Metadata: Identification_Information: Citation: Citation_Information: Originator: Christine J. Kranenburg Originator: Gerald A. Hatcher Originator: Jonathan A. Warrick Publication_Date: 20240628 Title: Orthoimagery of Looe Key, Florida, 2022 Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1QRS3SK Publication_Information: Publication_Place: St. Petersburg, FL Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P1QRS3SK Larger_Work_Citation: Citation_Information: Originator: Christine J. Kranenburg Originator: Gerald A. Hatcher Originator: David G. Zawada Originator: Jonathan A. Warrick Originator: Kimberly K. Yates Originator: Selena A. Johnson Publication_Date: 20240628 Title: Underwater Photogrammetry Products of Looe Key, Florida From Images Acquired Using the SQUID-5 System in July 2022 Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1QRS3SK Publication_Information: Publication_Place: St. Petersburg, FL Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P1QRS3SK Description: Abstract: A seabed orthoimage was developed from underwater images collected at Looe Key (LKR), Florida, in July 2022 using the SfM (Structure-from-Motion) Quantitative Underwater Imaging Device with 5 cameras (SQUID-5) system. The underwater images were processed using SfM photogrammetry techniques. The orthoimage covers a rectangular area of seafloor approximately 850x160 meters (m) (0.13 square kilometers [km]) in size. It was created using image-averaging methods and saved as Geographic Tagged Image File Format (GeoTIFF) rasters at 5-millimeter (mm) resolution, in a 5-by-2 tile index grid. A 25-centimeter (cm) resolution "quicklook" version of this orthoimage is also included in this data release so that users can quickly view the entire dataset at a lower resolution before downloading the higher resolution raster tiles. Purpose: The underwater images and associated location data were collected to provide high-resolution elevation data and precisely co-registered, full-color orthoimage 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 U.S. Geological Survey (USGS) scientific efforts including seafloor elevation and stability modeling, and small-scale hydrodynamic flow modeling. Supplemental_Information: Each data collection is recorded in the USGS Coastal and Marine Hazards Resources Program (CMHRP) Coastal and Marine Geoscience Data System (CMGDS) field activity database and is assigned a Field Activity Number (FAN). 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=2022-314-FA Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20220712 Ending_Date: 20220716 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -81.41016166 East_Bounding_Coordinate: -81.40065243 North_Bounding_Coordinate: 24.54779751 South_Bounding_Coordinate: 24.54442068 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:f13eaf9d-3e4f-41f7-bb7d-17034d612907 Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: seabed Theme_Keyword: coral reefs Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: Physical Habitats and Geomorphology Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: elevation Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: reef ecosystems Theme_Keyword: geospatial datasets Theme_Keyword: remote sensing Theme_Keyword: visible light imaging Theme_Keyword: structure from motion Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: Pacific Coastal and Marine Science Center Theme_Keyword: PCMSC Theme_Keyword: St. Petersburg Coastal and Marine Science Center Theme_Keyword: SPCMSC Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: Looe Key Place_Keyword: State of Florida Access_Constraints: None Use_Constraints: 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. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Person: SPCMSC Data Management Group Contact_Address: Address_Type: mailing and physical Address: 600 4th St South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: gs-g-spcmsc_data_inquiries@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: LKR22_orthoavg_hirez_webview2.png Browse_Graphic_File_Description: Sample view of larger high resolution (5-mm) orthoaverage image (tile B-1) in Portable Network Graphics (PNG) file format. The image is available on the webpage for this data release. Browse_Graphic_File_Type: PNG Data_Set_Credit: 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. Native_Data_Set_Environment: Microsoft Windows 10; Agisoft Metashape Professional (version 1.6.6, build 11715); Adobe Photoshop (version 24.4) Cross_Reference: Citation_Information: Originator: Gerald A. Hatcher Originator: Jonathan A. Warrick Originator: Christine J. Kranenburg Originator: Andrew C. Ritchie Publication_Date: 20230726 Title: Accurate Maps of Reef-scale Bathymetry with Synchronized Underwater Cameras and GNSS Series_Information: Series_Name: Remote Sensing Issue_Identification: 15(15), 3727 Online_Linkage: https://doi.org/10.3390/rs15153727 Cross_Reference: Citation_Information: Originator: Gerald A. Hatcher Originator: Jonathan A. Warrick Originator: Andrew C. Ritchie Originator: Evan T. Dailey Originator: David G. Zawada Originator: Christine Kranenburg Originator: Kimberly K. Yates Publication_Date: 20200626 Title: Accurate Bathymetric Maps From Underwater Digital Imagery Without Ground Control Series_Information: Series_Name: Frontiers in Marine Science Issue_Identification: Volume 7, Article 525 Online_Linkage: https://doi.org/10.3389/fmars.2020.00525 Cross_Reference: Citation_Information: Originator: Codruta O. Ancuti Originator: Cosmin Ancuti Originator: Christophe De Vleeschouwer Originator: Philippe Bekaert Publication_Date: 2017 Title: Color Balance and Fusion for Underwater Image Enhancement Series_Information: Series_Name: IEEE Transactions on Image Processing Issue_Identification: Volume 27, Number 1 Online_Linkage: https://doi.org/10.1109/TIP.2017.2759252 Cross_Reference: Citation_Information: Originator: Jin-Si R. Over Originator: Andrew C. Ritchie Originator: Christine J. Kranenburg Originator: Jenna A. Brown Originator: Daniel Buscombe Originator: Tom Noble Originator: Christopher R. Sherwood Originator: Jonathan A. Warrick Originator: Philippe A. Wernette Publication_Date: 2021 Title: Processing Coastal Imagery with Agisoft Metashape Professional Edition, Version 1.6--Structure from Motion Workflow Documentation Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: 2021-1039 Online_Linkage: https://doi.org/10.3133/ofr20211039 Cross_Reference: Citation_Information: Originator: Gianfranco Bianco Originator: Maurizio Muzzupappa Originator: Fabio Bruno Originator: Rafael Garcia Originator: Laszlo Neumann Publication_Date: 20150409 Title: A New Color Correction Method for Underwater Imaging Series_Information: Series_Name: The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences Issue_Identification: Volume XL-5/W5, 25-32 Online_Linkage: https://doi.org/10.5194/isprsarchives-XL-5-W5-25-2015 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The accuracy of the position data used for SfM data processing is based on the accuracy and precision of the Global Navigation Satellite System (GNSS) equipment and camera timing. The post-processed GNSS navigation data produced a 10-hertz (Hz) vehicle trajectory with an estimated 2-sigma accuracy of 10 cm horizontal and 15 cm vertical. The horizontal accuracy of the orthoimages generated by SfM were assessed with positional error assessments of the cameras and found to be less than 5 cm. Logical_Consistency_Report: All data fall within expected ranges. Completeness_Report: Gaps in the data coverage are coded with a NoData value of -32,767 in the orthoimage. Gaps primarily occur either because the line spacing briefly widened such that there was insufficient sidelap for reconstruction, or over sand patches which have moving sandwaves and / or lack texture, which is necessary for image correlation. The largest of these data voids is an approximately 450 square meter void in the south-central section of the dataset. Additionally, small gaps may be present at vertical or concave surfaces due to the lack of visibility of these surfaces when viewed from above. These high-relief areas are common around the perimeter of reef spurs. No data were collected in 2 of the 10 potential tiles covered by the 5-by-2 index map. Data in those tiles were either too deep to be captured with an optical system or too shallow to access with the vessel used during data collection. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Previous SfM-based measurements of the field-based Sediment Elevation Table (SET) stations at USGS field sites in the Florida Keys were within 3 cm of the total uncertainty of the field-based GNSS measurements. Additionally, the average horizontal scaling of the models was found to be between 0.016 percent and 0.024 percent of water depth (Hatcher and others, 2020). No independent assessment of horizontal accuracy was possible from the Looe Key field site. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Christine J. Kranenburg Originator: Gerald A. Hatcher Originator: David G. Zawada Originator: Jonathan A. Warrick Originator: Kimberly K. Yates Publication_Date: 20231222 Title: Overlapping seabed images collected at Looe Key coral reef, Florida, 2022 Geospatial_Data_Presentation_Form: raster digital data Publication_Information: Publication_Place: St. Petersburg, Florida Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P9M3NYWI Online_Linkage: https://cmgds.marine.usgs.gov/data-services/rscc/SQUID/FL_2022_LooeKey/images/ Type_of_Source_Media: TIFF Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20220712 Ending_Date: 20220716 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: raw images Source_Contribution: Raw images to which SfM techniques were applied. Source_Information: Source_Citation: Citation_Information: Originator: Christine J. Kranenburg Originator: Gerald A. Hatcher Originator: David G. Zawada Originator: Jonathan A. Warrick Originator: Kimberly K. Yates Publication_Date: 20231222 Title: GNSS locations of seabed images collected at Looe Key coral reef, Florida, 2022 Geospatial_Data_Presentation_Form: tabular digital data Publication_Information: Publication_Place: St. Petersburg, Florida Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P9M3NYWI Online_Linkage: https://cmgds.marine.usgs.gov/data-services/rscc/SQUID/FL_2022_LooeKey/image_positions/FL_2022_LooeKey_Image_Locations.txt Type_of_Source_Media: comma-delimited text file Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20220712 Ending_Date: 20220716 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: GNSS antenna positions Source_Contribution: Location data for the raw images to which SfM techniques were applied. Process_Step: Process_Description: IMAGERY COLOR CORRECTION Because of the strong color modifications caused by light absorption and scattering in underwater imaging, a color correction process was conducted on the raw images. The color correction was a twofold process. First, images were corrected for the high absorption (and low color values) in the red band using the color balancing techniques of Ancuti and others (2017). For this, the red channel was modified using the color compensation equations of Ancuti and others (2017, see equation 4 on page 383) that use both image-wide and pixel-by-pixel comparisons of red brightness with respect to green brightness. After compensation, the images were white balanced using the "greyworld" assumption that is summarized in Ancuti and others (2017). Combined, these techniques ensured that each color band histogram was centered on similar values and had similar spread of values. The remaining techniques of Ancuti and others (2017), which include sharpening techniques and a multi-product fusion, were not employed. The resulting images utilized only about a quarter to a half of the complete 0-255 dynamic range of the three-color bands. Thus, the brightness values of each band were stretched linearly over the complete range while allowing the brightest and darkest 0.05 percent of the original image pixels (that is, 2506 of the 5.013 million pixels) to be excluded from the histogram stretch. This final element was included to ensure that light or dark spots in the images, which often occurred from water column particles or image noise, did not exert undo control on the final brightness values. Color-corrected images were output with the same file names and file types as the originals to make replacement within the SfM photogrammetry project easy. As a courtesy, the script used to implement this procedure is provided as a supplemental support file (OrthoImage_Color_Correction_Procedure.m), included in this related data release https://cmgds.marine.usgs.gov/data-releases/datarelease/10.5066-P93RIIG9/. Source_Used_Citation_Abbreviation: raw images Process_Date: 20221227 Source_Produced_Citation_Abbreviation: color-corrected images Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jonathan A. Warrick Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Position: Research Geologist Contact_Address: Address_Type: Physical and Mailing Address: 2885 Mission St. City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Country: USA Contact_Voice_Telephone: 831-460-7569 Contact_Electronic_Mail_Address: jwarrick@usgs.gov Process_Step: Process_Description: SfM PHOTOGRAMMETRY Digital imagery and position data recorded by the SQUID-5 system were processed using SfM photogrammetry techniques that generally follow the workflow outlined by Hatcher and others (2020 and 2023). These techniques are detailed here and include specific references to parameter settings and processing workflow. The primary software used for SfM processing was Agisoft Metashape Professional, version 1.6.6, build 11715, which will be referred to as "Metashape" in the discussion herein. Because of the large number of images in this dataset, processing was conducted on a 792-CPU-core linux-based High-Performance Computing (HPC) cluster at the USGS Advanced Research Computing (ARC) group (https://doi.org/10.5066/P9XE7ROJ). First, the raw images collected during the five mission days were added to a new project in Metashape. Raw images were used over the color-corrected images, owing to their larger dynamic range, which generally resulted in more SfM tie points. The images from each camera were assigned a unique camera calibration group in the Camera Calibration settings. Within the Camera Calibration settings, the camera parameters were also entered as 0.00345 x 0.00345 mm pixel sizes for all camera sensors, 8 mm focal length for the central camera (CAM13), and 6 mm focal lengths for the remaining cameras (CAM01, CAM39, CAM75, CAM82). These different focal lengths represented different lenses chosen for each camera. Additionally, the cameras required offsets to transform the GNSS positions to each camera's entrance pupil (that is, optical center). Initial measurements of these offsets were obtained using a separate SfM technique, outlined in Hatcher and others (2020), which found the offsets to be: Camera X(m) Y(m) Z(m) CAM01 -0.320 -0.205 0.823 CAM13 0.033 0.036 0.739 CAM39 0.170 -0.280 0.838 CAM75 0.047 0.396 0.698 CAM82 -0.110 -0.690 0.675 Where X and Y are the camera sensor parallel offsets, and Z is the sensor normal offset. The accuracy settings were chosen to be 0.01 m for CAM13 and 0.025 m for the other 4 cameras. Lastly, these offsets were allowed to be adjusted using the "Adjust GPS/INS offset" option, because slight camera shifts may occur with each rebuild and use of the SQUID-5 system. The SQUID-5 GNSS antenna positions were then imported into the project and matched with each image by time. The coordinates were converted in Metashape to the North American Datum of 1983 (NAD83 [2011]) Universal Transverse Mercator (UTM) Zone 17 North (17N) projected coordinate system, and altitudes were converted to the North American Vertical Datum of 1988 (NAVD88) orthometric heights (in meters). Prior to aligning the images, the Metashape reference settings were assigned. The coordinate system was "NAD83(2011) / UTM zone 17N". The camera accuracy was set to 0.10 m in the horizontal and 0.15 m in vertical dimensions, following an examination of the source GNSS data. Tie point accuracy was set at 1.0 pixels. The remaining reference settings were not relevant, because there were no camera orientation measurements, marker points, or scale bars in the SfM project. The data were then aligned in Metashape using the "Align Photos" workflow tool. Settings for the alignment included "High" accuracy, Generic preselection turned OFF and "Reference" preselection turned "ON" and using the "Source" information. This last setting allowed the camera position information to assist with the alignment process. Additionally, the key point limit was set to 50,000 and the tie point limit was assigned a value of zero, which allows for the generation of the maximum number of points for each image. Lastly, neither the "Guided image matching" nor the "Adaptive camera model fitting" options were used. This process resulted in over 205 million tie points. The total positional errors for the cameras were reported to be 0.042 m, 0.027 m, and 0.044 m in the east, north and altitude directions, respectively. Thus, the total positional error was 0.067 m. To improve upon the camera calibration parameters and computed camera positions, an optimization process was conducted that was consistent with the techniques of Hatcher and others (2020), which are based on the general principles provided in Over and others (2021). First, a duplicate of the aligned data was created in case the optimization process eliminated too much data using the "Duplicate Chunk" tool. Within the new chunk, the least valid tie points were removed using the "Gradual Selection" tools. As noted in Hatcher and others (2020), these tools are used less aggressively for the underwater imagery of SQUID-5 than commonly used for aerial imagery owing to the differences in image quality. First, all points with a "Reconstruction Uncertainty" greater than 20 were selected and deleted. Then, all points with a "Projection Accuracy" greater than 8 were selected and deleted. The camera parameters were then recalibrated with the "Optimize Cameras" tool. Throughout this process the only camera parameters that were adjusted were f, k1, k2, k3, cx, cy, p1, and p2. Once the camera parameters were adjusted, all points with "Reprojection Errors" greater than 0.4 were deleted, and the "Optimize Cameras" tool was used one final time. This optimization process resulted in slightly over 146.5 million tie points, a reduction of roughly 28 percent of the original tie points. The camera positional errors were reported to be 0.040 m, 0.025 m, and 0.044 m in the east, north and altitude directions, respectively, and the total positional error was 0.064 m. The final computed arm offsets were found to be: Camera X(m) Y(m) Z(m) CAM01 -0.317 -0.200 0.847 CAM13 0.019 -0.113 0.768 CAM39 0.168 -0.259 0.861 CAM75 0.049 0.417 0.717 CAM82 -0.108 -0.675 0.699 Following the alignment and optimization of the SQUID-5 data, mapped SfM products were generated in Metashape. For these steps, the original raw images were replaced with color-corrected images. This replacement was conducted by resetting each image path from the raw image to the color-corrected image. First, a three-dimensional dense point cloud was generated using the "Build Dense Cloud" workflow tool. This was run with the "High" quality setting and the "Moderate" depth filtering, and the tool was set to calculate both point colors and confidence. The resulting dense cloud was over 10.5 billion points over the 0.13 square kilometer survey area, or roughly 81,000 points per square meter (8.1 points per square centimeter). The dense points were classified by thresholding Metashape-computed confidence values, which are equivalent to the number of image depth maps that were integrated to make each point. Values of one were assigned "low noise", and values of two and greater were assigned "unclassified". The final Dense cloud was partitioned into blocks (also referred to as tiles) measuring 200 meters on a side and exported with point colors and classification as a LAZ file type. Source_Used_Citation_Abbreviation: raw images Source_Used_Citation_Abbreviation: color-corrected images Source_Used_Citation_Abbreviation: GNSS antenna positions Process_Date: 20230228 Source_Produced_Citation_Abbreviation: point cloud Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Christine J. Kranenburg Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Position: Cartographer Contact_Address: Address_Type: Physical and Mailing Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: ckranenburg@usgs.gov Process_Step: Process_Description: GENERATION OF DIGITAL ELEVATION MODEL (DEM) A digital elevation model (DEM), which is a x,y raster of elevation values, was generated from the point cloud using the Metashape "Build DEM" workflow tool using a geographic projection, dense cloud source data, interpolation disabled, and the default output resolution of 0.00511 meters. Source_Used_Citation_Abbreviation: point cloud Process_Date: 20230228 Source_Produced_Citation_Abbreviation: DEM Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Christine J. Kranenburg Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Position: Cartographer Contact_Address: Address_Type: Physical and Mailing Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: ckranenburg@usgs.gov Process_Step: Process_Description: DEHAZING First, local contrast and hue were adjusted in the Ruderman opponent color space by white-balancing chromatic components using the techniques of Bianco and others (2015). This was followed by color correction using the color balancing techniques of Ancuti and others (2017). A final step to reduce haze and shadows in the images was performed in Adobe Photoshop by creating a custom action with a neighborhood Shadow/Highlight adjustment and Camera Raw filter that adjusts the tonal width and intensity of shadows, midtones, and highlights. Photoshop adjustment parameters for CAM01 and CAM75 were set as follows: Shadow/Highlight adjustment parameters were set as follows: Shadow Amount 35%, Shadow Tone Width 50%, Shadow Radius 50px, Shadow Highlight Amount 10%, Highlight Tone Width 50%, Highlight Radius 50px, Midtone Contrast 35, Midtone Color 20. Camera Raw filter parameters were set as follows: Exposure +0.15, Contrast +10, Highlights -10, Shadows, +10, Dehaze +10, Clarity +5, Saturation Adjust Magenta -100. Photoshop adjustment parameters for CAM13 were set as follows: Shadow/Highlight adjustment parameters were set as follows: Shadow Amount 35%, Shadow Tone Width 50%, Shadow Radius 50px, Shadow Highlight Amount 10%, Highlight Tone Width 50%, Highlight Radius 50px, Midtone Contrast 30, Midtone Color 20. Camera Raw filter parameters were set as follows: Exposure +0.05, Contrast +20, Highlights -10, Shadows, +10, Dehaze +10, Clarity +10, Saturation Adjust Magenta -100. Photoshop adjustment parameters for CAM39 and CAM 82 were set as follows: No Shadow/Highlight adjustment applied. Camera Raw filter parameters were set as follows: Contrast +20, Highlights -10, Shadows, +10, Whites -20, Blacks -20, Dehaze +15, Clarity +10, Saturation Adjust Magenta -100. The resulting dehazed images were not used for point cloud or DEM creation--they were used solely for creating a sharper, more color-rich orthoimage. Dehazed images were output with the same file names and file types as the originals to make replacement within the SfM photogrammetry project simple. Source_Used_Citation_Abbreviation: raw images Process_Date: 20230621 Source_Produced_Citation_Abbreviation: dehazed images Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Selena A. Johnson Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Position: Research Physical Scientist Contact_Address: Address_Type: Physical and Mailing Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: selenajohnson@usgs.gov Process_Step: Process_Description: ORTHOIMAGERY GENERATION Before building the orthoimage, the color-corrected images were replaced with dehazed images. This replacement was conducted by resetting each image path from the color-corrected images to the dehazed images. An orthomosaic image product was then made using the Metashape "Build Orthomosaic" workflow tool using the interpolated DEM surface as the base and "Average" blending mode. Hole-filling was disabled and seamlines were not refined. An output pixel size of 0.005 m was used in generating the orthoimage product. The resulting orthoaverage GeoTIFF rasters are available in a 5-mm resolution, as a 5-by-2 tile index grid (8 tiles total, due to 2 tiles containing no data). A "quicklook" version of this orthoimage was also created by exporting the data at a 25-cm pixel resolution. The orthoimages were then converted to a Cloud Optimized GeoTIFF (COG) format using the Geospatial Data Abstraction Library (GDAL). For more information on COGs see the USGS website: https://www.usgs.gov/faqs/what-are-cloud-optimized-geotiffs-cogs Source_Used_Citation_Abbreviation: DEM Source_Used_Citation_Abbreviation: dehazed images Process_Date: 20240328 Source_Produced_Citation_Abbreviation: orthoaverage images Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Christine J. Kranenburg Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Position: Cartographer Contact_Address: Address_Type: Physical and Mailing Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: ckranenburg@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 17N Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -81 Latitude_of_Projection_Origin: 0.0 False_Easting: 500000.0 False_Northing: 0.0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.005 Ordinate_Resolution: 0.005 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 (2011) Ellipsoid_Name: GRS 1980 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257222101 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: The orthoimages are presented as tiled 4-band (R, G, B plus Alpha) 8-bit unsigned integer GeoTIFFs where pixels represent RGB color from the dehazed images and no-data is represented as 0 in the alpha band. The horizontal projection is NAD83(2011) UTM Zone 17N. These orthoaverage GeoTIFFs are available in 5-mm resolution for eight blocks (or tiles) of the survey area. Each tile measures 200 meters on a side and are labeled SQUID5_LKR_2022_Orthoaverage-col-row.tif where col represents the column name and can have a value of A-E, and row is the row number and can have a value of 0-1. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Address: Address_Type: Mailing and Physical Address: 600 4th St. South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: gs-g-spcmsc_data_inquiries@usgs.gov Resource_Description: SQUID5_LKR_2022_Orthoaverage-col-row.tif* Distribution_Liability: 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. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: TIFF Format_Information_Content: TIFF images can be opened directly with any TIFF-compatible image viewer. File_Decompression_Technique: Adobe Deflate Transfer_Size: 9801 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P1QRS3SK Access_Instructions: The 5-mm resolution orthoaverage GeoTIFF tiles and the 25-cm resolution "quicklook" orthoimage GeoTIFF can be downloaded by going to the Network_Resource_Name link and scrolling down to the Imagery Data section. For the 5-mm resolution GeoTIFFs, the file names correspond to the 5-by-2 tile index grid shown in the location map and are named according to the following convention: SQUID5_LKR_2022_Orthoaverage-col-row.tif, where col represents the column name and can have a value of A-E, and row represents the row number and can have a value of 0-1. Note that 2 of the possible 10 tiles are empty, resulting in 8 orthoimagery data files. Fees: None Metadata_Reference_Information: Metadata_Date: 20240814 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Person: SPCMSC Data Management Group Contact_Address: Address_Type: mailing and physical Address: 600 4th St. South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: gs-g-spcmsc_data_inquiries@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998