Lidar DSM?

[MrCarbon]

What is the workflow to create a DSM or DEM from lidar data?

With photogrammetry, you fly over an area collect images and then upload them to a website that does the processing for you and out comes a geo reference map.

Is there a similar way to create DEM/DSM with lidar?

 

[Richard R]

In a word, yes. Many programs will take lidar data (either .las or .xyz files and create DEM type (terrain elevation) maps. check out Fugro, QuickTerrain, QGIS and others. Note, true DEM where artifacts buildings and other manmade structures and trees are removed leaving 'bare earth' surfaces require quite a bit of specialized processing.

 

[alokbhargava]

Wow you guys are so professional!!!!

 

[MrCarbon]

Interesting. There are some pretty small lidar devices out there now for sUAS. It would be interesting to play with one. [emoji848]

 

[MrCarbon]

In a word, yes. Many programs will take lidar data (either .las or .xyz files and create DEM type (terrain elevation) maps. check out Fugro, QuickTerrain, QGIS and others. Note, true DEM where artifacts buildings and other manmade structures and trees are removed leaving 'bare earth' surfaces require quite a bit of specialized processing.

To create the "bare earth" model or DSM I think its called, do you need a device that is capable of doing that or that strictly part of the post processing?

 

[r62ewa]

To create the "bare earth" model or DSM I think its called, do you need a device that is capable of doing that or that strictly part of the post processing?

Photogrammetry software Pix4DMapper Pro now has the functionality to process your images, generate a DSM and also in one of their latest versions it also automatically processes the DSM and generates a DTM, "bare earth" model as you say.

You can download Pix4DMapper Pro for a free 15 day trial and have full access to all functionality so you can try generating a DTM. Of course once you become proficient with the software you can also refine and edit the DSM to receive better results but the possibility is there if you have a computer than can run the Pix4D program.

 

[Richard R]

I'll have to check them out. True bare earth where structures and trees have been removed is pretty sophisticated and computationally intensive. It's difficult enough to do working with Lidar data, trying to do it photometricaly has to be a bear! It would take some pretty ingenious filters to 'mow down' the trees and buildings.

 

[r62ewa]

Here's the link to the Pix4D DTM generation feature DTM Extraction of Pix4Dmapper - Algorithm from Recent Research