2015 NC GIS Conference

3D Data and WebGL for Large Data Sets in Your Browser. Technology is constantly moving forward in collecting, manipulating, and visualizing large 3D data sets. In these sessions new methods of collecting and manipulating point cloud data will be demonstrated, along with new methods of displaying large 3D point and surface sets in web browsers using WebGL technologies. 

• Single Photon Lidar
           Dr. J. Marcos Sirota
  Single Photon Lidar (SPL) is now a mature operational technology, which has been developed over the last several years by Sigma Space. Multiple systems operating from 3 to 30 kft, capable of topographic and bathymetric applications have been deployed. The systems use 100-beam arrays rapidly scanned over the terrain, producing up to 3.2 million multi-stop pixels per second. Multiple returns per pixel per laser fire are recorded due to the fast recovery of the receiver, a stark contrast to typical “Geiger-mode” systems. With a receiver deadtime of only 1.6 nsec (~20 cm), obscurant multi-layer measurements are readily obtained for foliage, water or any diffuse targets with single laser firings. Swaths of 2.4 km, flying at 200 knots and with minimum point densities of 8 points/sq meter are standard for the high altitude units. Medium altitude (7,500 ft) systems produce 1.6 km swaths, for an aereal coverage of about 600 km2/ hr. Additional technical specifications, data samples, and data quality analysis will be presented.

• Commercial Geiger Mode LiDAR the Next Paradigm
           Mark Romano
  Originally developed for US military applications Harris has developed the first commercially available LiDAR system built with Geiger Mode Avalanche Photodiode (GmAPD) technology. This new technology provides significant efficiency gains for airborne LiDAR mapping when compared with currently available linear mode sensors. This system can collect very high density data (over 20 PPM) at instantaneous area of coverage rates greater than 1000 sq. km per hour providing lower cost with higher data quality.
  
  This presentation will describe the processes and technologies Harris has developed over the past 15 years for efficiently producing high density point clouds from GmAPD lidar data, and discuss how these capabilities support non-military applications. Topics to be covered include: 1) GmAPD sensing fundamentals, 2) collection strategies for GmAPD collection, and 3) automated, large volume data production systems. 4) comparisons of existing vs new technologhy project solutions. Examples of high density GmAPD products will also be shown.

• plas.io and Greyhound: Point Clouds in Your Browser
           Howard Butler
  Point cloud data have a deserved reputation for being unwieldy, noisy, redundant, unstructured, and huge. Despite this, the pace at which these data are available continues to accelerate. LiDAR, in the form of laser scans captured from aircraft, vehicles, and stationary sensors, has gone from a finicky technical oddity to a nearly everyday arrow in the quiver of a GIS practitioner looking for elevation data. Sonar captures are transforming from simple interpolated surfaces of sounding depths to detailed characterizations of the the underwater environment. Finally, Structure from Motion (SfM) technologies are enabling UAV-captured point clouds to be available to the everywoman for unprecedented cost in unprecedented volume. plas.io is standard HTML5 software that allows developers to create richly customized applications for interacting with point cloud data in your browser, and Greyhound is the open source server component that feeds those clients. Both technologies build on the PDAL and LASzip open source softwares to enable point cloud data processing and compression. All of these softwares are powered by a community of developers who use them to solve many tasks, and I will show you how you can leverage them to innovatively deliver point cloud data to your clients.