I publish an article at only-original-content.com. The article has some images that are served from only-original-content.com/images. Now only-copied-content.com takes my original article and republishes it. Since only-copied-content simply copied the HTML, the images are still served from only-original-content.com/images.

In that case it should be simple to determine who is the original publisher. Of course, only-original-content.com could simply be a CDN that only-copied-content.com uses for its static resources, but, again, it should be easy to determine whether that is the case.