[nolok]

> There are other more sophisticated methods which I can't mention here

I found that very funny in a austin power kind of way, like this is some sort of giant secret technology.

The most efficient methods of watermarking pictures in ways that are easy to detect, easy to hide for the viewer yet hard to remove for the copier are all well known and detailed on the internet, in fact wikipedia is a decent source before going into more technical content.

And in terms of "memes", this sort of watermark is most often done by individual users for reasons related to ego rather that copyright protection. Because the actual money making memes oriented websites will prefer the good old heavy duty watermark all over the picture, since it will be copied anyway they figure they might as well ensure the final viewer knows where it came from so he can look for it and get them new traffic.