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Spatial resolution & method name used for deriving DTM and DSM (Computree)
Added by Ghimire Suman over 5 years ago
Hello guys,
How can i get information relating to spatial resolution of the DTM and DSM derived from Computree. Similarly, what is the method name used to derive the DTM and DSM using Computree. I am required to put the method name and spatial resolution in the figure caption.
Thanks a lot.
Best Regards,
Suman Ghimire
Nepal
Replies (4)
RE: Spatial resolution & method name used for deriving DTM and DSM (Computree) - Added by Torresan Chiara over 5 years ago
For deriving DTM:
METHODNAME = ComputeDTM
PARAMETERS = cellsize, windowsize, smoothingneighbourhood
I can not help you with DSM, but when you set parameters or set inputs in the upper part of the window you can read the methodname.
Cheers, Chiara
RE: Spatial resolution & method name used for deriving DTM and DSM (Computree) - Added by Piboule Alexandre over 5 years ago
Hello,
The only publication containing informations about this DTM method (plugin ONF) is (but description is very short):
https://hal.archives-ouvertes.fr/hal-00646403/document
In the ONF plugin, the step are : ONF_StepClassifyGround (classification of ground points in TLS) and ONF_StepComputeDTM02 (interpolation).
ONF_StepClassifyGround works as follow:
- Compute a Zmin grid at specified resolution
- Filtering by point density in a slice of specified thickness from ZMin
- Filtering by neighborhood consistency (slope test between considered cell and neighbors cells)
ONF_StepComputeDTM02 compute a Delaunay triangulation on not filtered Zmin cells, and interpolate missing ones by a pondered mean (pondered by distance of neighbors in the triangulation). So a method close to a “natural neighbor interpolation”, using distances instead of triangles areas.
The DSM creation is just a ZMax computation by ONF_StepComputeDSMOnly step.
If you use the method provided by plugin SimpleTree, please ask to Jan Hackenberg directly.
Best regards.
Alexandre Piboule.
RE: Spatial resolution & method name used for deriving DTM and DSM (Computree) - Added by Ghimire Suman over 5 years ago
Thanks for all your reply. I also wanted to know about the spatial resolution of DTM and DSM obtained from CompuTree. How can i get spatial resolution information of my result DTM?
Looking forward to your reply
Thanks in advance
Suman
RE: Spatial resolution & method name used for deriving DTM and DSM (Computree) - Added by Piboule Alexandre over 5 years ago
Hello,
The easiest solution is to:
- Select “Item information” action,
- Show your DTM/DSM in the view,
- Select it, all informations about it (including resolution are displayed on the screen and in the log. Resolution is in meters.
Other ways are to send the DTM/DSM to a tabular view, or to export its attributes to a file (menu Export/3D Geometry/Attributes export (csv))
Best regards.
Alexandre Piboule.