How to extract building footprints using nDSM? The nDSM was created from a point cloud (not LIDAR data).

NikosTziokas

I have created a nDSM (DSM-DEM). I have place the threshold value to 2m (in this way I have eliminated objects such as shrubs).

My problem is how to differentiate the buildings from the other objects (for example trees). 

I am using ArcMap 10.4.

Thank you in advance.

ArthurCrawford01

Hello Nikos,

There are several ways you can try to do this:

1. Use imagery that has been classified as a mask for the trees to remove them.

2. Then convert the raster to polygons.

3. Use Regularize Building Footprints tool to clean up the buildings (straight edges).

If you look on my blog, you will see more detail on the Regularize Building Footprint Tool under 

Regularize Building Footprint Tool - Clean up raw extracted features extracted from lidar or imagery.

A tool set has been developed for ArcGIS Pro to extract buildings from lidar point clouds. You can find it in the ArcGIS Imagery Workflows on ArcGIS Online under 3D Mapping with Lidar Point Clouds.

3D Mapping with Lidar Point Clouds

http://www.arcgis.com/home/item.html?id=06dfb37ca4b94e05bd3507cc4424804f

This process uses raster functions to remove trees fairly well with texture analysis.

I heavily suggest using ArcGIS Pro to do this.

Thanks,

Arthur Crawford - Esri