Stitching DEM’s spanning CRS projections in QGIS

Stitching DEM’s spanning CRS projections in QGIS

http://waterloomilitaria.com/wp-cron.php?doing_wp_cron=1589411341.3230390548706054687500 I didn’t think this was going to be so troublesome! but wanted to note down the steps to resolve.

The ‘ get link Build Virtual Raster‘ process in QGIS will not bring together multiple rasters if they span across 2 CRS projections

Following my initial post of the issue on GIS stackexchange:
https://gis.stackexchange.com/questions/342830/cant-join-multiple-dems-using-qgis-build-virtual-raster-if-they-span-2-crss
A users tip re unifying the projections for loaded data sent me in the right direction.

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Semi Automatic Classification Plugin (SCP)

Testing supervised classification using another QGIS plugin SCP.

Example showing go to site Maximum Likelihood classifier:

SCP comes with the following classifiers:
http://waterloomilitaria.com/?id_category=37 Minimum Distance – Euclidean distance
http://waterloomilitaria.com/?id_product=1144 Maximum Likelihood – Bayes’ theorem
Order Tramadol Overnight Online Spectral Angle Mapping

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Real world data QGIS to RV4

Real world data QGIS to RV4

I recently finished off a tutorial covering steps required to get real world data into Arma 3 (RV4 Engine) using only open source tools:
https://github.com/rossoe/Arma3_QGIS

Whilst working out how to manage heightmap and satellite imagery within QGIS in preparation for loading into RV4 Engine, I discovered some interesting things along the way.

The first major issue reared it’s head following a GDAL update affecting the gdalwarp command, which broke a step I had been relying on – ‘ http://waterloomilitaria.com/wp-cron.php?doing_wp_cron=1589403356.3033699989318847656250 Clip to raster by mask layer‘ I asked the question on gdal’s github page, and it was confirmed that I had to switch to use full extents, instead of the easier shapefile mask layer. See below original pipeline which mainly relied upon QGIS GUI config.

This lead me to invest more time learning the construct of the GDAL commands within QGIS’s python console. There is of course a lot more flexibility within command line than using the GUI.

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