Gerald A. Hatcher
Christine J. Kranenburg
Jonathan A. Warrick
20221005
GNSS locations of seabed images collected at Looe Key, Florida, 2021
comma-delimited text file
data release
DOI:10.5066/P9WSF09G
Santa Cruz, California
U.S. Geological Survey - Pacific Coastal and Marine Science Center
https://doi.org/10.5066/P9WSF09G
Gerald A. Hatcher
Christine J. Kranenburg
Jonathan A. Warrick
Stephen T. Bosse
David G. Zawada
Kimberly K. Yates
Selena A. Johnson
2022
Overlapping seabed images and location data acquired using the SQUID-5 system at Looe Key, Florida, in July 2021, with derived point cloud, digital elevation model and orthomosaic of submerged topography
data release
DOI:10.5066/P9WSF09G
Santa Cruz, California
U.S. Geological Survey - Pacific Coastal and Marine Science Center
https://doi.org/10.5066/P9WSF09G
The text file "SQUID5_LKR_2021_Image_Locations.txt" provides the GNSS antenna location for underwater images collected at Looe Key, Florida, in July 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 EXIF headers due to decimal place limitations of the EXIF format.
The underwater images and associated location data were collected to provide high-resolution elevation data and precisely co-registered, full-color orthomosaic base maps for use in environmental assessment and monitoring of the coral reef and surrounding seafloor habitat. Additionally, the data were collected to evaluate their potential to improve USGS scientific efforts including seafloor elevation and stability modeling, and small-scale hydrodynamic flow modeling.
Additional information about the field activities from which these data were derived is available online at:
https://cmgds.marine.usgs.gov/fan_info.php?fan=2021-633-FA and https://cmgds.marine.usgs.gov/fan_info.php?fan=2021-301-FA
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
20210715
20210719
ground condition
None planned
-81.40955034
-81.40075500
24.54725136
24.54395879
USGS Metadata Identifier
USGS:90d9c75d-8256-46d6-8440-36ef400e5f3b
Marine Realms Information Bank (MRIB) keywords
seabed
Global Positioning System (GPS) observations
Data Categories for Marine Planning
Physical Habitats and Geomorphology
ISO 19115 Topic Category
oceans
elevation
USGS Thesaurus
reef ecosystems
geospatial datasets
remote sensing
visible light imaging
structure from motion
None
U.S. Geological Survey
USGS
Coastal and Marine Hazards and Resources Program
CMHRP
Pacific Coastal and Marine Science Center
PCMSC
St. Petersburg Coastal and Marine Science Center
SPCMSC
Geographic Names Information System (GNIS)
Looe Key
State of Florida
None
USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator of the dataset and in products derived from these data. This information is not intended for navigation purposes.
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060
831-460-4747
pcmsc_data@usgs.gov
Data collection was funded by the U.S. Geological Survey Pacific Coastal Marine Science Center and the U.S. Geological Survey Saint Petersburg Coastal and Marine Science Center. The authors would like to thank Dr. Jason Spadaro, Assistant Professor, Marine Science and Technology, College of the Florida Keys for installing calibration targets on the reef, Lisa Symons, Regional Response Coordinator, and the staff of the Eastern Region, Office of National Marine Sanctuaries, NOAA Florida Keys National Marine Sanctuary, for coordination efforts.
Microsoft Windows 10
Gerald A. Hatcher
Jonathan A. Warrick
Andrew C. Ritchie
Evan T. Dailey
David G. Zawada
Christine Kranenburg
Kimberly K. Yates
2020
Accurate bathymetric maps from underwater digital imagery without ground control
Hatcher, G.A., Warrick, J.A., Ritchie, A.C., Dailey, E.T., Zawada, D.G., Kranenburg, C., and Yates, K.K., 2020, Accurate bathymetric maps from underwater digital imagery without ground control: Frontiers in Marine Science, v. 7, art. 525, doi:10.3389/fmars.2020.00525
https://doi.org/10.3389/fmars.2020.00525
The accuracy of the position data used for SfM data processing is based on the accuracy of the post-processed GNSS navigation data, which produced a 10-Hz vehicle trajectory with an estimated 2-sigma accuracy of 10 cm horizontal and 15 cm vertical.
Note that the accuracy of the positions in the image EXIF headers are GNSS antenna positions and are limited to six decimal places, whereas the positions in the external navigation file are accurate to ten decimal places and are therefore highly recommended for use in SfM processing to produce the highest quality derived products.
All data fall within expected ranges.
Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details.
Positions provided in the navigation file (SQUID5_LKR_2021_Image_Locations.txt) have an estimated 2-sigma horizontal accuracy of 10 cm. The accuracy of the positions in the image EXIF headers are reduced due to field size limitations for storing latitude/longitude.
Positions provided in the navigation file (SQUID5_LKR_2021_Image_Locations.txt) have an estimated 2-sigma vertical accuracy of 15 cm.
SQUID-5 NAVIGATION PROCESSING
Raw GNSS data received by the antenna mounted atop the SQUID-5 were recorded at 10 Hz by a dual-frequency survey-grade GNSS receiver, which was post-processed and differentially corrected against a local base station located 14 Km from the survey site, in Novatel's GrafNav software (v. 8.80.2720; https://novatel.com/products/waypoint-post-processing-software/grafnav) to produce 10-Hz SQUID-5 trajectories.
The SQUID-5 trajectories, in combination with precisely recorded image capture event times, are used to generate SQUID-5 GNSS antenna positions at the moment of each image capture (SQUID5_LKR_2021_Image_Locations.txt). The positions in the SQUID-5 navigation file represent the position of the SQUID-5 GNSS antenna reference point (ARP), not the position of the cameras or features imaged. To determine actual image positions, photogrammetric software such as Agisoft Metashape can be used to apply the lever arm offsets (in the camera frame of reference) from the GNSS antenna reference point to the camera lens. Using this method the following values for each camera were calculated for x,y,z in units of meters. Camera 13, 0.028 m(x), 0.016 m(y), 0.822 m(z); Camera 39, 0.274 m(x), -0.106 m(y), 0.912 m(z); Camera 75, 0.128 m(x), 0.562 m(y), 0.741 m(z); Camera 82, -0.015 m(x), -0.570 m(y), 0.765 m(z).
20211110
Christine J. Kranenburg
U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
Cartographer
Physical and Mailing
600 4th Street South
St. Petersburg
FL
33701
USA
727-502-8000
ckranenburg@usgs.gov
Point
Point
93,885
0.0000000001
0.0000000001
Decimal degrees
North American Datum of 1983 (2011)
GRS 1980
6378137.000000
298.257222101
North American Datum 1983 (2011)
0.001
meters
Attribute values
SQUID5_LKR_2021_Image_Locations.txt
The comma-separated American Standard Code for Information Interchange (ASCII) text file, SQUID5_LKR_2021_Image_Locations.txt contains the post-processed towed surface vehicle navigation GNSS data (position of the towed surface vehicle at the moment of each image capture).
U.S. Geological Survey
ImageFile
File names of individual images. See the metadata file with the accompanying raw images for details on the file-naming convention.
U.S. Geological Survey
Unique number for raw image. See the metadata file with the accompanying raw images for details on the file-naming convention.
Latitude
Latitude of towed surface vehicle GNSS antenna position at the moment of each image capture, in decimal degrees NAD83(2011).
U.S. Geological Survey
24.54395879
24.54725136
decimal degrees
Longitude
Longitude of towed surface vehicle GNSS antenna position at the moment of each image capture, in decimal degrees NAD83(2011).
U.S. Geological Survey
-81.40955034
-81.40075500
decimal degrees
Altitude (NAD83 Ellipsoid Height)
Altitude of towed surface vehicle GNSS antenna position at the moment of each image capture, in meters above the NAD83 ellipsoid.
U.S. Geological Survey
-22.725
-21.026
SQUID-5 towed surface vehicle Navigation Data (SQUID5_LKR_2021_Image_Locations.txt) - Contains a comma-delimited text (TXT) file of the precise post-processed GNSS position of the towed surface vehicle at the precise initiation event time of each image capture; see the Entity_and_Attribute_Information section and Detailed_Description for more information on the variables reported in the TXT file, and see the Lineage section and towed surface vehicle NAVIGATION PROCESSING Process_Step for information on how to compute the precise image positions from the towed surface vehicle positions using photogrammetric software and applying lever arm offsets between the towed surface vehicle GNSS antenna and camera lens.
U.S. Geological Survey
U.S. Geological Survey - CMGDS
Mailing and Physical
2885 Mission Street
Santa Cruz
CA
95060
1-831-427-4747
pcmsc_data@usgs.gov
SQUID-5 towed surface vehicle Navigation Data (SQUID5_LKR_2021_Image_Locations.txt) - Contains a comma-delimited text (TXT) file of the precise post-processed GNSS position of the towed surface vehicle at the precise initiation event time of each image capture; see the Entity_and_Attribute_Information section and Detailed_Description for more information on the variables reported in the TXT file, and see the Lineage section and towed surface vehicle NAVIGATION PROCESSING Process_Step for information on how to compute the precise image positions from the towed surface vehicle positions using photogrammetric software and applying lever arm offsets between the towed surface vehicle GNSS antenna and camera lens.
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
comma-delimited text
Text (TXT) files can be opened directly with any text-editing software.
None
6.25
https://doi.org/10.5066/P9WSF09G
Antenna position data at the locations of image collection can be downloaded as a single text file by going to the Network_Resource_Name link and scrolling down to the Location-Elevation Data section.
none
20221005
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060
831-460-4747
pcmsc_data@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998