total dry matter of clover-grass. The presented method includes three steps: (1) classification of image illumination using a histogram of the difference in excess green and excess red; (2) segmentation of clover and grass using edge detection and morphology; and (3) estimation of total dry matter using grass coverage derived from the segmentation and climate parameters. The method was developed and evaluated on images captured in a clover-grass plot experiment during the spring growing season. The preliminary results are promising and show a high correlation between the image-based total dry matter estimate and the harvested dry matter     (  R 2  = 0.93 )     with an RMSE of 210 kg ha      \u2212 1     .<\/jats:p>","DOI":"10.3390\/jimaging3040059","type":"journal-article","created":{"date-parts":[[2017,12,6]],"date-time":"2017-12-06T11:29:36Z","timestamp":1512559776000},"page":"59","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Preliminary Results of Clover and Grass Coverage and Total Dry Matter Estimation in Clover-Grass Crops Using Image Analysis"],"prefix":"10.3390","volume":"3","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8773-635X","authenticated-orcid":false,"given":"Anders","family":"Mortensen","sequence":"first","affiliation":[{"name":"Department of Agroecology, Aarhus University, Fors\u00f8gsvej 1, Flakkebjerg, 4200 Slagese, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Henrik","family":"Karstoft","sequence":"additional","affiliation":[{"name":"Department of Engineering, Aarhus University, Finlandsgade 22, 8200 Aarhus N, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karen","family":"S\u00f8egaard","sequence":"additional","affiliation":[{"name":"Department of Agroecology, Aarhus University, Blichers All\u00e9 20, 8830 Tjele, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1432-4781","authenticated-orcid":false,"given":"Ren\u00e9","family":"Gislum","sequence":"additional","affiliation":[{"name":"Department of Agroecology, Aarhus University, Fors\u00f8gsvej 1, Flakkebjerg, 4200 Slagese, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1329-1674","authenticated-orcid":false,"given":"Rasmus","family":"J\u00f8rgensen","sequence":"additional","affiliation":[{"name":"Department of Engineering, Aarhus University, Finlandsgade 22, 8200 Aarhus N, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,6]]},"reference":[{"key":"ref_1","first-page":"139","article-title":"Nitrogen fertilization of grass\/clover swards under cutting or grazing by dairy cows","volume":"59","year":"2009","journal-title":"Acta Agric. 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