best lasground parameters for archaeological DTMs

[Martin Isenburg]

Hello,

I got word from Agata Klimczyk of Ludwig Boltzmann Institute about a study on finding the best parameters for ground-classification of airborne LiDAR for archaeology. The default settings of various softwares are rarely the best for this particular purpose because an "archaeological DTM" is not just the bare-earth terrain of a standard DTM but includes relevant man-made objects like walls, ruins, burial mounds, etc. If you use lasground of LAStools for archaeological purposes you should read up on Agata's findings:

http://lbi-archpro.org/als-filtering/lbi-project/results/lastools/

Regards,

Martin @rapidlasso

--

http://rapidlasso.com - fast tools to filter your LiDARs

[agaklim...@gmail.com]

Hello,

I would like to add few comments on our project. In the project finally we followed the standard definition of the DTM. This was due to the fact that most software packages are designed to follow it as well and keeping the walls in the models was simply not possible without segmenting the terrain... Therefore we focused on the quality of derived terrain only. I am working on another project where a new algorithm will be designed or implemented into existing one in order to be able to create the "archaeological DTMs" according to the needs. But this is still in a preliminary state.

The parameters that were chosen as the best ones for a software package were adjusted to our point cloud and I would not say that they are the best parameters for any point cloud used for archaeological purpose. The chosen parameters work well with dense point clouds (last pulse density: 8 points per m2), acquired in a leafless conditions, over an area without big man-made objects (houses etc) and adjusted for output DTM of 20cm grid size.

Our project does not give the direct answers but tries to show how to work with a software, which parameters are available and finally in guidelines we present our comments on each parameter.

The webpage is designed for ALS beginners, to support them in the first trials but the ALS experts may contribute as well by valuable comments and sharing the filtering parameters that worked well for them.

I would like to encourage you all to visit our webpage, comment on it and share the parameters with other ALS users. 

Thanks you Martin for introducing our project on your forum!

best wishes,

Agata