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www.sea-technology.com September 2015 / st 11 for acquisition of soundings in areas not accessible to the survey vessel. The side-looking MBES transducer orientation was employed extensively in shallow, debris-strewn, near- shore areas. The feld team documented the shoreline employing a GoPro camera mounted at the location of the MBES trans- ducer pole. Each day, the GoPro camera was time-synced with the survey vessel's navigation system, an Appla- nix POS MV, and was employed to capture shoreline video at a rate of 1 Hz as the vessel navigated the near- shore shallows. The GoPro camera was operated con- currently with side-looking MBES acquisition at high tide, with the camera oriented toward the shoreline in the same direction that the soundings were projected. GoPro videos of the shoreline were also acquired near low tide to assist with classifcation of features in the intertidal zone. Additional still photographs of signifcant shoreline and high-water features were captured with a point- and-shoot camera whose time and date were also synced with the GPS for georeferencing during post- processing. The side-looking MBES combined with the shoreline imagery proved to be a vital and cost-effec- tive tool in properly attributing shoreline features. Ancillary Data Toolbox Prior to editing SSS and MBES data, the photo and video images were processed into geographically referenced products. GPX (GPS exchange format) track logs correlating to the video run time were generated from navigation data that were output daily employing Applanix POSPac MMS software. Still photos were georeferenced by synchronizing the Exif (exchangeable image fle format) headers imbedded in the photos with the GPX track log. GoPro videos were reformatted to display a time and date header on each picture frame, and track- lines that correlated to the start and stop times of the GoPro videos were generated from the GPX track logs. The georeferenced still photos and the time-synced video tracklines were imported into Google Earth for geospatial visualization and saved as KML and KMZ fles, respectively. The geo- referenced images were opened by clicking on a specifc camera icon in Google Earth. Once conversion and reformatting were com- pleted, the video, still camera photos and vessel tracklines could be quickly recalled via georeferenced hyperlinks embedded in the Global Mapper environment and displayed in different formats, such as Google Earth's KML/KMZ format (video tracklines and still photo positions) and Apple's QuickTime movie format (video viewing). With the Google Earth time-slider tool, the survey vessel position can be moved forward and backward along its respective trackline. The vessel position and corresponding time as displayed on the Google Earth time-slider bar are in sync with the time displayed on the header of the GoPro video opened in Apple QuickTime. Pre- and post-Hurricane Sandy aerial and satellite imagery were also utilized during data process- ing. The Google Earth "Show Historical Imagery" tool was used to review shoreline changes spanning past decades up to present day, including post-Sandy imagery. The aerial and satellite imagery were benefcial in identifying the ori- gin and transitory states of modern day ruins and wreckage, which assisted in feature classifcation and attribution. (Top) A subset of the wreck- and ob- struction-laden seafoor in Jamaica Bay shown in a gridded 50-cm bathy- metric surface colored by depth. (Middle) The time stamp embedded in the GoPro video was synced with the time-slider bar in Google Earth, which was used to correlate the video to the survey vessel's trackline position. (Bot- tom) Floating docks and support pil- ings in the MBES point cloud fagged as Examined soundings (top), and the docks as recorded on the surface with the GoPro camera (bottom).