Spatially Thin Lidar Layers

The spatial thinning tool reduces the density of the point cloud based on a specified threshold spacing. This tool creates a new thinned layer, and the original layer can be unloaded if desired. This tool acts on the entire point cloud layer, and does not pay attention to visual Lidar Filtering.

Select this button from the Lidar Toolbar, or by right clicking on a point cloud layer in the Control Center and going to Layer > THIN - Spatially Thin Lidar Layers.

Output Resolution

Specify the spacing that the data is thinned. This can be a multiple of the native point spacing of the point cloud(s), or a linear unit. For example, a point spacing of 4 would create a new point cloud at 1/4th of the native point spacing.

Thin Method

Minimum Elevation — the Lidar point of minimum height is kept from each 2D cell

Maximum Elevation — the Lidar point of maximum height is kept from each 2D cell

Median Elevation — the Lidar point falling in the specified percentile is kept from each 2D cell. Use a percentile value of 50 to keep the median elevation.

3D Thin (default)— the Lidar point of median height is kept from each 3D cell. This method uses a voxel grid, or 3D gridding to determine what points to keep. This method is recommended because it maintains the point spacing in 3-dimensions. The vertical Elevation Resolution can be set independently. This can be set to keep more points in steep areas, such as cliffs and sides of buildings.


This point cloud cross section has been thinned with each method.