HR: 16:35h
AN: OS42B-02 [Abstracts]
TI: Some Processing and Dynamic-Range Issues in Side-Scan Sonar Work
AU: Asper, V L
EM: vernon.asper@usm.edu
AF: University of Southern Mississippi, Department of Marine Science
1020 Balch Blvd, Stennis Space Center, MS 39529, United States
AU: * Caruthers, J W
EM: jerald.caruthers@usm.edu
AF: University of Southern Mississippi, Department of Marine Science
1020 Balch Blvd, Stennis Space Center, MS 39529, United States
AB:
Often side-scan sonar data are collected in such a way that they afford little opportunity to do more than simply
display them as images. These images are often limited in dynamic range and stored only in an 8-bit tiff format of
numbers representing less than true intensity values. Furthermore, there is little prior knowledge during a survey
of the best range in which to set those eight bits. This can result in clipped strong targets and/or the depth of
shadows so that the bits that can be recovered from the image are not fully representative of target or bottom
backscatter strengths. Several top-of-the-line sonars do have a means of logging high-bit-rate digital data
(sometimes only as an option), but only dedicated specialists pay much attention to such data, if they record them
at all. Most users of side-scan sonars are interested only in the images. Discussed in this paper are issues
related to storing and processing of high-bit-rate digital data to preserve their integrity for future enhanced, after-
the-fact use and ability to recover actual backscatter strengths. This papers discusses issues in the use high-bit-
rate, digital side-scan sonar data. This work was supported by the Office of Naval Research, Code 321OA, and
the Naval Oceanographic Office, Mine Warfare Program.
DE: 3045 Seafloor morphology, geology, and geophysics
SC: Ocean Sciences [OS]
MN: 2007 Joint Assembly