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SQUID-5 structure-from-motion point clouds, bathymetric maps, orthomosaics, and underwater photos of coral reefs in Florida, 2019

May 1, 2020

The new structure-from-motion (SfM) quantitative underwater imaging device with five cameras (SQUID-5) was tested in July 2019 at Crocker Reef in the Florida Keys. The SQUID-5 was developed to meet the unique challenges of collecting SfM underwater imagery, including multiple cameras with different perspectives, accurate geographic locations of images, accurate and precise scaling of derived surface models, imagery coverage, and overlap geometry. Images were collected in tightly coupled quintets over varying benthic features, such as live and senile coral, sand waves, and rubble. The SQUID-5 platform was towed by the R/V Sallenger (8 m enclosed cabin ship) equipped with real-time acquisition monitoring. The primary purpose of the field experiment was to evaluate SQUID-5's capabilities and limitations, and to determine its potential for generating data products of value to reef scientists. Survey locations were chosen based on their history of scientific investigations, including recently installed benthic survey monuments, and repeated studies of sediment elevation table (SET) stations. Images were collected over two SET stations to assess SfM product accuracy and precision. Images were also collected over areas of Crocker Reef to assess the SfM products ability to accurately map complex benthic topographies.