How do I exclude some items from an Open Source software project (such as resource images) even though they are required by the project?

Question

I am just about to release a few software projects under the Apache Open Source License 2.0.

While creating the projects I have purchased the legal rights to royalty-free images which I use in the project. A specific example is the image I use as an icon.

However, the original license doesn't allow others to use those images (for derivative products) as they like, since the future users haven't paid the royalty.

Am I allowed to include the royalty-free images along with the Open Source project on GitHub (for example)?

Is there a proper way to indicate that certain resources (images, sound files, etc) are not included in the Open Source code itself?

I know many of these answers may require exact detailed information. I'm just attempting to get a general idea.

Answer 1

Am I allowed to include the royalty-free images along with the Open Source project on GitHub (for example)?

This depends on the exact details of the license under which you can use the images and in particular if the license terms are automatically transferred to someone who obtains a copy of the image.
If the license is not transferable, then you should not put the images in a publicly accessible repository.

---

If you put the images in a publicly accessible repository, then you should also put a text file in there with the license of the images and you should make it clear in the documentation that the code and the images live under different licenses.

For example, you could place two LICENSE files in the root folder of your repository:

• LICENSE.md

  This license applies only to the code in this repository. 
  Images and other assets are explicitly excluded.
  
  <license text for your code license...>
  

• LICENSE-images.md

  This license applies only to the images in this repository. 
  
  <license text for your image files...>
  

Answer 2

If I can download those images because you put them somewhere where I can download them, then you committed copyright infringement. So don't do this.

You could replace these images with some hand-drawn images, make a list of those images, and some documentation where I can get the good quality images and how to get a license.

Or you could hire someone to create images that you can use freely.