Dem Earth uses EPSG:4326..


Most of the time, height data (DEM, DTM, DSM) is contained in Geotiff files. The has become the defacto standard.


The advantage of geotiff is that it is basically just tiff, with some extra tags. Tiff is supported by every tool out there.

The extra tags contain details about the referencing system, so that the data or image can be placed somewhere reliably(GeoReferenced).


In the latest versions (5.650) or greater, dem earth can now read Geotiffs directly from it's data manager. No need for a world file for referencing.


Since R6.240, DEM Earth has its own ultra fast threaded geotiff loader, which deals with bigtiffs, and rare but effective compression codecs such as Adobe deflate and Lerc.  


The data manager can open any geotiff and read its referencing header. The geotiff has to be in EPSG:: 4326. in newer DEM Earth version, you can connect DEM Earth to QGIUS, to take care of warping your geotiffs to 4326.


if the projection is not compatible(not EPSG:4326), and you have set up QGIS on your computer correctly, DEM Earth can use QGIS to reproject the image to a compatible projection for you. It will ask you if you want to do this. if you respond with "yes" it will locate QGIS, open a command line console, and run the command line tool to reproject your image. This runs in the background. when it has finished, it will update the data manager, and load in your newly reprojected geotiff.  The new geotiff has the same name as the one you selected, but has 4326_ appended to its file name.



FWIW..

  • I made this functionality for this for my own use. So that I don't have to use global mapper to do this slow task.
  • I understand that not many people will use this. 
  • If you do need it, I will gladly explain and talk you through this process in detail. For that I charge 1 hour of support to get this setup and working. it is fiddly, but once it is inplace and running it is very simple to use, and absurdly fast at reprojections. *.  This is as good and as comfortable as it gets. 
  • Get In touch if you need a walk through.


*with this setup, I am able to reproject files in seconds or minutes which global mapper takes hours or even days to process. Global mapper costs a lot of money, and reprojections are pretty much all I ever use it for. By adding this bridge, I can more or less save myself the cost of global mapper moving forward. 


  • You can of course reproject anything yourself, in QGIS, using warp.
  • you can also use global mapper and I am sure there are other tools that will do it.
  • However, there is nothing out there there that is as convenient, and fast at doing it, as DEM Earth with its QGIS link. It is crazy easy to do, once you make that QGIS connection.



Moving forward


There are many other things I could add in the same way, but first I have to see if there is any interest or demand from users, for going down this road. For example, automate the generation of massive, accurate contour splines, from geographic height data. I have already added support for .SHP file import to the Poly object. 


If there is any real interest in this connection, and expanding it to do more, get in touch.


best

Paul