Estimation and correction of geometric distortions in side-scan sonar images
Cobra, Daniel Távora de Queiroz
MetadataShow full item record
This thesis introduces a new procedure for the enhancement of acoustic images of the bottom of the sea produced by side-scan sonars. Specifically, it addresses the problem of estimating and correcting geometric distortions frequently observed in such images as a consequence of motion instabilities of the sonar array. This procedure estimates the geometric distortions from the image itself, without requiring any navigational or attitude measurements. A mathematical model for the distortions is derived from the geometry of the problem, and is applied to estimates of the local degree of geometric distortion obtained by cross-correlating segments of adjacent lines of the image. The model parameters are then recursively estimated through deterministic least-squares estimation. An alternative approach based on adaptive Kalman filtering is also proposed, providing a natural framework in which a priori information about the array dynamics may be easily incorporated. The estimates of the parameters of the distortion model are used to rectify the image, and may also be used for estimating the attitude parameters of the array. A simulation is employed to evaluate the effectiveness of this technique and examples of its application to high-resolution side-scan sonar images are provided.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution March 1990
Suggested CitationThesis: Cobra, Daniel Távora de Queiroz, "Estimation and correction of geometric distortions in side-scan sonar images", 1990-03, DOI:10.1575/1912/5426, https://hdl.handle.net/1912/5426
Showing items related by title, author, creator and subject.
Schanze, Julian J. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2013-02)Large-scale thermal forcing and freshwater fluxes play an essential role in setting temperature and salinity in the ocean. A number of recent estimates of the global oceanic freshwater balance as well as the global oceanic ...
Phenotypic diversity within two toxic dinoflagellate genera : environmental and transcriptomic studies of species diversity in Alexandrium and Gambierdiscus Pitz, Kathleen (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2016-09)Dinoflagellates are a diverse group of single-celled eukaryotic phytoplankton that are important for their unique genetics and molecular biology, the multitude of ecological roles they play, and the ability of multiple ...
Inferring ocean circulation during the Last Glacial Maximum and last deglaciation using data and models Amrhein, Daniel E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2016-09)Since the Last Glacial Maximum (LGM, ~ 20,000 years ago) air temperatures warmed, sea level rose roughly 130 meters, and atmospheric concentrations of carbon dioxide increased. This thesis combines global models and ...