Available with 3D Analyst license.
A LAS dataset stores reference to one or more LAS files on disk, as well as to additional surface features. A LAS file is an industry-standard binary format for storing airborne lidar data. Optimized LAS (.ZLAS) files are also supported with the LAS dataset. The LAS dataset allows you to examine LAS files, in their native format, quickly and easily, providing detailed statistics and area coverage of the lidar data contained in the LAS files.
A LAS dataset can also store reference to feature classes containing surface constraints. Surface constraints are breaklines, water polygons, area boundaries, or any other type of surface feature enforced in the LAS dataset. Surface constraints are stored in geodatabase feature classes or shapefiles, which are usually derived from some sort of remote sensing technique like photogrammetry.
The list below includes common examples of how to benefit from using LAS datasets to incorporate lidar data in ArcGIS Pro. With LAS datasets, you can do the following:
- Store references to many LAS files and surface data at once for a specific project.
- Quickly display lidar data as point clouds or a triangulated surface in 2D or 3D.
- Visually compare the lidar points against existing GIS data for data validation, such as building data.
- Quickly conduct a statistical analysis on LAS files and lidar points.
- Conduct initial quality assurance and quality control, such as assessing data coverage and point sample density, for newly acquired lidar data.
- Incorporate additional breaklines or surface features with lidar.
- Create additional surfaces such as DEMs and DSMs (LAS Dataset To Raster geoprocessing tool) or TINs (LAS Dataset To TIN geoprocessing tool).
- Create intensity images using the LAS Dataset To Raster geoprocessing tool.
- Interactively digitize new features using the LAS dataset as points and ArcGIS editing tools.
- Update with newly acquired LAS or surface data.
- Share your LAS dataset data using the mosaic dataset.
- Examine spatial distribution of various lidar point metrics using the LAS Point Statistics As Raster geoprocessing tool.
- Manually fix errors in class codes using interactive editing techniques available with classification editing and profile viewing.
You can quickly change the view of the LAS dataset into a TIN-based surface, similar to the TIN or terrain dataset display. The LAS dataset allows you to work with points classified into different feature types. There are several point and surface symbology renderers available for LAS datasets. The most common symbology for LAS datasets can be accessed quickly from the Symbology pane.
The LAS dataset default display in ArcGIS Pro is as a point cloud with no filter applied. That means that all the lidar points display initially if zoomed to an extent, where thinned points display. Also, ArcGIS Pro allows single LAS and ZLAS files to be displayed and used with all the same functionality as a LAS dataset.
When a LAS dataset, or LAS or ZLAS file is added to a 3D scene in ArcGIS Pro, the points are symbolized with an elevation renderer and eye-dome lighting applied by default. Eye-dome lighting is a shading technique that improves the perception of depth and contour when viewing LAS datasets.
When a LAS dataset, or LAS or ZLAS file is added to a 2D map in ArcGIS Pro, the points are drawn with an elevation renderer only.
The LAS dataset does not import point data contained in the LAS files. It stores a reference to these LAS files and surface constraints. They are constructed very quickly, as only the header information for each LAS file needs to be accessed. Consider using the terrain dataset to work with lidar data in the geodatabase in ArcMap.
The LAS dataset is a great complement to terrain dataset and mosaic dataset-based workflows. For example, it is common to add newly acquired lidar data to a terrain dataset. The LAS dataset could be quickly generated first to conduct an initial quality assurance and quality control check on the lidar data. This LAS dataset provides all of the necessary information to know that the lidar data meets the desired quality standards before importing into the terrain dataset.
Set the projection for LAS data
To project LAS, use the Extract LAS geoprocessing tool. You can set a filter on the input LAS dataset layer to project only certain points. On the Extract LAS geoprocessing tool dialog box, go to the Environments tab and specify the output coordinate system information. Each input LAS file, not just the referenced LAS dataset, needs a proper spatial reference upon input to the tool. If input LAS files are missing a spatial reference, but the spatial reference is known, use the Create LAS Dataset tool first and select the option to create .PRJ files to get that spatial information defined. Using Extract LAS to project the LAS files creates new LAS files with the new projection.