[GRASS-user] "raised field" objects : how to extract and export ?

[Moritz Lennert]

On 21/03/17 23:45, dandrigo wrote:
> Dear all,
>
> I m working on windows 10.
> In input, i have a .LAS "GROUND_only" lidar point cloud (4 millions points).
> We 're interested in geomorphological microstructures called raised field
> (ground elevation due to cultivated areas ).
> I attach a SS representing this cloud file.
>
> <http://osgeo-org.1560.x6.nabble.com/file/n5313524/ss_cloud_lidar_GROUND_only.jpg>
>
>
> 1/ We would like to classify our input ground point cloud in order to
> separate the points constuing those "raised field"  and other ground points
> "NON ground raised field" points.
> 2/ Once the classification will done, we would like to be able to export the
> result toward an new .las or shp (ideally with usefull attribute information
> like class_id, z value, etc.).
> We would like generate a Multipoint layer only for those "raised field
> objects". All the points constituing an object "raised field" must be strore
> into the same row( entity).
>
> Could you tell me how to that?

I think you will have to first clearly define your criteria for 
classifying the points as "raised fields" or "normal" ground. Then we 
might be able to point you to the relevant tools in GRASS.

Moritz