Hi,

yes that is possible to automate this process. The main idea is to use an blur-filter on your DSM - a normalized 2D gauss kernel array for convolutions - where the size of the kernel determines the wide of the features that will be extracted. The second step is to build the difference between DSM and DSM_blured. So the small features will remain. for more theory see: https://www.isprs.org/proceedings/xxxvi/8-w2/SITTLER.pdf

Some years ago - in my former ArcGIS job - I've wrote a small python routine for ArcGis using numpy to do the job. The ArcGis script could be found here: https://files.wheregroup.com/s/qMdZB8TH8FWWboQ and can be adapted to QGIS.

Best regards

Stefan

Am 05.02.2024 um 20:45 schrieb Steve Research via QGIS-User:
Does anyone know how to locate small features on a digital surface model (dsm) 
in qgis and get their coordinates?

I have a field surface with distributed molehills they show up in the dsm but 
is there a tool that will mark them as objects to digitise their locations?

I have Qgis + Saga etc. but don’t know if there is a process to mark these 
without having to do it by hand (I have lots of fields to do!).



Sent from my iPhone

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