There was a question like this, but it was about JPG pictures. I have the same one about PNG pictures.
I've recently had trouble where someone stole an artwork of mine and put it as a YouTube avatar. My mistake was that I didn't watermark it in any way. Now, I think that watermarks can be erased by using the Posterize effect in painting programs.
I'm wondering if it's possible to insert hidden information about my copyright into my PNG pictures in a way that people can't see it, but that an admin can use a program for scanning DRM to see the proof that the artwork is mine.
The DRM must NOT prevent the pictures from being seen on browsers, downloaded to devices, copied or renamed on their storage devices, shared/reposted(with permission)/linked on other websites. The DRM must NOT have any adware/malware/spyware on my pictures. The DRM must work regardless of how people stretch, crop or convert my picture. The pictures must just be trackable by the DRM information so that whoever uses my artwork can be caught.
Does anyone know for any DRM inserting and scanning programs for PNG pictures?