Abstract:

This dataset contains aerial drone imagery and image reference data (latitude, longitude, altitude, pitch, roll, and heading). The images were acquired by a professional drone that was equipped with a Sony A6000 mirrorless camera and a RTK GPS. Image positions were recorded using a time synchronization cable that was connected to the camera's hot shoe and the RTK GPS. These images and their associate reference data were used to create orthomosaics using Agisoft PhotoScan Professional v1.4.4 (hereafter referred to as 'PhotoScan'). PhotoScan also computes the lens distortion and the errors in each of the position and orientation variables. This dataset includes drone imagery (in TIFF format) and the reference data for each image for two areas in Grand Isle, Louisiana. The first set of imagery was collected 2017-04-18 over a dock on the north side of the island, and these images were processed in PhotoScan to estimate the position and orientation errors of the sensors on the drone. Therefore, the dataset on 2017-04-18 includes a digital elevation model and an orthomosaic (both in geotiff format), as well as the processing report (in pdf format). The second set of imagery was collected 2017-04-22 over a beach on the south side of the island. These images include waves and other moving ocean features and were not processed in PhotoScan, which assumes a stationary subject in all images.

Suggested Citation:

Carlson, Daniel F., Henry Chang, Cameron Hunt, Karina Khazmutdinova, Coby Leuschke, John Lodise, and Urs Treier. 2023. Aerial drone imagery of coastal areas of Grand Isle, Louisiana, 2017-04-18 and 2017-04-22. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/PZVMP340

Purpose:

The images collected on 2017-04-18 were used to assess the direct georectification potential of low-altitude drone imagery with low-quality inertial motion unit (IMU) data. The images collected on 2017-04-22 can be used to identify waves and, using feature tracking, the wave speed, which can then be used to estimate near-shore bathymetry.

Data Parameters and Units:

Latitude (WGS84, decimal degrees]), longitude (WGS84, [decimal degrees]), height/altitude [meters above sea level]; longitude, latitude, and height/altitude accuracies [meters]; yaw/heading, pitch, and roll [degrees]; yaw/heading, pitch, and roll accuracies [degrees].

Methods:

The Sony A6000 was equipped with a 17 mm lens, and images were acquired at 1 second intervals and were stored in Sony's raw format (.ARW). The raw images were converted to 16-bit TIFFs using Sony's free Imaging Edge software. The drone was equipped with an Emlid Reach RTK GPS, and a synchronization cable between the camera's hot shoe and the Reach module ensured accurate timing of each image. The Emlid Reach GPS data were processed using the open source RTKLIB software following Emlid's guidelines, and the NOAA Continuously Operating Reference Station (CORS) in Grand Isle was used as a fixed base station.

Instruments:

Sony A6000 digital camera, Emlid Reach RTK GPS

Individual Files: