USGS CoastCam CACO-01 at Head of the Meadow Beach, Cape Cod National Seashore, Massachusetts (2019 to 2024): Imagery Data

Before mounting the CoastCam at the beach, the cameras (FLIR Blackfly 50S5C-C) were used to take intrinsic camera calibration images. Please refer to the CACO01_calibration_metadata record included in this data release for more information on the calibration process. The camera consists of two cameras which were installed on a bluff overlooking Head of the Meadow Beach, approximately 200 meters southeast of the parking lot, hose clamped onto a short aluminum pole. Camera one (c1) points alongshore to the north and has a 12 mm lens while camera two (c2) points offshore with an 8 mm lens (see browse graphic CACO01_CoastCam_browse.png). The cameras are connected to an Odroid-XU4 controller with a ATandT cradlepoint modem, powered by a solar charging system comprised of lithium batteries, a Renogy Voyager solar charge controller, and two Renogy 100W solar panels. Field activities related to this step include 2019-041-FA and 2019-043-FA.

The cameras were programmed in HOTM (v 3.2, https://github.com/Coastal-Imaging-Research-Network/hotm2/blob/master/hotm2.a.pdf) software to collect three-band (reg-green-blue) images every half hour and take video for 10 minutes at 2Hz. The images included in this data release were collected from December 13th, 2019 to March 22nd, 2024. Each time the camera was activated, there were five resultant image products collected: the "snapshot" ("snap") image is the first frame of the video; the time exposure ("timex") image is the average of all frames within the 10 minute video; the "variance" ("var") image shows the standard deviation of pixel intensity throughout the video; the brightest ("bright") image shows the brightest pixel values throughout the video; and the darkest ("dark") image shows the darkest pixel values throughout the video (see browse graphic CACO01_imagery_browse.png). The control computer acquires and stores the images and products produced locally and twice per hour syncs data to the AWS cloud server. The data is transmitted to the remote storage server via the cellular modem. Step was monitored and processed by E.D Marsjanik and C.R. Sherwood, date refers to the last day imagery data was collected.

All the JPEG images were renamed to ensure unique filenames and compliance with the USGS Coastal and Marine Hazard and Resources Program's (CMHRP) best practices for image naming convention. Images were renamed with the image acquisition date and Greenwich Mean Time (GMT) in computer and human readable format, the camera location, the camera number, and the image type that distinguishes among the five camera outputs. For example, image name '1614895200.Thu.Mar.04_22_00_00.GMT.2021.CACO-01.c1.snap.jpg', where 1614895200 is the 10-digit epoch time convention of the date and time, Thu is the three character day of the week, Mar is the three character month, 04 is the two digit day of the month, 22_00_00 is the GMT time in HH_MM_SS format, 2021 is the year, CACO-01 is the camera location, c1 is the camera number, and snap is the image type. This step and all following were done by J. Over.

Images were sorted into “Useable” and “Unusable” based on exposure and image subject. For example, image sets that were completely black because they were taken at night were deemed unusable. Images that were completely obscured by sand were also deemed unusable. This process was done manually and in batches by time. Images that are unusable may have been missed. This process was done by J. Over and identified ~90,000 unusable images.

The renamed useable images were geotagged and processed to add additional information required by the USGS to the exchangeable image file format (EXIF) and other imagery headers using PyExifTool Python library (https://pypi.org/project/PyExifTool/, version: 0.5.6). A list of all the useable images is provided in CACO01_ImageList.csv.
The following describes an example of the Python dictionary object with each entry in the dictionary being a tag-value pair written to each image in the data release: tags = { 'Copyright': 'Public Domain', 'CopyrightNotice': 'Public Domain - please credit U.S. Geological Survey', 'Artist': 'USGS WHCMSC', 'Make': 'FLIR', 'Model': 'Blackfly 50S5C-C', 'GPSLatitude': '42.05049347, 'GPSLongitude': '-70.07738362', 'GPSMapDatum': 'EPSG:6318 NAD83 (2011)', 'GPSAreaInformation': 'camera pole location surveyed with RTK-GNSS', 'GPSLatitudeRef': 'N', 'GPSLongitudeRef': 'W', 'Credit': 'U.S. Geological Survey', 'Contact': 'whsc_data_contact@usgs.gov', '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', 'AttributionURL': 'https://doi.org/10.5066/P95C0DGM', 'Author': 'Jin-Si R. Over, Christopher R. Sherwood, Eric D. Marsjanik, Jonathan S. Borden, Athina M.Z. Lange', 'XMP-photoshop:Credit': 'U.S. Geological Survey', 'iptcCore:CreatorWorkEmail': 'whsc_data_contact@usgs.gov','Rights': 'Public Domain', 'ExternalMetadataLink': 'https://www1.usgs.gov/pir/api/identifiers/USGS:60d6125bd34e9603936761eb'}.
The camera pole location was surveyed with RTK gear, which gives us the UTM and Lat/Long simultaneously in the file we download off of the device. The EXIF GPS Latitude/Longitude/Position tags are in NAD83(2011).
Additionally, tags were added to the Python dictionary object that have different values for each image depending the filename and/or date when the image was captured. These tags are included as follows:
'Caption-Abstract': 'The [IMAGE PRODUCT] image represents [X]. This image was captured from a stationary camera (CACO-01 [c#]) at Cape Cod National Seashore, Massachusetts, Field Activity Number: [INSERT FA] on [INSERT CREATION DATETIME].
'Caption': 'The [IMAGE PRODUCT] image taken at CACO-01 [c#] at Cape Cod National Seashore, Massachusetts, USA on [INSERT CREATION DATETIME].'
'Comment': '[IMAGE PRODUCT] image for [INSERT CREATION DATETIME]; This image was captured from a stationary camera (CACO-01 [c#]) at Cape Cod National Seashore, Massachusetts. Field Activity Number: [INSERT FA]'
'Description':'https://cmgds.marine.usgs.gov/services/activity.php?fan=[INSERT FA]; This image was captured from a stationary camera (CACO-01 [c#]) at Cape Cod National Seashore, Massachusetts.'
'Keywords': "Head of the Meadow Beach, Cape Cod National Seashore, Massachusetts, CoastCam, USGS, [IMAGE PRODUCT], remote sensing", dependent on the image product type.
Where [IMAGE PRODUCT] is the type of image product (snap, timex, var, bright, dark) and [X] is the product description, [c#] refers to either camera 1 or 2, [INSERT FA] refers to the relevant field activity for the image, and [INSERT CREATION DATETIME] refers to the original date and time of the image in YYYY:MM:DD HH:MM:SS GMT.
The UserComment EXIF metadata field was used to store the camera intrinsics and extrinsics in the image metadata. The The UserComment has a nested dictionary structure. The highest-level dictionary contains two nested dictionaries as well as a note explaining the structure of the UserComment field. One nested dictionary contains the relevant intrinsic (NU, NV, coU, coV, fx, fy, d1, d2, d3, t1, t2) and extrinsic (x, y, z, azimuth, tilt, roll) data variables. See CACO02_calibration_metadata for descriptions of variables. The extrinsic variables include both horizontal and vertical location of the camera in NAD83(2011)/UTM 19N + NAVD88 (GEOID 18). We recommend to the user to calculate their own EO data based on the dates of the imagery used. The other nested dictionary contains text descriptions for each of the variables in the dictionary of data variables. The calibration date and GPS DateStamp field indicates the date of the EO.
The GPSDateStamp field indicates the date of the extrinsic calibration. The GPSTimeStamp relates to the time of the extrinsic calibration and is 00:00:00 because that info is irrelevant, use the image name, comment tag, or the DateTimeOriginal Exif tag for the actual image information.
To read out the imagery header information to a CSV file the command is: 'exiftool -csv *.jpg > .\ allheaders.csv'. Specific tags may be specified with this command, if preferred. Or use the online tool https://exif.tools/ (accessed May 9, 2025)

Images in this release uploaded into the USGS Imagery Data System: https://cmgds.marine.usgs.gov/idsviewer/data_release/10.5066- P95C0DGM. Step processed by J.R. Over.