{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T01:43:43Z","timestamp":1768787023473,"version":"3.49.0"},"reference-count":18,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,5,24]],"date-time":"2022-05-24T00:00:00Z","timestamp":1653350400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"IVACE (Valencian Institute of Business Competitiveness)","award":["IMAMCN\/2021\/1"],"award-info":[{"award-number":["IMAMCN\/2021\/1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Computers"],"abstract":"<jats:p>Several calibration algorithms use spheres as calibration tokens because of the simplicity and uniform shape that a sphere presents across multiple views, along with the simplicity of its construction. Among the alternatives are the use of complex 3D tokens with reference marks, usually complex to build and analyze with the required accuracy; or the search of common features in scene images, with this task being of high complexity too due to perspective changes. Some of the algorithms using spheres rely on the estimation of the sphere center projection obtained from the camera images to proceed. The computation of these projection points from the sphere silhouette on the images is not straightforward because it does not match exactly the silhouette centroid. Thus, several methods have been developed to cope with this calculation. In this work, a simple and fast numerical method adapted to precisely compute the sphere center projection for these algorithms is presented. The benefits over other similar existing methods are its ease of implementation and that it presents less sensibility to segmentation issues. Other possible applications of the proposed method are presented too.<\/jats:p>","DOI":"10.3390\/computers11060084","type":"journal-article","created":{"date-parts":[[2022,5,24]],"date-time":"2022-05-24T22:04:06Z","timestamp":1653429846000},"page":"84","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Improving Multi-View Camera Calibration Using Precise Location of Sphere Center Projection"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9059-0128","authenticated-orcid":false,"given":"Alberto J.","family":"Perez","sequence":"first","affiliation":[{"name":"Instituto Tecnol\u00f3gico de Inform\u00e1tica (ITI), Universidad Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"},{"name":"Departamento de Inform\u00e1tica de Sistemas y Computadores (DISCA), Universidad Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4195-9491","authenticated-orcid":false,"given":"Javier","family":"Perez-Soler","sequence":"additional","affiliation":[{"name":"Instituto Tecnol\u00f3gico de Inform\u00e1tica (ITI), Universidad Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6506-090X","authenticated-orcid":false,"given":"Juan-Carlos","family":"Perez-Cortes","sequence":"additional","affiliation":[{"name":"Instituto Tecnol\u00f3gico de Inform\u00e1tica (ITI), Universidad Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"},{"name":"Departamento de Inform\u00e1tica de Sistemas y Computadores (DISCA), Universidad Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jose-Luis","family":"Guardiola","sequence":"additional","affiliation":[{"name":"Instituto Tecnol\u00f3gico de Inform\u00e1tica (ITI), Universidad Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1012","DOI":"10.1007\/s11263-018-1139-6","article-title":"An Exact Robust Method to Localize a Known Sphere by Means of One Image","volume":"127","author":"Penne","year":"2019","journal-title":"Int. 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