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Regional substrate classification of Cook Strait, New Zealand, from textural image analysis of backscatter data
conference contribution
posted on 2023-05-24, 10:54 authored by Lamarche, G, Vanessa LucieerVanessa LucieerA comprehensive EM300 (32 kHz) multibeam survey of Cook Strait, New Zealand (~8500 km2) is used to generate a regional substrate classification map over a wide range of water depths, seafloor substrates and geological landforms using an automated mapping method based on the textural image analysis of backscatter data. We used the SonarScope® software to process the data, including signal corrections from sensor bias, specular reflection compensation and speckle noise filtering aiming at attenuating the effects of recording equipment, seafloor topography, and water column. This is required in order to obtain an image with a strongly attenuated specular reflection. Image segmentation of the merged backscatter and bathymetry layer is constrained using shape, compactness, and texture measures. The number of classes and their spatial distribution are statistically identified by employing an unsupervised fuzzy c-means (FCM) clustering algorithm to sediment samples, independent of the backscatter data. Classification is achieved from the overlay of the FCM result onto a segmented image and attributing segments with the FCM class.
History
Publication title
Geohab 2011: Development of New Methodologies to Map the Marine Environment in Support of Sustainable Ocean ManagementEditors
Aarno KotilainenDepartment/School
Institute for Marine and Antarctic StudiesPublisher
Geological Survey of FinlandPlace of publication
FinlandEvent title
Geohab 2011Event Venue
Helsinki, FinlandDate of Event (Start Date)
2011-05-03Date of Event (End Date)
2011-05-06Repository Status
- Restricted