Data Access via OpenTopography
- Accessing USGS 3DEP data on OpenTopography: Access the USGS 3DEP dataset on OpenTopography. Currently, this service is limited to US academics and OT+ subscribers.
- Accessing global topography data: Access global and regional topographic data, including SRTM and ALOS, and download DEMs and visualizations.
- Using API Keys to Access OpenTopography’s Global Datasets API: Request and use an API Key for OpenTopography's global datasets API.
- Extract and Download Ground Classified Points on OpenTopography: Use the OpenTopography interface to extract and download ground classified points from a point cloud.
Dataset Preparation
- Raster resolution: Set the raster resolution from Point Cloud Density
- Extract and Download Ground Classified Points on OpenTopography: Use the OpenTopography interface to extract and download ground classified points from a point cloud.
Visualize Raster Datasets (e.g., topographic hillshades)
- Topographic Hillshades Visualization & Download on OpenTopography: What is a topographic hillshade? Why are different light azimuths and altitudes important? How to make them on OT?
- Create Topographic Hillshades in QGIS: This video tutorial covers three different methods for how to create topographic hillshade visualizations in QGIS.
- Generate Hillshades from Global Topographic Data: When making hillshades from global topographic data, it is necessary to choose the correct settings to create a proper visualization. This video tutorial covers how to set the Z-factor when generating hillshades from global topography data in QGIS.
- Visualize DEMs and Raster Topography in Matlab: Load and visualize raster datasets such as digital elevation models. The Matlab script is available from OpenTopography’s GitHub page.
Visualize Point Cloud Datasets
- Potree point cloud viewer: Use the Potree point cloud viewer as part of our treasure hunt activity. Visualize datasets by attribute such as classification, intensity or color, and make measurements
- Lastools and Lasview: Download, install, and use Lastools (specifically Lasview) to visualize point cloud data sets along with their attributes
- Visualize Point Cloud Topography in Matlab: Learn how to load and visualize lidar point cloud topography using Matlab’s lasdata function. The Matlab script is available from OpenTopography’s GitHub page.
- Visualize Point Cloud Topography with Matlab’s Lidar Toolbox: Load and visualize lidar point cloud topography using Matlab’s Lidar Toolbox with this script from OpenTopography’s GitHub .
Topographic Differencing
- Vertical Differencing on OpenTopography: Perform vertical change detection on OpenTopography, as enabled on over 20% of the mainland US and many international datasets. This shows processes including urban growth, vegetation change, river processes, earthquakes and landslides.
- 3D Differencing on OpenTopography: Perform 3D differencing on OpenTopography's web interface. This tool uses the Iterative Closest Point algorithm and measures lateral landscape shifts from earthquakes, creeping landslides, and sand dune migration.
- 3D Topographic Differencing on Matlab: Perform 3D differencing in Matlab. The Matlab script is available from GitHub.
- 3D Differencing on CloudCompare: Perform 3D differencing using CloudCompare, demonstrated on datasets that represent a make-believe but realistic earthquake along the Wasatch fault in Salt Lake City available here on OpenTopography and from NAGT/SERC .
Hydrology Tools
- TauDEM Hydrology Tools: Use TauDEM (Terrain Analysis Using Digital Elevation Models) to calculate flow direction and area contributing within hydrologic networks and visualize in QGIS.
Canopy Height Models and Ground Point Extraction
- Make a Canopy Height Model on OpenTopography: Produce a canopy height model (CHM), also known as a normalized digital surface model, on OpenTopography
- Use Lastools to Extract Ground Classified Points Use Lastools to extract and view ground classified points from a point cloud.
Geologic Mapping with Lidar Topography in ArcGIS Pro
- Playlist: Geologic mapping with lidar topography in ArcGIS Pro: This suite of 24 tutorial videos demonstrates how to use ArcGIS Pro software to construct geologic maps with step-by-step instructions using lidar data here.
3D Printing
- 3D Printing: Make 3D print file (STL) from topography data using free and open source software including the DEMto3D plugin in QGIS and 3D Builder. See how to select the size and resolution of the 3D print, how to apply a vertical exaggeration, and add a base to the 3D model.
CloudCompare Tutorials
- Measuring Fault Plane Strike and Dip: Measure geologic fault orientation from a point cloud using the Compass tool. This video was developed for this structural geology exercise focused on a virtual structural analysis of a point cloud dataset near the Southern San Andreas Fault.