Multispectral aerial imagery collected during uncrewed aircraft systems (UAS) operations: Plum Island Estuary and Parker River NWR (PIEPR), Massachusetts, November 14, 2017 and March 28, 2019

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Frequently anticipated questions:

What does this data set describe?

Title:
Multispectral aerial imagery collected during uncrewed aircraft systems (UAS) operations: Plum Island Estuary and Parker River NWR (PIEPR), Massachusetts, November 14, 2017 and March 28, 2019
Abstract:
Low-altitude (80 and 100 meters above ground level) digital images were collected by the USGS Woods Hole Coastal and Marine Science Center (WHCMSC) Aerial Imaging and Mapping Group (AIMG) over an area of the Plum Island Estuary and Parker River National Wildlife Refuge (NWR) in Massachusetts on November 14, 2017 and March 28, 2019 to document marsh stability over time and quantify sediment movement. A 3DR Solo uncrewed aircraft systems (UAS) was equipped with either a Ricoh GR II digital camera for true color photos, which can be used to produce digital elevation models and ortho images, or a MicaSense RedEdge multispectral camera for five-banded imagery (blue, green, red, red edge, and near-infrared spectral bands), which can be used to classify vegetation. The MicaSense camera covered a smaller subsection of the same polygonal area of the marsh that the Ricoh imaged. Some photographs contain black and white targets used as ground control points (GCPs), which were surveyed by a field crew with a high-precision Real-Time Kinematic Global Positioning System. This data release includes the original images from both cameras, as well as a CSV file containing the latitude and longitude coordinates, in Universal Transverse Mercator Zone 19N referenced to the North American Datum of 1983, of the ground control points needed to complete any photogrammetry projects using the original photographs, and GPS transect points used to evaluate the photogrammetry products created.
Supplemental_Information:
These data were collected by the U.S. Geological Survey (USGS) Coastal and Marine Hazards and Resources Program (CMHRP) during USGS field activities 2017-057-FA and 2019-009-FA. For more information about these field activities, see the field activity webpages at https://cmgds.marine.usgs.gov/fan_info.php?fan=2017-057-FA and https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-009-FA.
  1. How might this data set be cited?
    U.S. Geological Survey, 20221222, Multispectral aerial imagery collected during uncrewed aircraft systems (UAS) operations: Plum Island Estuary and Parker River NWR (PIEPR), Massachusetts, November 14, 2017 and March 28, 2019: data release DOI:10.5066/P9PP35F4, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts.

    Online Links:

    This is part of the following larger work.

    Cramer, Jennifer M., Huntley, Emily C., Brosnahan, Sandra M., Ganju, Neil K., Sturdivant, Emily J., Pendleton, Elizabeth A., Ackerman, Seth D., and Borden, Jonathan, 2022, Aerial imagery and ground control points collected during an uncrewed aerial systems (UAS) survey at Plum Island Estuary and Parker River NWR (PIEPR), November 14, 2017 and March 28, 2019: data release DOI:10.5066/P9PP35F4, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Cramer, J.M., Huntley, E.C., Brosnahan, S.M., Ganju, N.K., Sturdivant, E.J., Pendleton, E.A., Ackerman, S.D., and Borden, J., 2022, Aerial imagery and ground control points collected during an uncrewed aerial systems (UAS) survey at Plum Island Estuary and Parker River NWR (PIEPR), November 14, 2017 and March 28, 2019: U.S. Geological Survey data release, https://doi.org/10.5066/P9PP35F4.
  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -70.816458
    East_Bounding_Coordinate: -70.805353
    North_Bounding_Coordinate: 42.776738
    South_Bounding_Coordinate: 42.771010
  3. What does it look like?
    https://www.sciencebase.gov/catalog/file/get/62a62a1dd34ec53d2770c25d?name=2017057FA_2019009FA_multispectral_imagery_browse.jpg (JPEG)
    Example near-infrared band image of Plum Island, Massachusetts, taken in March 2019.
  4. Does the data set describe conditions during a particular time period?
    Calendar_Date: 14-Nov-2017
    Currentness_Reference:
    ground condition
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: remote-sensing image
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Raster data set.
    2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is D_WGS_1984.
      The ellipsoid used is WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257224.
      Vertical_Coordinate_System_Definition:
      Altitude_System_Definition:
      Altitude_Datum_Name: IGS08 (EPOCH:2017.8707)
      Altitude_Resolution: 0.01
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method: Attribute values
  7. How does the data set describe geographic features?
    2017057FA_2019009FA_multispectral_imageryNav.csv
    CSV file containing navigation information for the MicaSense images from the USGS field activities 2017-057-FA and 2019-009-FA. (Source: U.S. Geological Survey)
    GPSDateStamp
    UTC date of the photo acquisition in the format YYYY:MM:DD where YYYY is the year, MM is the month, and DD is the day of the month. (Source: U.S. Geological Survey) Text field
    GPSTimeStamp
    UTC time of the photo acquisition in the format HH:MM:SS where HH is hour, MM is minute, and SS is seconds. (Source: U.S. Geological Survey) Text field
    GPSLatitude
    Latitude of the camera location at time of photo acquisition with the positive value indicating northern hemisphere. (Source: U.S. Geological Survey)
    Range of values
    Minimum:42.7710101
    Maximum:42.7767379
    Units:decimal degrees
    GPSLongitude
    Longitude of the camera location at time of photo acquisition with the negative value indicating western hemisphere. (Source: U.S. Geological Survey)
    Range of values
    Minimum:-70.8164578
    Maximum:-70.8053532
    Units:decimal degrees
    Filename
    Image name in the USGS format. An example filename and the convention is: 2017057FA_m01f02_20171114T155121Z_IMG_0015_5.tif, where 2017057FA refers to the field activity, m01 refers to the camera (MicaSense sensor 1), f02 refers to the flight number, 20171114T155121Z refers to the image date and time in the ISO 8601 standard (YYYYMMDD T [time separator] HHMMSS Z [Zulu/UTC time]), and IMG_0015_5 refers to the original filename assigned to the image by the camera. (Source: U.S. Geological Survey) Text field
    Entity_and_Attribute_Overview:
    As an alternative to using the CSV file, the complete metadata embedded in the header of each image can be extracted or viewed to get additional information about each image. Process step 5 above explains how to extract the information from the image headers and is replicated here.
    To extract the geotagging and survey information (except for the duplicated tags) from the image metadata using ExifTool, the following command can be used (tested with ExifTool version 11.86):
    exiftool -csv -filename -EXIF:GPSTimeStamp -EXIF:GPSDateStamp -GPSLatitude -GPSLongitude -n -IPTC:Credit -IPTC:Contact -EXIF:Copyright -XMP:UsageTerms -EXIF:ImageDescription -XMP:AttributionURL -EXIF:GPSAreaInformation -EXIF:GPSMapDatum -EXIF:Artist -ext tif . > out.csv
    The "-csv" option writes the information to a CSV file. The "-n" option formats the latitude and longitude as signed decimal degrees. Please note that the above command was tested on macOS; Windows users may need to use "exiftool.exe" instead of "exiftool."
    Entity_and_Attribute_Detail_Citation: U.S. Geological Survey

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • U.S. Geological Survey
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
    U.S. Geological Survey, Woods Hole Coastal and Marine Science Center
    Attn: Sandra Brosnahan
    Physical Scientist
    384 Woods Hole Road
    Woods Hole, MA
    USA

    508-548-8700 x2265 (voice)
    508-457-2310 (FAX)
    sbrosnahan@usgs.gov

Why was the data set created?

These multispectral images were collected with the appropriate resolution and overlap to permit high-quality photogrammetry and generation of reflectance imagery and multispectral indices.

How was the data set created?

  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
    Date: 2019 (process 1 of 7)
    Step 1: Set up equipment.
    A MicaSense RedEdge multispectral camera was mounted on a 3DR Solo Quadcopter UAS. The MicaSense RedEdge acquires images at 1.2 megapixels with image dimensions of 1280 X 960 pixels in 12-bit DNG format. The lens focal length is 5.5 mm, and the camera has global shutters for all five bands (blue, green, red, red edge, and near infrared) with an aperture of f2.8. File sizes are generally 1.8 MB on disc. The camera is generally down-looking, so the imaged area was dependent on the tilt of the quadcopter during flight. For flight, the camera was set to record images at 2-second intervals, activated before takeoff and deactivated after landing.
    A 3DR GPS module and MicaSense Downwelling Light Sensor were connected to the camera with 6-pin cables and secured on top of the aircraft with velcro. The camera received power from a connection to the UAS. The 3DR GPS module was a pre-configured u-blox NEO-7 that used a 25 x 25 x 4 mm ceramic patch antenna with a 5 Hz update rate. It recorded telemetry information including latitude, longitude, altitude, dilution of precision, date and time, roll, pitch, and yaw. The downwelling light sensor measured ambient light for each of the five spectral bands captured by the camera. For each camera shutter trigger, it recorded spectral data including spectral irradiance, roll, pitch, yaw, gain, and exposure time. Data from the downwelling light sensor and GPS module were automatically incorporated into the metadata embedded in the header of each image. Person who carried out this activity:
    U.S. Geological Survey, Woods Hole Coastal and Marine Science Center
    Attn: Sandra Brosnahan
    Physical Scientist
    384 Woods Hole Road
    Woods Hole, MA
    USA

    508-548-8700 x2265 (voice)
    508-457-2310 (FAX)
    sbrosnahan@usgs.gov
    Date: 2019 (process 2 of 7)
    Step 2: Collected images.
    The images were collected during field activity 2017-057-FA on November 14, 2017, and field activity 2019-009-FA on March 28, 2019. During each field activity, flights were flown approximately 80 meters above ground level along pre-planned lines and lasted the duration of the UAS battery life (approximately 15 minutes) or until the flight was completed or aborted. During a flight, five images were captured every 2 seconds, one for each of the five wavelengths (blue [475 nm], green [560 nm], red [668 nm], red edge [717 nm], and near infrared [840 nm]). The ending number of the image filenames corresponds to the band number: _1 corresponds to blue, _2 corresponds to green, _3 corresponds to red, _4 corresponds to near infrared, and _5 corresponds to red edge. After a flight, the SD card was removed from the camera, and all files related to the flight were downloaded and organized by flight number.
    At the start of the field activity and throughout the day, calibration images were taken of a MicaSense Calibrated Reflectance Panel by manually triggering the camera shutter with the UAS held over the panel. Before the images can be used to create photogrammetry products, they need to be radiometrically calibrated to account for changing light conditions during flight. The standardized reflectance values provided by MicaSense for this panel are 0.61 for near infrared, 0.63 for blue, and 0.64 for green, red, and red edge. Calibration images should be chosen to temporally match the UAS images as closely as possible. Person who carried out this activity:
    Sandra Brosnahan
    U.S. Geological Survey
    Physical Scientist
    384 Woods Hole Road
    Woods Hole, MA
    USA

    508-548-8700 x2265 (voice)
    508-457-2310 (FAX)
    sbrosnahan@usgs.gov
    Date: 19-Apr-2019 (process 3 of 7)
    Step 3: Renamed the 2019 images and incorporated survey information into the 2019 images' metadata.
    A Python script (image_RenameTagFilter.py) was run to rename the 2019 images and incorporate standard USGS tags and additional survey information into the 2019 images using ExifTool by Phil Harvey. The images were renamed to append the field activity ID, camera ID, flight ID, and UTC date and time to the beginning of each filename. For example, IMG_0003_1.tif was renamed to 2019009FA_m01f01_20190328T155433Z_IMG_0003_1.tif where 2019009FA refers to the field activity, m01 refers to the camera (MicaSense sensor 1), f01 refers to the flight number, 20190328T155433Z refers to the image date and time in the ISO 8601 standard (YYYYMMDD T [time separator] HHMMSS Z [Zulu/UTC time]), and IMG_0003_1 refers to the original filename assigned to the image by the camera.
    The Python script also incorporated standard USGS tags into the metadata embedded in the header of each image using ExifTool. Images may have different metadata formats embedded in their headers, and the script incorporated survey information into the following three image metadata formats: Exchangeable image file format (Exif), International Press Telecommunications Council (IPTC), and Extensible Metadata Platform (XMP). The standard USGS tags at the time have since changed and were subsequently updated in a process step below. The following tags were populated and were not subsequently updated because they are no longer part of the standard USGS tags. Please note that the Exif UserComment tag was populated for all the 2019 images, while the remaining IPTC and XMP tags were only populated in the calibration images collected at the start of the 2019 survey and in the images collected during flight 6.
    Exif tag and the information used to populate the tag (for all 2019 images):
    UserComment (for calibration images): Flight CAL UserComment (for images collected during flights): Flight [ID] ; target altitude 80 m
    IPTC tags and the information used to populate the tags (for 2019 calibration and flight 6 images):
    Caption-Abstract: One band of a multispectral image from a low-altitude aerial survey in Plum Island, MA. Captured with a MicaSense RedEdge at a target altitude of 80 m. WHCMSC field activity number 2019-009-FA (https://cmgds.marine.usgs.gov/fan_info.php?fa=2019-009-FA). CopyrightNotice: Public Domain. Please credit U.S. Geological Survey Keywords: Plum Island, MA, Massachusetts, 2019-009-FA, UAS, nadir, multispectral, USGS
    XMP tag and the information used to populate the tag (for 2019 calibration and flight 6 images):
    Caption: One band of a multispectral image from a low-altitude aerial survey in Plum Island, MA. Captured with a MicaSense RedEdge at a target altitude of 80 m. WHCMSC field activity number 2019-009-FA (https://cmgds.marine.usgs.gov/fan_info.php?fa=2019-009-FA). Person who carried out this activity:
    Emily Sturdivant
    U.S. Geological Survey
    Geographer
    384 Woods Hole Road
    Woods Hole, MA
    USA

    508-548-8700 (voice)
    508-457-2310 (FAX)
    Date: 22-May-2022 (process 4 of 7)
    Step 4: Renamed the 2017 images.
    The images collected during the 2017 survey were renamed to append the field activity ID, camera ID, flight ID, and UTC date and time to the beginning of each filename. The MicaSense camera recorded the GPS date and time from the GPS connected to the camera to the Exif CreateDate tag. Before renaming the images, the Exif CreateDate tag was copied to the Exif GPSDateStamp and GPSTimeStamp tags using the following ExifTool (version 11.86) command:
    exiftool -P "-GPSTimeStamp<CreateDate" "-GPSDateStamp<CreateDate" -overwrite_original *.tif
    To rename the images, a command was run on each flight's images to extract the GPS date and time using ExifTool and format them into the new filename. For example, the following command was used on the images collected during flight 2:
    exiftool -csv *.tif -GPSTimeStamp -GPSDateStamp | awk -F, '{split($1,a,"_"); split($2,t,":"); split($3,d,":");print "mv -v "$1" 2017057FA_m01f02_"d[1]d[2]d[3]"T"t[1]t[2]t[3]"Z_"$1}' | sh
    An example renamed filename for the 2017 images is 2017057FA_m01f02_20171114T155121Z_IMG_0015_1.tif where 2017057FA refers to the field activity, m01 refers to the camera (MicaSense sensor 1), f02 refers to the flight number, 20171114T155121Z refers to the image date and time in the ISO 8601 standard (YYYYMMDD T [time separator] HHMMSS Z [Zulu/UTC time]), and IMG_0015_1 refers to the original filename assigned to the image by the camera. Person who carried out this activity:
    Emily Huntley
    U.S. Geological Survey
    Geographer/Database Specialist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 (voice)
    508-457-2310 (FAX)
    ehuntley@contractor.usgs.gov
    Date: 10-Jun-2022 (process 5 of 7)
    Step 5: Incorporated survey information into the images' metadata.
    The updated standard USGS tags were incorporated into the metadata embedded in the header of each image using several commands. As previously mentioned, the MicaSense camera recorded the GPS date and time from the GPS connected to the camera to the Exif CreateDate tag. First, the Exif CreateDate tag was copied to the Exif GPSDateStamp and GPSTimeStamp tags for the 2019 images using the following ExifTool (version 11.86) command:
    exiftool -P "-GPSTimeStamp<CreateDate" "-GPSDateStamp<CreateDate" -overwrite_original *.tif
    Next, the following ExifTool command was run to incorporate standard USGS tags and survey information into the metadata embedded in the headers of the 2017 images:
    exiftool -P "-XMP:PreservedFileName<Filename" -IPTC:Credit="U.S. Geological Survey" -IPTC:Contact="WHSC_data_contact@usgs.gov" -EXIF:Copyright="Public Domain" -XMP:UsageTerms="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 for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty." -EXIF:ImageDescription="https://cmgds.marine.usgs.gov/fan_info.php?fan=2017-057-FA; One band of a multispectral image from a low-altitude aerial survey in Plum Island, Massachusetts, from USGS field activity 2017-057-FA" -XMP:AttributionURL="https://doi.org/10.5066/P9PP35F4" -EXIF:GPSAreaInformation="position derived from UAS GPS" -EXIF:GPSMapDatum="EPSG:7660 (WGS 84 [G1150])" -EXIF:Artist="Woods Hole Coastal and Marine Science Center (WHCMSC) Aerial Imaging and Mapping (AIM) Group" -overwrite_original -ext tif .
    Then, the following ExifTool command was run to incorporate standard USGS tags and survey information into the metadata embedded in the headers of the 2019 images:
    exiftool -P "-XMP:PreservedFileName<Filename" -IPTC:Credit="U.S. Geological Survey" -IPTC:Contact="WHSC_data_contact@usgs.gov" -EXIF:Copyright="Public Domain" -XMP:UsageTerms="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 for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty." -EXIF:ImageDescription="https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-009-FA; One band of a multispectral image from a low-altitude aerial survey in Plum Island, Massachusetts, from USGS field activity 2019-009-FA" -XMP:AttributionURL="https://doi.org/10.5066/P9PP35F4" -EXIF:GPSAreaInformation="position derived from UAS GPS" -EXIF:GPSMapDatum="EPSG:7660 (WGS 84 [G1150])" -EXIF:Artist="Woods Hole Coastal and Marine Science Center (WHCMSC) Aerial Imaging and Mapping (AIM) Group" -overwrite_original -ext tif .
    Finally, the following ExifTool command was run on both the 2017 and 2019 images to duplicate values from Exif and IPTC metadata tags to XMP tags because various software packages read different tags:
    exiftool -P "-XMP-photoshop:Credit<IPTC:Credit" "-XMP-iptcCore:CreatorWorkEmail<IPTC:Contact" "-XMP-dc:Rights<EXIF:Copyright" "-XMP-dc:Description<EXIF:ImageDescription" "-XMP-exif:all<GPS:all" "-XMP-exif:GPSLatitude<Composite:GPSLatitude" "-XMP-exif:GPSLongitude<Composite:GPSLongitude" "-XMP-exif:GPSDateTime<Composite:GPSDateTime" "-XMP-photoshop:DateCreated<EXIF:DateTimeOriginal" "-XMP-xmp:ModifyDate<EXIF:ModifyDate" "-XMP-dc:Creator<EXIF:Artist" "-XMP-tiff:Make<EXIF:Make" "-XMP-tiff:Model<EXIF:Model" -overwrite_original .
    The following metadata tags were populated in the image headers using the above ExifTool commands. Please note that only a subset of these tags may be accessed depending on the software used to view the image metadata.
    Exif tags and the information used to populate these tags:
    Artist: Woods Hole Coastal and Marine Science Center (WHCMSC) Aerial Imaging and Mapping (AIM) Group Copyright: Public Domain GPSAreaInformation: position derived from UAS GPS GPSDateStamp (2019 images): duplicated from Exif CreateDate GPSMapDatum: EPSG:7660 (WGS 84 [G1150]) GPSTimeStamp (2019 images): duplicated from Exif CreateDate ImageDescription (2017 images): https://cmgds.marine.usgs.gov/fan_info.php?fan=2017-057-FA; One band of a multispectral image from a low-altitude aerial survey in Plum Island, Massachusetts, from USGS field activity 2017-057-FA ImageDescription (2019 images): https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-009-FA; One band of a multispectral image from a low-altitude aerial survey in Plum Island, Massachusetts, from USGS field activity 2019-009-FA
    IPTC tags and the information used to populate these tags:
    Contact: WHSC_data_contact@usgs.gov Credit: U.S. Geological Survey
    XMP tags and the information used to populate these tags:
    AttributionURL: https://doi.org/10.5066/P9PP35F4 Creator: duplicated from Exif Artist CreatorWorkEmail: duplicated from IPTC Contact Credit: duplicated from IPTC Credit DateCreated: duplicated from Exif DateTimeOriginal Description: duplicated from Exif ImageDescription GPSAreaInformation: duplicated from Exif GPSAreaInformation by copying all the Exif GPS tags to the same-named tags in XMP (-XMP-exif:all<GPS:all) GPSDateTime: duplicated using the composite of Exif GPSDateStamp and Exif GPSTimeStamp GPSLatitude: duplicated using the composite of Exif GPSLatitude and Exif GPSLatitudeRef GPSLongitude: duplicated using the composite of Exif GPSLongitude and Exif GPSLongitudeRef GPSMapDatum: duplicated from Exif GPSMapDatum by copying all the Exif GPS tags to the same-named tags in XMP (-XMP-exif:all<GPS:all) Make: duplicated from Exif Make Model: duplicated from Exif Model ModifyDate: duplicated from Exif ModifyDate PreservedFileName: original image file name, which is unique for each image Rights: duplicated from Exif Copyright UsageTerms: 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 for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty.
    To extract the geotagging and survey information (except for the duplicated tags) from the image metadata using ExifTool, the following command can be used (tested with ExifTool version 11.86):
    exiftool -csv -filename -EXIF:GPSTimeStamp -EXIF:GPSDateStamp -GPSLatitude -GPSLongitude -n -IPTC:Credit -IPTC:Contact -EXIF:Copyright -XMP:UsageTerms -EXIF:ImageDescription -XMP:AttributionURL -EXIF:GPSAreaInformation -EXIF:GPSMapDatum -EXIF:Artist -ext tif . > out.csv
    The "-csv" option writes the information to a CSV file. The "-n" option formats the latitude and longitude as signed decimal degrees. Please note that the above command was tested on macOS; Windows users may need to use "exiftool.exe" instead of "exiftool." Person who carried out this activity:
    Emily Huntley
    U.S. Geological Survey
    Geographer/Database Specialist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 (voice)
    508-457-2310 (FAX)
    ehuntley@contractor.usgs.gov
    Date: 11-Jun-2022 (process 6 of 7)
    Step 6: Added the missing coordinates for the calibration images collected in 2019 during flights 4 and 6.
    During the 2019 survey, the calibration images collected at the start of flights 4 and 6 (2019009FA_m01CAL_20190328T170520Z_IMG_0000_* and 2019009FA_m01CAL_20190328T184445Z_IMG_0000_*) were missing coordinates, so the coordinates from the first calibration image taken at the start of the survey (2019009FA_m01CAL_20190328T155036Z_IMG_0000_1.tif) were used to populate these missing coordinates. The following ExifTool (version 11.86) command was run to populate the missing coordinates in the calibration images:
    exiftool -TagsFromFile 2019009FA_m01CAL_20190328T155036Z_IMG_0000_1.tif "-EXIF:GPSLatitude<EXIF:GPSLatitude" "-EXIF:GPSLatitudeRef<EXIF:GPSLatitudeRef" "-EXIF:GPSLongitude<EXIF:GPSLongitude" "-EXIF:GPSLongitudeRef<EXIF:GPSLongitudeRef" -overwrite_original -P -ext tif . Person who carried out this activity:
    Emily Huntley
    U.S. Geological Survey
    Geographer/Database Specialist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 (voice)
    508-457-2310 (FAX)
    ehuntley@contractor.usgs.gov
    Date: 14-Dec-2022 (process 7 of 7)
    Step 6: Create image location CSV file.
    The image details were downloaded for the entire set of photos on this data release from the CMHRP Imagery Data System, providing the exif_data.csv file. The file was parsed for records that contain navigation data for the MicaSense camera. The columns containing the date, time, latitude, longitude and image filename were kept, the rest of the columns were deleted, resulting in a simplified CSV image location file. The file header line was edited to give each column names as described in the attribute information in this metadata file. Person who carried out this activity:
    Seth Ackerman
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd.
    Woods Hole, MA
    USA

    508-548-8700 x2315 (voice)
    508-457-2310 (FAX)
    sackerman@usgs.gov
  3. What similar or related data should the user be aware of?
    Ganju, Neil K., Brosnahan, Sandra M., Sturdivant, Emily J., Pendleton, Elizabeth A., and Ackerman, Seth D., 20190529, Aerial imagery from unmanned aerial systems (UAS) flights and ground control points-Plum Island Estuary and Parker River NWR (PIEPR), February 27th, 2018: U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    This publication represents data collected in the same way and in the same place in 2018

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    The GPS used on the UAS has theoretical accuracies of 3 meters horizontally and 10 meters vertically. The location values are stored in the metadata embedded in the header of each image. Two multispectral images (2019009FA_m01f03_20190328T165938Z_IMG_0294_* and 2019009FA_m01f03_20190328T165938Z_IMG_0295_*) have the same timestamp, but the second image (2019009FA_m01f03_20190328T165938Z_IMG_0295_*) was likely collected two seconds later.
  2. How accurate are the geographic locations?
    Horizontal positions recorded in the metadata embedded in the header of each image were derived from a 3DR u-blox NEO-7 GPS, which receives signals from GPS and GLONASS satellites in WGS 84 (G1150) EPSG:7660 but is otherwise uncorrected. Horizontal locations are considered accurate to approximately 3 meters, but they may have inaccuracies greater than 10 meters due to the UAS flight path and uncertainty associated with the geotagging process. During the 2019 survey, the calibration images taken at the start of flights 4 and 6 (2019009FA_m01CAL_20190328T170520Z_IMG_0000_* and 2019009FA_m01CAL_20190328T184445Z_IMG_0000_*) were missing coordinates, so the coordinates from the first calibration image taken at the start of the survey (2019009FA_m01CAL_20190328T155036Z_IMG_0000_1.tif) were used to populate these missing coordinates.
  3. How accurate are the heights or depths?
    Vertical positions were recorded in the metadata embedded in the header of each image. Vertical positions are ellipsoidal heights derived from a 3DR u-blox NEO-7 GPS, which receives signals from GPS and GLONASS satellites but is otherwise uncorrected. Vertical locations are less accurate than horizontal positions with inaccuracies greater than 10 meters.
  4. Where are the gaps in the data? What is missing?
    This dataset includes geotagged images in TIFF format collected with a multispectral camera during field activities 2017-057-FA and 2019-009-FA. A total of 19 flights (13 flights in 2017, two of which were test flights, and six flights in 2019) were conducted with the multispectral camera over the two surveys. Five images were captured every 2 seconds, one for each different wavelength (blue, green, red, red edge, and near infrared). During the 2019 survey, the camera would sometimes temporarily stop collecting images during a flight, so there may be time gaps up to 55 seconds between sequential images. For the 2017 images, images of the launch pad at the beginning and end of the flights, as well as the images collected during the two test flights (flights 1 and 6), were removed from this dataset. Radiometric calibration images are included for post-processing purposes. A total of 20,525 images collected over the two surveys (12,430 in 2017 and 8,095 in 2019) are included in this dataset.
  5. How consistent are the relationships among the observations, including topology?
    The metadata embedded in the image file headers was modified to incorporate standard USGS tags and additional survey information. The images were renamed to append the field activity ID, camera ID, flight ID, and date and time in Coordinated Universal Time (UTC) to the beginning of each filename. The MicaSense camera stores images in folders of 200 multispectral images; if more than 200 multispectral images were captured during a flight, then the camera would restart the file numbers in a new folder. A flight may therefore have multiple images with the same original filename (e.g., flight 5 in 2017 has two images with an original filename of IMG_0026_1.tif). Five images were captured every 2 seconds, one for each different wavelength (blue, green, red, red edge, and near infrared). Each image is a single wavelength and will appear grayscale when viewed independently. During the 2019 survey, the camera would sometimes temporarily stop collecting images during a flight, so there may be time gaps up to 55 seconds between sequential images. During the 2017 survey, flights 1 and 6 were test flights, so the images collected during these flights are not included in this data release. Ground control point (GCP) targets are visible in some of the images; for more information about GCPs, see the ground control metadata available from the larger work citation.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints None
Use_Constraints Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey - ScienceBase
    Denver Federal Center, Building 810, Mail Stop 302
    Denver, CO
    USA

    1-888-275-8747 (voice)
    sciencebase@usgs.gov
  2. What's the catalog number I need to order this data set? This dataset includes geotagged multispectral aerial images and calibration images in TIFF format collected during UAS operations over Plum Island Estuary and Parker River National Wildlife Refuge, Massachusetts, on November 14, 2017, and March 28, 2019, by the U.S. Geological Survey during field activities 2017-057-FA and 2019-009-FA. This dataset contains the following files: 20,525 geotagged images collected over the two surveys (12,430 in 2017 and 8,095 in 2019), a CSV file with the location of each image (2017057FA_2019009FA_multispectral_imageryNav.csv), a browse graphic of an example near-infrared band image (2017057FA_2019009FA_multispectral_imagery_browse.jpg), and a Federal Geographic Data Committee (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM) metadata file (2017057FA_2019009FA_multispectral_imagery.xml). The images themselves are distributed through the Imagery Data System and are available through the Network Resource Name link below, while the browse graphic and metadata file are available through ScienceBase.
  3. What legal disclaimers am I supposed to read?
    Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
  4. How can I download or order the data?
  5. What hardware or software do I need in order to use the data set?
    These files require software capable of opening TIFF images and, if desired, capable of viewing metadata embedded in the headers of the images.

Who wrote the metadata?

Dates:
Last modified: 22-Dec-2022
Metadata author:
Emily Huntley
U.S. Geological Survey, Woods Hole Coastal and Marine Science Center
Geographer/Database Specialist
384 Woods Hole Rd.
Woods Hole, MA
USA

508-548-8700 (voice)
508-457-2310 (FAX)
whsc_data_contact@usgs.gov
Contact_Instructions:
The metadata contact email address is a generic address in the event the person is no longer with USGS.
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/SB_data_release/DR_P9PP35F4/2017057FA_2019009FA_multispectral_imagery.faq.html>
Generated by mp version 2.9.51 on Tue Dec 27 10:11:20 2022