Set LAS Class Codes Using Raster (3D Analyst)

Summary

Classifies LAS points using cell values from a raster dataset.

Usage

• This tool requires an integer raster. The cell values of the raster will define the class code of the LAS points within the cell's extent. Any cell value that is beyond the range supported by the LAS format will be ignored. Cells with No Data values result in no change to the LAS points. Use the Reclassify tool if the raster's cell values need to be changed to have the necessary class code values supported by the input LAS files.

• Unlike other classification tools which only operate on certain class codes, this tool can modify all LAS points that are contained in a given cell. A LAS dataset layer can be used to limit the points being processed by filtering them using classification codes, return values, and classification flags. The LAS dataset's point filters can be defined in the Layer Properties dialog box or through the Make LAS Dataset Layer tool.

• For best results, use a raster dataset that is in the same projection as the LAS dataset. A raster with a coordinate system other than that of the LAS dataset will be reprojected on the fly, which can introduce alignment discrepancies that may yield unexpected results. If the raster has a different coordinate system, consider using the Project Raster tool to reproject it into the spatial reference of the LAS dataset.

• This tool provides a way of leveraging the results obtained from image classification to classify a LAS dataset point cloud. For example, the Classify LAS Ground tool may identify LAS points capturing roads, bodies of water, and other low objects which could be easily discerned from imagery. If the image accurately captures the object at a resolution suitable for classifying the point cloud, the image classification result can be used with the ground filtered LAS points to provide better LAS classification.

Parameters

Dialog

Label	Explanation	Data Type
Input LAS Dataset	The LAS dataset that will be processed.	LAS Dataset Layer
Input Raster	The integer raster with cell values that will be used to assign classification codes for LAS points. The cell values must not exceed the class codes that are supported by the input LAS files.	Raster Layer; Mosaic Layer
Compute statistics (Optional)	Specifies whether statistics will be computed for the .las files referenced by the LAS dataset. Computing statistics provides a spatial index for each .las file, which improves analysis and display performance. Statistics also enhance the filtering and symbology experience by limiting the display of LAS attributes, such as classification codes and return information, to values that are present in the .las file. Checked—Statistics will be computed. This is the default. Unchecked—Statistics will not be computed.	Boolean
Processing Extent (Optional)	The extent of the data that will be evaluated. Current Display Extent —The extent will be based on the active map or scene. This option is only available when there is an active map. Draw Extent —The extent will be based on a rectangle drawn on the map or scene. This option will create a feature class in the project geodatabase and add a layer to the map. The feature class will have the same coordinate system as the map. Note: This option is not available in the Environments dialog box. It is only available from a tool parameter with an extent data type or from the Environments tab on a tool dialog box. Note: When the Enable and disable editing from the Edit tab editing option is checked, you must enable editing on the Edit ribbon tab to draw the extent. Extent of a Layer —The extent will be based on an active map layer. Use the drop-down list to choose an available layer or use the Extent of data in all layers option to get the combined extent of all active map layers, excluding the basemap. This option is only available when there is an active map with layers. Each map layer has the following options: All Features —The extent of all features in the layer. Selected Features —The extent of the selected features in the layer. Visible Features —The extent of visible features in the layer. Note: The extents from the Selected Features and Visible Features options are only available for feature layers. Browse —The extent will be based on an existing dataset. Intersection of Inputs —The extent will be based on the minimum or intersecting extent of all inputs. If no inputs overlap, a null extent with all zeros will result. Union of Inputs —The extent will be based on the maximum or combined extent of all inputs. Clipboard —The extent can be copied to and from the clipboard. Copy Extent —Copies the extent coordinates and coordinate system to the clipboard. Paste Extent —Pastes the extent coordinates and, optionally, the coordinate system from the clipboard. If the clipboard values do not include a coordinate system, the extent will use the map’s coordinate system. Note: The extent coordinates are copied to and pasted from the clipboard using the same formatting and order as the ArcPy Extent object: x-min, y-min, x-max, y-max, and the spatial reference. Reset Extent —The extent will be reset to the default value. Manually entered coordinates—The coordinates must be numeric values and in the active map's coordinate system. Caution: The map may use different display units than the entered coordinates. The use of a cardinal direction (N, S, E, W) is not supported. Use a negative value sign for south and west coordinates.	Extent
Processing Boundary	A polygon feature that will define the area of interest to be processed.	Feature Layer
Process entire LAS files that intersect extent (Optional)	Specifies how the area of interest will be used in determining how .las files will be processed. The area of interest is defined by the Processing Extent parameter value, the Processing Boundary parameter value, or a combination of both. Unchecked—Only LAS points that intersect the area of interest will be processed. This is the default. Checked—If any portion of a .las file intersects the area of interest, all the points in that file, including those outside the area of interest, will be processed.	Boolean
Update pyramid (Optional)	Specifies whether the LAS dataset pyramid will be updated after the class codes are modified. Checked—The LAS dataset pyramid will be updated. This is the default. Unchecked—The LAS dataset pyramid will not be updated.	Boolean

Derived Output

Label	Explanation	Data Type
Output LAS Dataset	The reclassified LAS dataset.	LAS Dataset Layer

Python

arcpy.ddd.SetLasClassCodesUsingRaster(in_las_dataset, in_raster, {compute_stats}, {extent}, boundary, {process_entire_files}, {update_pyramid})

Name	Explanation	Data Type
in_las_dataset	The LAS dataset that will be processed.	LAS Dataset Layer
in_raster	The integer raster with cell values that will be used to assign classification codes for LAS points. The cell values must not exceed the class codes that are supported by the input LAS files.	Raster Layer; Mosaic Layer
compute_stats (Optional)	Specifies whether statistics will be computed for the .las files referenced by the LAS dataset. Computing statistics provides a spatial index for each .las file, which improves analysis and display performance. Statistics also enhance the filtering and symbology experience by limiting the display of LAS attributes, such as classification codes and return information, to values that are present in the .las file. COMPUTE_STATS—Statistics will be computed. This is the default. NO_COMPUTE_STATS—Statistics will not be computed.	Boolean
extent (Optional)	The extent of the data that will be evaluated. MAXOF—The maximum extent of all inputs will be used. MINOF—The minimum area common to all inputs will be used. DISPLAY—The extent is equal to the visible display. Layer name—The extent of the specified layer will be used. Extent object—The extent of the specified object will be used. Space delimited string of coordinates—The extent of the specified string will be used. Coordinates are expressed in the order of x-min, y-min, x-max, y-max.	Extent
boundary	A polygon feature that will define the area of interest to be processed.	Feature Layer
process_entire_files (Optional)	Specifies how the processing extent will be applied. PROCESS_EXTENT—Only LAS points that intersect the area of interest will be processed. This is the default. PROCESS_ENTIRE_FILES—If any portion of a .las file intersects the area of interest, all the points in that file, including those outside the area of interest, will be processed.	Boolean
update_pyramid (Optional)	Specifies whether the LAS dataset pyramid will be updated after the class codes are modified. UPDATE_PYRAMID—The LAS dataset pyramid will be updated. This is the default. NO_UPDATE_PYRAMID—The LAS dataset pyramid will not be updated.	Boolean

Derived Output

Name	Explanation	Data Type
derived_las_dataset	The reclassified LAS dataset.	LAS Dataset Layer

Code sample

SetLASClassCodesUsingRaster (Python window)

The following sample demonstrates the use of this tool in the Python window.

import arcpy
arcpy.ddd.SetLasClassCodesUsingRaster("Jacmel.las", "reclass.tif", "COMPUTE_STATS")

Environments

Extent, Current Workspace, Geographic Transformations