| Bathymetric digital elevation model (DEM) of Eastern Dry Rocks coral reef, Florida, 2021 |
SQUID-5 |
A digital elevation model (DEM) was created from underwater images collected at Eastern Dry Rocks coral reef near Key West, Florida, in May 2021 using the SQUID-5 camera system. The underwater images were processed using Structure-from-Motion (SfM) photogrammetry techniques into a classified two-class ('unclassified' and 'low noise') 3D point cloud. The DEM was derived in Metashape (ver. 1.6.5) from the point cloud, but it excludes the 'low noise' class. The DEM covers a rectangular area of seafloor approximately 800x160 meters (0.12 square kilometers) in size and was saved as a tiled GeoTIFF raster at 1-cm resolution. |
Gerald Hatcher |
| GNSS locations of seabed images collected at Eastern Dry Rocks coral reef, Florida, 2021 |
SQUID-5 |
This text file (SQUID5_EDR_2021_Image_Locations.txt) provides the GNSS antenna location for underwater images collected at Eastern Dry Rocks coral reef, near Key West, Florida, in May 2021, using the SQUID5 Structure-from-Motion (SfM) system, a towed-surface vehicle with five downward-looking underwater cameras developed by the U.S. Geological Survey. The GNSS antenna location for the time of each image capture is presented with greater precision than is stored in the individual image's EXIF header due to decimal place limitations of the EXIF format. |
Gerald Hatcher |
| Orthoimagery of Eastern Dry Rocks coral reef, Florida, 2021 |
SQUID-5 |
A seabed orthoimage was developed from underwater images collected at Eastern Dry Rocks coral reef near Key West, Florida, in May 2021 using the SQUID-5 camera system. The underwater images were processed using Structure-from-Motion (SfM) photogrammetry techniques. The orthoimage covers a rectangular area of seafloor approximately 800x160 meters (0.12 square kilometers) in size, and it was created using image-mosaicking methods and saved as a tiled, 5-mm resolution raster. |
Gerald Hatcher |
| Overlapping seabed images collected at Eastern Dry Rocks coral reef, Florida, 2021 |
SQUID-5 |
Underwater images totaling 138,733 in number were collected at Eastern Dry Rocks coral reef, near Key West, Florida, in May 2021, using the SQUID5 Structure-from-Motion (SfM) system, a towed-surface vehicle with five downward-looking underwater cameras developed by the U.S. Geological Survey. The images are organized in zipped files grouped by survey line. The SQUID-5 records images as TIFF (.tif) format to maintain the highest resolution and bit depth. Each image includes EXIF metadata, containing GNSS date, time, latitude, longitude, and altitude of the GNSS antenna mounted on the towed surface vehicle, copyright, keywords, and other fields. |
Gerald Hatcher |
| Point cloud data of Eastern Dry Rocks coral reef, Florida, 2021 |
SQUID-5 |
A three-dimensional point cloud (LAZ format) was developed from underwater images collected at Eastern Dry Rocks coral reef near Key West, Florida, in May 2021 using the SQUID-5 camera system and processed using Structure-from-Motion (SfM) photogrammetry techniques. Point cloud data include x,y,z positions, RGB colors, Metashape-computed confidence values, and a two-class classification ('unclassified' and 'low noise') derived from the confidence values. LAS (and its compressed form, LAZ) is an open format developed for the efficient use of point cloud lidar data. A description of the LAZ format and links to software tools for using LAZ files are provided at the USGS website: https://www.usgs.gov/news/3d-elevation-program-distributing-lidar-data-laz-format |
Gerald Hatcher |
