{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T23:07:01Z","timestamp":1779145621079,"version":"3.51.4"},"reference-count":48,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,16]],"date-time":"2020-09-16T00:00:00Z","timestamp":1600214400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministerio de Econom\u00eda y Empresa. European Regional Development Fund","award":["CTM2015-70446-R"],"award-info":[{"award-number":["CTM2015-70446-R"]}]},{"DOI":"10.13039\/501100004233","name":"Universitat Polit\u00e8cnica de Val\u00e8ncia","doi-asserted-by":"publisher","award":["PAID-10-19"],"award-info":[{"award-number":["PAID-10-19"]}],"id":[{"id":"10.13039\/501100004233","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A proposal is described for an underwater sensor combining an acoustic device with an optical one to automatically size juvenile bluefin tuna from a ventral perspective. Acoustic and optical information is acquired when the tuna are swimming freely and the fish cross our combined sensor\u2019s field of view. Image processing techniques are used to identify and classify fish traces in acoustic data (echogram), while the video frames are processed by fitting a deformable model of the fishes\u2019 ventral silhouette. Finally, the fish are sized combining the processed acoustic and optical data, once the correspondence between the two kinds of data is verified. The proposed system is able to automatically give accurate measurements of the tuna\u2019s Snout-Fork Length (SFL) and width. In comparison with our previously validated automatic sizing procedure with stereoscopic vision, this proposal improves the samples per hour of computing time by 7.2 times in a tank with 77 juveniles of Atlantic bluefin tuna (Thunnus thynnus), without compromising the accuracy of the measurements. This work validates the procedure for combining acoustic and optical data for fish sizing and is the first step towards an embedded sensor, whose electronics and processing capabilities should be optimized to be autonomous in terms of the power supply and to enable real-time processing.<\/jats:p>","DOI":"10.3390\/s20185294","type":"journal-article","created":{"date-parts":[[2020,9,16]],"date-time":"2020-09-16T10:30:12Z","timestamp":1600252212000},"page":"5294","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Automatic Bluefin Tuna Sizing with a Combined Acoustic and Optical Sensor"],"prefix":"10.3390","volume":"20","author":[{"given":"Pau","family":"Mu\u00f1oz-Benavent","sequence":"first","affiliation":[{"name":"Institute of Control Systems and Industrial Computing (AI2), Universitat Polit\u00e8cnica de Val\u00e8ncia (UPV), 46022 Val\u00e8ncia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8154-8259","authenticated-orcid":false,"given":"Vicente","family":"Puig-Pons","sequence":"additional","affiliation":[{"name":"Institut d\u2019Investigaci\u00f3 per a la Gesti\u00f3 Integrada de Zones Costaneres (IGIC), Universitat Polit\u00e8cnica de Val\u00e8ncia (UPV), 46022 Val\u00e8ncia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gabriela","family":"Andreu-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Institute of Control Systems and Industrial Computing (AI2), Universitat Polit\u00e8cnica de Val\u00e8ncia (UPV), 46022 Val\u00e8ncia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8882-866X","authenticated-orcid":false,"given":"V\u00edctor","family":"Espinosa","sequence":"additional","affiliation":[{"name":"Institut d\u2019Investigaci\u00f3 per a la Gesti\u00f3 Integrada de Zones Costaneres (IGIC), Universitat Polit\u00e8cnica de Val\u00e8ncia (UPV), 46022 Val\u00e8ncia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vicente","family":"Atienza-Vanacloig","sequence":"additional","affiliation":[{"name":"Institute of Control Systems and Industrial Computing (AI2), Universitat Polit\u00e8cnica de Val\u00e8ncia (UPV), 46022 Val\u00e8ncia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabel","family":"P\u00e9rez-Arjona","sequence":"additional","affiliation":[{"name":"Institut d\u2019Investigaci\u00f3 per a la Gesti\u00f3 Integrada de Zones Costaneres (IGIC), Universitat Polit\u00e8cnica de Val\u00e8ncia (UPV), 46022 Val\u00e8ncia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1212","DOI":"10.1093\/icesjms\/fsp079","article-title":"Target-strength, length, and tilt-angle measurements of Pacific saury (Cololabis saira) and Japanese anchovy (Engraulis japonicus) using an acoustic-optical system","volume":"66","author":"Sawada","year":"2009","journal-title":"ICES J. 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