HR: 1340h
AN: IN43B-0332    [Abstracts]
TI: New Visualization Techniques to Analyze Ultra-High Resolution Four-dimensional Surface Deformation Imagery Collected With Ground-based Tripod LiDAR
AU: * Kreylos, O
EM: kreylos@cs.ucdavis.edu
AF: Institute for Data Analysis and Visualization (IDAV), University of California, One Shields Avenue, Davis, CA 95616 United States
AU: Bawden, G W
EM: gbawden@usgs.gov
AF: US Geological Survey, 3020 State University Drive East, Modoc Hall Suite 4004, Sacramento, CA 95819 United States
AU: Kellogg, L H
EM: kellogg@geology.ucdavis.edu
AF: Department of Geology, University of California, One Shields Avenue, Davis, CA 95616 United States
AB: We are developing a visualization application to display and interact with very large (tens of millions of points) four-dimensional point position datasets in an immersive environment such that point groups from repeated Tripod LiDAR (Light Detection And Ranging) surveys can be selected, measured, and analyzed for land surface change using 3D~interactions. Ground-based tripod or terrestrial LiDAR (T-LiDAR) can remotely collect ultra-high resolution (centimeter to subcentimeter) and accurate (± 4 mm) digital imagery of the scanned target, and at scanning rates of 2,000 (x, y, z, i) (3D~position~+ intensity) points per second over 7~million points can be collected for a given target in an hour. We developed a multiresolution point set data representation based on octrees to display large T-LiDAR point cloud datasets at the frame rates required for immersive display (between 60 Hz and 120 Hz). Data inside an observer's region of interest is shown in full detail, whereas data outside the field of view or far away from the observer is shown at reduced resolution to provide context. Using 3D input devices at the University of California Davis KeckCAVES, users can navigate large point sets, accurately select related point groups in two or more point sets by sweeping regions of space, and guide the software in deriving positional information from point groups to compute their displacements between surveys. We used this new software application in the KeckCAVES to analyze 4D T-LiDAR imagery from the June~1, 2005 Blue Bird Canyon landslide in Laguna Beach, southern California. Over 50~million (x, y, z, i) data points were collected between 10 and 21~days after the landslide to evaluate T-LiDAR as a natural hazards response tool. The visualization of the T-LiDAR scans within the immediate landslide showed minor readjustments in the weeks following the primarily landslide with no observable continued motion on the primary landslide. Recovery and demolition efforts across the landslide, such as the building of new roads and removal of unstable structures, are easily identified and assessed with the new software through the differencing of aligned imagery.
DE: 0520 Data analysis: algorithms and implementation
DE: 0530 Data presentation and visualization
DE: 1294 Instruments and techniques
DE: 1295 Integrations of techniques
DE: 1810 Debris flow and landslides
SC: Earth and Space Science Informatics [IN]
MN: Fall Meeting 2005