IDF is the data format used by Austrian authorities to publish the official open government street graph. It’s basically a text file describing network nodes, links, and permissions for different modes of transport.
Since, to my knowledge, there hasn’t been any open source IDF parser available so far, I’ve started to write my own using PyQGIS. You can find the script which is meant to be run in the QGIS Python console in my Github QGIS-resources repo.
I haven’t implemented all details yet but it successfully parses nodes and links from the two example IDF files that have been published so far as can be seen in the following screenshot which shows the Klagenfurt example data:
If you are interested in advancing this project, just get in touch here or on Github.