SURE Editor: How to improve DSMs & TrueOrthos
Step 1: Create a DSM Mesh
Since the release of Version 2.2.1 untextured DSM Meshes can be created as part of the regular SURE Aerial and SURE Professional licenses.
Step 2: Edit the DSM Mesh using the SURE Editor
SURE Meshes in the osgb format can be edited using the SURE Editor. For more details on editing please consult the documentation of the SURE Editor (Edit Mode).
As soon as editing is done, please use the "Save" or "Save as" feature of the Editor to save the edited mesh.
Additionally the Editor offers an option to export a list of all mesh tiles that have been edited via the editing menu.
This is especially useful if users only wish to generate DSMs for the mesh tiles that were edited, rather than the whole project.
Even if no additional editing is done the DSMs derived from the DSM Mesh will produce slightly different results than the DSMs produced from the Dense Cloud. Typical effects are fewer data gaps due to interpolation in the DSM Mesh step and sharper jumps along edges due to DSM Mesh post-processing.
Step 3: Derive a DSM from the edited Mesh
The 2.5D Tool and ModuleDsm.exe support meshes as an input. In order to derive a DSM from the edited mesh all that has to be done is to use a list of edited mesh tiles, similar to the dsmmeshlist.txt.
This list can be passed using the 2.5D Tool or using the --cloud parameter of the ModuleDsm.exe. For more information also refer to the documentation of ModuleDsm.exe.
All mesh tiles that are present in the list will be processed. An easy way to generate a list containing only edited mesh tiles is described in Step 2 above.
When deriving DSMs from a Mesh it is recommended to turn off Speckle Filtering during the DSM process and set the Minimum detections per cell (also referred to as "Manifold") to 1. This can be achieved via the controlDsm.txt and the GUI respectively.
This recommendation only applies when deriving DSMs from DSM Meshes and not in general, since the DSM Mesh already went through several filtering steps upon its creation.
Using the main linking file (usually called "main.osgb") is currently not supported. Please use a list of paths referring to mesh tiles (usually called "Main_DSM_XXXXX_XXXXX.osgb"). An example of such a list is the dsmmeshlist.txt that is generated as part of the DSM Mesh process.