[GIS] Using wildcards to work around GDAL character limit

gdalqgisrasterwildcard

I am attempting to use the 'Merge' & 'Create VRT' tools in QGIS 2.0 on
a folder with 3000+ raster tiles in.

However whenever I try to perform this operation the following error appears:

The process failed to start. Either the invoked program is missing, or
you may have insufficient permissions to invoke the program.

The process works when I select only a few tiles, so I can only assume it's due to a character restriction due to the number of files?

Upon searching the website for a solution I came across the concept of using 'Wildcards' to get around this problem:

Having problems creating VRT in QGIS from png files

However I cannot find any clear explanation on how to use them, and I don't have much experience with using OSGeo4W outside of the QGIS GUI.

Best Answer

Create an input file list using a text editor (just one input filename per line), and use -input_file_list:

gdalbuildvrt -input_file_list mylist.txt my.vrt

This allows any number of input files. You should be able to get to gdals command line tools by opening an osgeo4w shell from the start menu.

Related Solutions

[GIS] Building a virtual raster catalog

I am intrigued as to why you are using a raster version of OS AddressBase as its most useful in its vector form. Ordnance Survey supply the product in either CSV or GML formats. Same goes for CodePoint (though that one is available as CSV or NTF).

However, format aside you are still facing an issue creating a VRT data set from the TIF files. The error message would suggest one of two things:

1) You are missing the necessary executable file 2) You dont have permission to write to the location you are trying to write the output to

Taking each one separately...

Missing Executable: Check to make sure you have the gdalbuildvrt.exe file in your QGIS installation directory as I believe this is what is used to create the VRT dataset. If the file is missing then you will need to install GDAL to get it and all the dependencies.

Output Location Permissions: Check to make sure the location you are trying to create the VRT has the right permissions set.

Hope one of these suggestions helps you out. If not perhaps you could post more details such as the steps you are following which might help us to try and replicate your issue.

[GIS] QGIS GDALtools plugin problem

By the path you have shown, I'm going to assume you are using a Mac. Also assuming you have used the standard KyngChaos.com installer for GDAL.

Try this path instead:

/Library/Frameworks/GDAL.framework/Versions/1.9/Programs

The 'Versions/1.9/Programs/usr/bin' subdirectory doesn't exist, but the Versions/1.9/unix/bin does and should only contain the gdal-config tool (not used by GDALTools plugin). The binaries used by the GDALTools plugin should all be located in the Programs directory listed above.

Test by running the Raster->Miscellaneous->Information tool on a raster layer.

Best Answer

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[GIS] Building a virtual raster catalog

[GIS] QGIS GDALtools plugin problem

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