Data Research

Data research activities focus on the evaluation of new UAS compatible sensors and development of data processing techniques to take advantage of increased resolutions and accuracy to generate better traditional and new data products to help answer scientific and natural resource questions.

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An orthophoto is an undistorted aerial photograph with a completely uniform scale that allows it to function as a map. A significant amount of geometric correction, known as orthorectification, is required to bring about this high level of uniformity. High resolution imagery with ground sample distances of less than six inches can be derived from low-altitude UAS flights using commercial off-the-shelf cameras and computer vision (structure from motion) software.

An enlarged area of an orthophoto base map created from a mosaic of 160 images taken from approximately 400 feet AGL over the Sycan River in the Klamath Basin.
An enlarged area of an orthophoto base map created from a mosaic of 160 images taken from approximately 400 feet AGL over the Sycan River in the Klamath Basin.
An enlarged area of an orthophoto base map created for conducting waterfowl (pelican) census counts on the Chase Lake National Wildlife Refuge in North Dakota.
An enlarged area of an orthophoto base map created for conducting waterfowl (pelican) census counts on the Chase Lake National Wildlife Refuge in North Dakota.
Natural color imagery acquired with the Ricoh GR camera mosaicked to create a orthophoto base map to support individual tree identification in Northeast Indiana.
Natural color imagery acquired with the Ricoh GR camera mosaicked to create a orthophoto base map to support individual tree identification in Northeast Indiana.

A unique capability for a camera conversion allows a low-cost method of capturing near-infrared imagery useful for vegetation analysis on low-altitude UAS aerial flights. The camera conversion involves utilizing a notch filter that blocks the low to mid red light range. The result is a camera sensor that detects the red (near infrared edge of the electromagnetic spectrum) centered around 690-720 nm near infrared, green, and blue.

Color infrared orthophoto of Sycan River
A color infrared orthophoto base map created from a mosaic of 160 images taken with the Canon s100 color infrared converted camera from approximately 400 feet AGL over the Sycan River in the Klamath Basin in Oregon.
Color infrared orthophoto of Ruby Lake
A color infrared orthophoto base map image taken with the Canon SX 230HS camera from approximately 200 feet AGL over the Ruby Lake National Wildlife Refuge in Nevada.

Geographic point clouds are a set of data points in a three-dimensional coordinate system and typically represented as X, Y and Z. Point clouds, which can vary from sparse to dense, can be collected by Light Detection And Ranging (LiDAR) scanners or derived by using photogrammetric (structure from motion) techniques on aerial imagery. Point cloud data is an invaluable resource for a variety of geographic applications that evaluate and monitor landscape change.

Point cloud data overlaid on mosaicked aerial imagery generates realistic natural color 3D models for use in computer simulations, display as a two-dimensional image via 3D rendering, or printing from a 3D printer.

Dense Point Cloud generated in PhotoScan with one level of classification of the Carrizo Plain area.
Dense Point Cloud generated in PhotoScan with one level of classification of the Carrizo Plain area.
3D model of Carrizo Plain
3D model of the Carrizo Plains area of California.Final Orthophoto mosaic draped over the elevation model in PhotoScan of the Carrizo Plain area
Rendering of the Devils Tower 3D model
Rendering of the Devils Tower 3D model
Close up of the model showing detailed rock surface
Close up of the model showing detailed rock surface

Feature extraction is a method of automating the process of recognizing spectral patterns within an image and outlining or classifying those features into a newly defined dataset. UAS low-altitude flights allow for this to be accomplished on a very large scale with the high resolution images enabling very accurate identification of features.

Feature extraction of Joshua Trees
Yellow dots indicate the location of Joshua Trees in the Mojave Desert based on feature extraction techniques that utilized the tree's unique spectral signature.
Feature extration of American White Pelicans
Extracted locations for pelican nests (red), cormorant nests (blue), and gull and snowy egret non-nesting (black), at the Chase Lake National Wildlife Refuge.
Feature extration of shoreline
Polygonal samples of various water reflectivity were used to extract the stream bank of the Sycan River (blue lines).

A unique capability for a camera conversion allows a low-cost method of capturing near-infrared imagery useful for vegetation analysis on low-altitude UAS aerial flights. The conversion involves utilizing a notch filter that blocks the low to mid red light range. The result is a sensor that detects the red (near infrared edge of the electromagnetic spectrum) centered around 710-740 nm, green, and blue. NDVI calculations that create a standardized index utilizing the amount of infrared light that is reflected from a plant and has a strong correlation to the health of the plants imaged. Traditionally the bright red display of the color ramp indicates healthy or highly reflective plants and the blue color indicating the lower reflectivity and possibly less healthy vegetation.

NDVI of Sycan River
NDVI derived from a mosaic of near infrared imagery taken from approximately 400 feet AGL over the Sycan River in the Klamath Basin in Oregon.
NIR NDVI in West Virginia Black and White NDVI in West Virginia Color NDVI in West Virginia
Images from a Canon SX260 taken at 400 AGL of a West Virginia mining impoundment (top- color IR mosaic, middle- black & white mosaic, bottom- derived NDVI).
NIR NDVI in Aurora Colorado NDVI in Aurora Colorado
Color infrared image taken by a Canon SX230 camera (top) and derived NDVI product (bottom) of the Ruby Lake National Wildlife Refuge.

A contour line (or "contour") joins points of equal elevation (height) above a given level, such as mean sea level. A contour map is a map illustrated with contour lines, for example a topographic map, which shows valleys and hills, and the steepness of slopes. The contour interval of a contour map is the difference in elevation between successive contour lines.

Contours of Kentucky coalmine
A derived 3-foot contour shaded elevation map over mining stockpiles in an Eastern Kentucky coal mining area.
Contours of the Piute Valley
Contours, derived based on a GSD of 1.4 inch, overlaid on an orthophoto mosaic of the Piute Valley in the Mojave Desert.
Contours of Devils Tower
Derived 1-foot contour intervals overlaid on an orthophoto mosaic of the Devils Tower National Monument in Wyoming.

A Digital Surface Model (DSM) is a digital cartographic/geographic dataset of reflective surface elevations of horizontal and vertical (xyz) coordinates. The surface elevations for ground positions are sampled at regularly spaced horizontal intervals and can be derived at very high ground resolution when using a low-altitude UAS with standard commercial off-the-shelf cameras. DSM's contain elevations of natural terrain features in addition to vegetation and cultural features such as buildings and roads.

DSM of Sycan River
DSM created from a mosaic of 160 images taken from approximately 400 feet AGL over the Sycan River in the Klamath Basin in Oregon.
DSM of Platte River
DSM created from a mosaic of 900 images taken from approximately 200-400 feet AGL over the Platte River near Kearney, Nebraska.
DEM from high-resolution color imagery (5-10 cm pixel size) and elevation data (6-10 cm vertical and 2-4 cm horizontal resolution range) of the West Fork Mine in Missouri.

Volumetric calculations begin with the generation of accurate elevation models, traditionally based on data derived from manual on-site measurements, surveying techniques, and photogrammetric methods. Now the introduction of UAS based collection of very high-resolution aerial imagery offers a low-cost option for generating the elevation models needed to support the creation of accurate volumetric measurements.

Elevation model of Kentucky coalmine
An elevation model derived using the Agisoft PhotoScan software with 350 images collected at 200-300 feet AGL over mining stockpiles in an eastern Kentucky coal mining area.
Volumetric measurements of Kentucky coalmine
Volumetric calculations for the eastern Kentucky coal mining area that derived from the elevation model and then graphically displayed using the Global Mapping software.

Keyhole Markup Language (KML) is an XML notation for expressing geographic annotation and visualization within internet-based, two-dimensional maps and three-dimensional Earth browsers. The KML file specifies a set of features (place marks, images, polygons, 3D models, textual descriptions, etc.) for display in Google Earth or any other geospatial software that supports KML encoding.

KML of Sycan River
A color infrared orthophoto base map of the Sycan River in the Klamath Basin in Oregon in KML.
KML of Mill Lake
A derived natural color orthophoto image mosaic of Mill Lake converted into KML.
KML of Kentucky coalmine
A digital elevation model over a coal mining area of eastern Kentucky converted into KML.
AgiSoft PhotoScan Professional Edition - Generate high resolution georeferenced orthophotos (up to 5 cm accuracy with GCP) and exceptionally detailed DEMs / textured polygonal models. The fully automated workflow enables a non-specialist to process thousands of aerial images on a desktop computer to produce professional class photogrammetric data.

GOM Media Player Uses a Burst Capture Routine to automatically capture still frame images at set intervals.

Blue Marble Geographics Global Mapper - Viewer/editor capable of displaying the most popular raster, elevation and vector datasets.

ENVI - ENVI uses proven scientific methods and automated processes to help easily extract information from geospatial imagery.

ImageJ - ImageJ is a public domain Java image processing program inspired by NIH Image for the Macintosh. It runs, either as an online applet or as a downloadable application, on any computer with a Java 1.4 or later virtual machine. Downloadable distributions are available for Windows, Mac OS, Mac OS X and Linux.

Exiv2 - Exiv2 is a C++ library and a command line utility to manage image metadata. It provides fast and easy read and write access to the Exif, IPTC and XMP metadata of images in various formats. Exiv2 is available as free software and with a commercial license, and is used in many projects.