Geometric Corrections on Sidescan Sonar Images Based on Bathymetry. Application with SeaMARC II and Sea Beam Data
Abstract
Acoustic backscatter images of the seafloor obtained with sidescan sonar systems are displayed most often using a flat bottom assumption. Whenever this assumption is not valid, pixels are mapped incorrectly in the image frame, yielding distorted representations of the seafloor. Here, such distortions are corrected by using an appropriate representation of the relief, as measured by the sonar that collected the acoustic backscatter information. In addition, all spatial filtering operations required in the pixel relocation process take the sonar geometry into account. Examples of the process are provided by data collected in the Northeastern Pacific over Fieberling Guyot with the SeaMARC II bathymetric sidescan sonar system and the Sea Beam multibeam echo-sounder. The nearly complete (90%) Sea Beam bathymetry coverage of the Guyot serves as a reference to quantify the distortions found in the backscatter images and to evaluate the accuracy of the corrections performed with SeaMARC II bathymetry. As a byproduct, the processed SeaMARC II bathymetry and the Sea Beam bathymetry adapted to the SeaMARC II sonar geometry exhibit a 35m mean-square difference over the entire area surveyed.
Department
Center for Coastal and Ocean Mapping
Publication Date
10-1994
Volume
16, Issue 5
Journal Title
Marine Geophysical Researches
Pages
365-383
Publisher Place
New York, NY, USA
Publisher
Springer
Digital Object Identifier (DOI)
10.1007/BF01203973
Document Type
Journal Article
Recommended Citation
P. Cervenka, C. De Moustier, and P. F. Lonsdale, "Geometric corrections on sidescan sonar images based on bathymetry. Application with SeaMARC II and sea beam data," Marine Geophysical Researches, vol. 16, no. 5, pp. 365–383, Oct. 1994.