How to creae DEM from Worldview 2 imagery

[Intellgis]

Hi frnds,

I have Worldview-2 Orthorectified Multispectral 8 band imagery.

IS it possible to create a DEM from this imagery ? What are the steps and what is the advised software.

Regards,

Intellgis

[hariasa]

You can create a DSM (Digital Surface Model) using stereo WorldView-2 Images in programs such as LPS (in ERDAS). The procedure is quite easy (place a handful of ground control points, GCP's distributed over the image, where you rectify it with either manually measured points or an pre-existing DTM and Ortho image), however it takes some manual labour and it could take long if you have many images/big area. Afterwards you can attempt to create a DTM (Digital Terrain Model) using the eATA software which then filters out points depending on their classification. There are many options involved in eATA which you can all find in the very useful helpfile. In my experience however it needs a lot of manual correcting (AND processing power!).

... I think you can also use point cloud classifiers/filter algorithms to generate a DTM and Normalized Heights... but I am too busy to experiment with that.

Usually you create a DSM from these images in order to produce Ortho's (the stuff you have) unless there is a better one available. Hence you can't really create a DEM from Ortho's since they are already corrected.