{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T06:28:29Z","timestamp":1776407309684,"version":"3.51.2"},"reference-count":22,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,7,17]],"date-time":"2018-07-17T00:00:00Z","timestamp":1531785600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Seventh Framework Programme","award":["618080"],"award-info":[{"award-number":["618080"]}]},{"DOI":"10.13039\/501100007757","name":"Agencia Canaria de Investigaci\u00f3n, Innovaci\u00f3n y Sociedad de la Informaci\u00f3n","doi-asserted-by":"publisher","award":["ProID2017010164"],"award-info":[{"award-number":["ProID2017010164"]}],"id":[{"id":"10.13039\/501100007757","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007757","name":"Agencia Canaria de Investigaci\u00f3n, Innovaci\u00f3n y Sociedad de la Informaci\u00f3n","doi-asserted-by":"publisher","award":["2017 PhD Training Program for Research Staff"],"award-info":[{"award-number":["2017 PhD Training Program for Research Staff"]}],"id":[{"id":"10.13039\/501100007757","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006368","name":"Universidad de Las Palmas de Gran Canaria","doi-asserted-by":"publisher","award":["2016 PhD Training Program for Research Staff"],"award-info":[{"award-number":["2016 PhD Training Program for Research Staff"]}],"id":[{"id":"10.13039\/501100006368","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The use of hyperspectral imaging (HSI) in the medical field is an emerging approach to assist physicians in diagnostic or surgical guidance tasks. However, HSI data processing involves very high computational requirements due to the huge amount of information captured by the sensors. One of the stages with higher computational load is the K-Nearest Neighbors (KNN) filtering algorithm. The main goal of this study is to optimize and parallelize the KNN algorithm by exploiting the GPU technology to obtain real-time processing during brain cancer surgical procedures. This parallel version of the KNN performs the neighbor filtering of a classification map (obtained from a supervised classifier), evaluating the different classes simultaneously. The undertaken optimizations and the computational capabilities of the GPU device throw a speedup up to 66.18\u00d7 when compared to a sequential implementation.<\/jats:p>","DOI":"10.3390\/s18072314","type":"journal-article","created":{"date-parts":[[2018,7,18]],"date-time":"2018-07-18T08:45:42Z","timestamp":1531903542000},"page":"2314","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Accelerating the K-Nearest Neighbors Filtering Algorithm to Optimize the Real-Time Classification of Human Brain Tumor in Hyperspectral Images"],"prefix":"10.3390","volume":"18","author":[{"given":"Giordana","family":"Florimbi","sequence":"first","affiliation":[{"name":"Department of Electrical, Computer and Biomedical Engineering, University of Pavia, 27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9794-490X","authenticated-orcid":false,"given":"Himar","family":"Fabelo","sequence":"additional","affiliation":[{"name":"Institute for Applied Microelectronics (IUMA), University of Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8437-8227","authenticated-orcid":false,"given":"Emanuele","family":"Torti","sequence":"additional","affiliation":[{"name":"Department of Electrical, Computer and Biomedical Engineering, University of Pavia, 27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2645-6749","authenticated-orcid":false,"given":"Raquel","family":"Lazcano","sequence":"additional","affiliation":[{"name":"Centre of Software Technologies and Multimedia Systems (CITSEM), Universidad Polit\u00e9cnica de Madrid (UPM), 28031 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5994-7440","authenticated-orcid":false,"given":"Daniel","family":"Madro\u00f1al","sequence":"additional","affiliation":[{"name":"Centre of Software Technologies and Multimedia Systems (CITSEM), Universidad Polit\u00e9cnica de Madrid (UPM), 28031 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7519-954X","authenticated-orcid":false,"given":"Samuel","family":"Ortega","sequence":"additional","affiliation":[{"name":"Institute for Applied Microelectronics (IUMA), University of Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0021-5808","authenticated-orcid":false,"given":"Ruben","family":"Salvador","sequence":"additional","affiliation":[{"name":"Centre of Software Technologies and Multimedia Systems (CITSEM), Universidad Polit\u00e9cnica de Madrid (UPM), 28031 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesco","family":"Leporati","sequence":"additional","affiliation":[{"name":"Department of Electrical, Computer and Biomedical Engineering, University of Pavia, 27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giovanni","family":"Danese","sequence":"additional","affiliation":[{"name":"Department of Electrical, Computer and Biomedical Engineering, University of Pavia, 27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abelardo","family":"B\u00e1ez-Quevedo","sequence":"additional","affiliation":[{"name":"Institute for Applied Microelectronics (IUMA), University of Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3784-5504","authenticated-orcid":false,"given":"Gustavo","family":"Callic\u00f3","sequence":"additional","affiliation":[{"name":"Institute for Applied Microelectronics (IUMA), University of Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eduardo","family":"Ju\u00e1rez","sequence":"additional","affiliation":[{"name":"Centre of Software Technologies and Multimedia Systems (CITSEM), Universidad Polit\u00e9cnica de Madrid (UPM), 28031 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2411-9132","authenticated-orcid":false,"given":"C\u00e9sar","family":"Sanz","sequence":"additional","affiliation":[{"name":"Centre of Software Technologies and Multimedia Systems (CITSEM), Universidad Polit\u00e9cnica de Madrid (UPM), 28031 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roberto","family":"Sarmiento","sequence":"additional","affiliation":[{"name":"Institute for Applied Microelectronics (IUMA), University of Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1080\/05704928.2013.838678","article-title":"Hyperspectral Imaging in the Medical Field: Present and Future","volume":"49","author":"Calin","year":"2013","journal-title":"Appl. Spectrosc. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"10901","DOI":"10.1117\/1.JBO.19.1.010901","article-title":"Medical hyperspectral imaging: A review","volume":"19","author":"Lu","year":"2014","journal-title":"J. Biomed. Opt."},{"key":"ref_3","unstructured":"Chang, C.-I. (2003). Hyperspectral Imaging: Techniques for Spectral Detection and Classification, Springer Science & Business Media."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Akbari, H., and Kosugi, Y. (2009). Hyperspectral imaging: A new modality in surgery. Recent Advances in Biomedical Engineering, InTech.","DOI":"10.5772\/7478"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"40","DOI":"10.1109\/MEMB.2004.1360407","article-title":"A hyperspectral imaging system for in vivo optical diagnostics","volume":"23","year":"2004","journal-title":"Eng. Med. Biol. Mag. IEEE"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"439","DOI":"10.4161\/cbt.6.3.4018","article-title":"Medical hyperspectral imaging to facilitate residual tumor identification during surgery","volume":"6","author":"Panasyuk","year":"2007","journal-title":"Cancer Biol. Ther."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1059","DOI":"10.1007\/s11548-014-0989-9","article-title":"Intraoperative visualization of cerebral oxygenation using hyperspectral image data: A two-dimensional mapping method","volume":"9","author":"Mori","year":"2014","journal-title":"Int. J. Comput. Assist. Radiol. Surg."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1109\/MSP.2011.940409","article-title":"Parallel Hyperspectral Image and Signal Processing","volume":"28","author":"Plaza","year":"2011","journal-title":"IEEE Signal Process. Mag."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"S140","DOI":"10.1016\/j.ijsu.2016.11.044","article-title":"Others Intra-operative hyperspectral imaging for brain tumour detection and delineation: Current progress on the HELICoid project","volume":"36","author":"Kabwama","year":"2016","journal-title":"Int. J. Surg."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Salvador, R., Ortega, S., Madro\u00f1al, D., Fabelo, H., Lazcano, R., Marrero, G., Ju\u00e1rez, E., Sarmiento, R., and Sanz, C. (2017, January 15\u201317). HELICoiD: Interdisciplinary and collaborative project for real-time brain cancer detection. Proceedings of the ACM International Conference on Computing Frontiers 2017, Siena, Italy.","DOI":"10.1145\/3075564.3076262"},{"key":"ref_11","first-page":"166","article-title":"Hyperspectral Imaging as A Novel Instrument for Intraoperative Brain Tumor Detection","volume":"27","author":"Szolna","year":"2016","journal-title":"Neurocirugia"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Fabelo, H., Ortega, S., Lazcano, R., Madro\u00f1al, D., Callic\u00f3 G, M., Ju\u00e1rez, E., Salvador, R., Bulters, D., Bulstrode, H., and Szolna, A. (2018). An intraoperative visualization system using hyperspectral imaging to aid in brain tumor delineation. Sensors, 18.","DOI":"10.3390\/s18020430"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Kuo, B.C., Yang, J.M., Sheu, T.W., and Yang, S.W. (2008, January 7\u201311). Kernel-based KNN and Gaussian classifiers for hyperspectral image classification. Proceedings of the International Geoscience and Remote Sensing Symposium (IGARSS), Boston, MA, USA.","DOI":"10.1109\/IGARSS.2008.4779167"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1123","DOI":"10.1007\/s10596-016-9580-5","article-title":"OpenMP and CUDA simulations of Sella Zerbino Dam break on unstructured grids","volume":"20","author":"Petaccia","year":"2016","journal-title":"Comput. Geosci."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Florimbi, G., Torti, E., Danese, G., and Leporati, F. (2017, January 6\u20138). High Performant Simulations of Cerebellar Golgi Cells Activity. Proceedings of the 2017 25th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (PDP), ST. Peterburg, Russia.","DOI":"10.1109\/PDP.2017.91"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Wang, Y., Li, L., Wang, J., and Tian, R. (2016, January 17\u201319). GPU Acceleration of Smoothed Particle Hydrodynamics for the Navier-Stokes Equations. Proceedings of the 2016 24th Euromicro International Conference on Parallel, Distributed, and Network-Based Processing, Heraklion, Greece.","DOI":"10.1109\/PDP.2016.28"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"753","DOI":"10.1007\/s11554-017-0703-6","article-title":"Parallel real-time virtual dimensionality estimation for hyperspectral images","volume":"14","author":"Torti","year":"2018","journal-title":"J. Real Time Image Process."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/j.micpro.2018.06.005","article-title":"Acceleration of brain cancer detection algorithms during surgery procedures using GPUs","volume":"61","author":"Torti","year":"2018","journal-title":"Microprocess. Microsyst."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Garcia, V., Debreuve, E., Nielsen, F., and Barlaud, M. (2010, January 26\u201329). K-nearest neighbor search: Fast GPU-based implementations and application to high-dimensional feature matching. Proceedings of the 2010 IEEE International Conference on Image Processing, Hong Kong, China.","DOI":"10.1109\/ICIP.2010.5654017"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Chen, G., Ding, Y., and Shen, X. (2017, January 19\u201322). Sweet KNN: An efficient KNN on GPU through reconciliation between redundancy removal and regularity. Proceedings of the 2017 IEEE 33rd International Conference on Data Engineering (ICDE), San Diego, CA, USA.","DOI":"10.1109\/ICDE.2017.116"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s11220-015-0126-z","article-title":"Spectral\u2013Spatial Hyperspectral Image Classification Based on KNN","volume":"17","author":"Huang","year":"2016","journal-title":"Sens. Imaging"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Fabelo, H., Ortega, S., Ravi, D., Kiran, B.R., Sosa, C., Bulters, D., Callic\u00f3, G.M., Bulstrode, H., Szolna, A., and Pi\u00f1eiro, J.F. (2018). Spatio-spectral classification of hyperspectral images for brain cancer detection during surgical operations. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0193721"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/7\/2314\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:12:33Z","timestamp":1760195553000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/7\/2314"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,7,17]]},"references-count":22,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2018,7]]}},"alternative-id":["s18072314"],"URL":"https:\/\/doi.org\/10.3390\/s18072314","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,7,17]]}}}