I'm looking into a couple I found online. Digimarc looks good but I've got some time to think about the others​.
Just as a point of reference, I tried Digimarc for one year and it didn't find a single instance of one of my images being used elsewhere even though a simple reverse image search showed numerous examples of a number of my images being used without my permission. Unless they have changed their plans, Digimarc does not search photo sharing sites like flickr, 500px, etc or social media sites like Facebook.




