Getting black square after merging two rasters in QGIS
Tested on a clean install of the QGIS Standalone Installer Version 3.4, on a 64-bit Windows 10 machine.
QGIS 3.4.3 seems to install a version of the numpy module that is not what gdal_merge needs.
After several attempts, I found this solution:
Run as Administrator the OSGeo4W.bat file, located at the QGIS 3.4 folder (C:\Program Files\QGIS 3.4 by default), that calls enviroment variables and opens a shell with administrator privileges
run:
python -m pip show numpy
, returnsVersion: 1.12.1+mkl
run:
python -m pip uninstall numpy
, agree to proceed, returnsSuccessfully uninstalled numpy-1.12.1+mkl
run:
python -m pip install numpy
, returnsSuccesfully installed numpy-1.15.4
close the shell and run the Merge function in QGIS again, it will work fine now.