title: Looking inside the Ocean: Toward an Autonomous Imaging System for Monitoring Gelatinous Zooplankton.
abstract: Marine plankton abundance and dynamics in the open and interior ocean is still an unknown field. The knowledge of gelatinous zooplankton distribution is especially challenging, because this type of plankton has a very fragile structure and cannot be directly sampled using traditional net based techniques. To overcome this shortcoming, Computer Vision techniques can be successfully used for the automatic monitoring of this group.This paper presents the GUARD1 imaging system, a low-cost stand-alone instrument for underwater image acquisition and recognition of gelatinous zooplankton, and discusses the performance of three different methodologies, Tikhonov Regularization, Support Vector Machines and Genetic Programming, that have been compared in order to select the one to be run onboard the system for the automatic recognition of gelatinous zooplankton. The performance comparison results highlight the high accuracy of the three methods in gelatinous zooplankton identification, showing their good capability in robustly selecting relevant features. In particular, Genetic Programming technique achieves the same performances of the other two methods by using a smaller set of features, thus being the most efficient in avoiding computationally consuming preprocessing stages, that is a crucial requirement for running on an autonomous imaging system designed for long lasting deployments, like the GUARD1. The Genetic Programming algorithm has been installed onboard the system, that has been operationally tested in a two-months survey in the Ligurian Sea, providing satisfactory results in terms of monitoring and recognition performances.
authors.affiliation: Institute of Marine Sciences (ISMAR) in La Spezia, National Research Council of Italy (CNR), Forte Santa Teresa, 19032 Pozzuolo di Lerici (SP), Italy. lorenzo.corgnati@sp.ismar.cnr.it.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Corgnati
authors.affiliation: Institute of Marine Sciences (ISMAR) in La Spezia, National Research Council of Italy (CNR), Forte Santa Teresa, 19032 Pozzuolo di Lerici (SP), Italy. simone.marini@sp.ismar.cnr.it.
authors.forename: Simone
authors.initials: S
authors.lastname: Marini
authors.affiliation: Institute of Marine Sciences (ISMAR) in La Spezia, National Research Council of Italy (CNR), Forte Santa Teresa, 19032 Pozzuolo di Lerici (SP), Italy. luca.mazzei@sp.ismar.cnr.it.
authors.forename: Luca
authors.initials: L
authors.lastname: Mazzei
authors.affiliation: OnAir srl, Via Carlo Barabino 26/4B, 16129 Genova, Italy. ennio.ottaviani@onairweb.com.
authors.forename: Ennio
authors.initials: E
authors.lastname: Ottaviani
authors.affiliation: Institute of Marine Sciences (ISMAR) in La Spezia, National Research Council of Italy (CNR), Forte Santa Teresa, 19032 Pozzuolo di Lerici (SP), Italy. stefano.aliani@sp.ismar.cnr.it.
authors.forename: Stefano
authors.initials: S
authors.lastname: Aliani
authors.affiliation: Institute of Marine Sciences (ISMAR) in La Spezia, National Research Council of Italy (CNR), Forte Santa Teresa, 19032 Pozzuolo di Lerici (SP), Italy. a.conversi@ismar.cnr.it.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Conversi
authors.affiliation: Institute of Marine Sciences (ISMAR) in La Spezia, National Research Council of Italy (CNR), Forte Santa Teresa, 19032 Pozzuolo di Lerici (SP), Italy. annalisa.griffa@sp.ismar.cnr.it.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Griffa
mesh_terms: D000465:Algorithms; D000818:Animals; D005780:Gelatin / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D009792:Oceans and Seas; D015048:Zooplankton / Q000502:physiology*
chemical_list: D005780:Gelatin
keywords: GUARD1; autonomous underwater imaging; content-based image recognition; feature selection; gelatinous zooplankton