This package is meant for use in combination with the material (in particular the source code) hosted at github:

https://github.com/Spataner/trafficsign-cyclegan

Follow the instructions there.

It contains a number of traffic sign icon images that are used to generate life-like traffic signs. They are taken from

https://commons.wikimedia.org/wiki/Road_signs_of_Germany 

and are public domain. The file format has been changed to Portable Network Graphics (PNG).