{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:01:29Z","timestamp":1760241689827,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,7,24]],"date-time":"2018-07-24T00:00:00Z","timestamp":1532390400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Norges Forskningsr\u00e5d","doi-asserted-by":"publisher","award":["221073"],"award-info":[{"award-number":["221073"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Algorithms"],"abstract":"<jats:p>Discretized image signals might have a lower dynamic range than the display. Because of this, false contours might appear when the image has the same pixel value for a larger region and the distance between pixel levels reaches the noticeable difference threshold. There have been several methods aimed at approximating the high bit depth of the original signal. Our method models a region with a bended plate model, which leads to the biharmonic equation. This method addresses several new aspects: the reconstruction of non-continuous regions when foreground objects split the area into separate regions; the incorporation of confidence about pixel levels, making the model tunable; and the method gives a physics-inspired way to handle local maximal\/minimal regions. The solution of the biharmonic equation yields a smooth high-order signal approximation and handles the local maxima\/minima problems.<\/jats:p>","DOI":"10.3390\/a11080110","type":"journal-article","created":{"date-parts":[[2018,7,24]],"date-time":"2018-07-24T11:00:07Z","timestamp":1532430007000},"page":"110","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Image De-Quantization Using Plate Bending Model"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9723-5532","authenticated-orcid":false,"given":"David","family":"V\u00f6lgyes","sequence":"first","affiliation":[{"name":"Department of Computer Science, Norwegian University of Science and Technology, 2815 Gj\u00f8vik, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1346-7721","authenticated-orcid":false,"given":"Anne Catrine Tr\u00e6gde","family":"Martinsen","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Oslo, 0316 Oslo, Norway"},{"name":"Department of Diagnostic Physics, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7238-0327","authenticated-orcid":false,"given":"Arne","family":"Stray-Pedersen","sequence":"additional","affiliation":[{"name":"Department of Forensic Sciences, Oslo University Hospital, 0424 Oslo, Norway"},{"name":"Institute of Clinical Medicine, University of Oslo, 0318 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7648-6081","authenticated-orcid":false,"given":"Dag","family":"Waaler","sequence":"additional","affiliation":[{"name":"Department of Health Sciences in Gj\u00f8vik, Norwegian University of Science and Technology, 2803 Gj\u00f8vik, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9797-5821","authenticated-orcid":false,"given":"Marius","family":"Pedersen","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Norwegian University of Science and Technology, 2815 Gj\u00f8vik, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1109\/TCOM.1964.1088973","article-title":"Dither Signals and Their Effect on Quantization Noise","volume":"12","author":"Schuchman","year":"1964","journal-title":"IEEE Trans. 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